R/Class-IrisClient.R

In IRISSeismic: Classes and Methods for Seismic Data Analysis

##
##    S4 classes for communicating with IRIS DMC web services.
##
##    Copyright (C) 2012  Mazama Science, Inc.
##    by Jonathan Callahan, jonathan@mazamascience.com
##
##    This program is free software; you can redistribute it and/or modify
##    it under the terms of the GNU General Public License as published by
##    the Free Software Foundation; either version 2 of the License, or
##    (at your option) any later version.
##
##    This program is distributed in the hope that it will be useful,
##    but WITHOUT ANY WARRANTY; without even the implied warranty of
##    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
##    GNU General Public License for more details.
##
##    You should have received a copy of the GNU General Public License
##    along with this program; if not, write to the Free Software
##    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

################################################################################
# R classes for an IRIS web services request client.
#
# Inspiration for the functionality in this code comes from obspy.iris.client.Client 
# 
#   http://docs.obspy.org/packages/autogen/obspy.iris.client.Client.html
#
#
# Documentation for FDSN Web Services is available here:
#
#   http://www.fdsn.org/webservices/
#
################################################################################

################################################################################
# Class IrisClient
#
# IRIS Web service request client.
#
# Documentation verbatim from obspy.iris.client.Client:
#
#    :type site: str, optional
#    :param site: Base URL of the IRIS Web service (default
#        is ``'http://service.iris.edu/'``).
#    :type service_type: str, optional
#    :param service_type: second element of URL, usually fdsnws
#    :type debug: bool, optional
#    :param debug: Enables verbose output (default is ``False``).
#    :type user_agent: str, optional
#    :param user_agent: Sets an client identification string which may be
#        used on server side for statistical analysis (default contains the
#        current module version and basic information about the used
#        operation system, e.g.
#        ``'ObsPy 0.4.7.dev-r2432 (Windows-7-6.1.7601-SP1, Python 2.7.1)'``.
#
################################################################################


# check for a user R profile for the IRIS Client site URL
# otherwise, use the default URL
irisSite <- "http://service.iris.edu"
if (Sys.getenv("IrisClient_site") != "") {
	irisSite <- Sys.getenv("IrisClient_site")
}
# check R profile for specific reference to .netrc authentication file
# which allows us to access restricted data sets
# e.g. irisNetrc <- "/home/mustang/mustang.netrc"
# we will use no default here
irisNetrc <- NULL
if (Sys.getenv("IrisClient_netrc") != "") { 
	irisNetrc <- Sys.getenv("IrisClient_netrc")
}

# we will want the client using us as a library to be able to identify itself.
# it's easy enough to make this an environment setting as well.
# we will generate a default user agent to represent the metrics calculators.
irisUserAgent <- "unidentified R script"
if (Sys.getenv("IrisClient_agent") != "") {
	irisUserAgent <- Sys.getenv("IrisClient_agent")
}

useragent1 = paste0("IRISSeismic/",
                    ifelse("IRISSeismic" %in% rownames(installed.packages()),
                           installed.packages()["IRISSeismic","Version"], "local code"),
                    " RCurl/",
                     ifelse("RCurl" %in% rownames(installed.packages()),
                           installed.packages()["RCurl","Version"], "local code"),
                    " R/", R.version$major,".",R.version$minor,
                    " ", version$platform,
                     " (",irisUserAgent,")")


setClass("IrisClient", 
         # typed slots (aka attributes) for class IrisClient
         representation(site = "character",
                        service_type = "character",
                        debug = "logical",
                        useragent = "character")
)

setMethod("initialize","IrisClient",
          function(.Object, site=irisSite,debug=FALSE, useragent=useragent1, service_type="fdsnws"){
              .Object@site=site
              .Object@service_type=service_type
              .Object@debug=debug
              .Object@useragent=useragent
              .Object
          })


################################################################################
# getDataselect method returns a Stream object
#
# This implementation matches some of the functionality in the obspy dataselect
# function.
# 
#   http://docs.obspy.org/_modules/obspy/iris/client.html#Client.dataselect
#
################################################################################

if (!isGeneric("getDataselect")) {
  setGeneric("getDataselect", function(obj, network, station, location, channel, starttime, endtime, ...) {
    standardGeneric("getDataselect")
  })
}

getDataselect.IrisClient <- function(obj, network, station, location, channel, starttime, endtime, quality=NULL,
                                     repository=NULL, inclusiveEnd=TRUE, ignoreEpoch=FALSE) {

  if (!is.logical(inclusiveEnd)) {
     stop(paste("getDataselect.IrisClient: option inclusiveEnd must be TRUE or FALSE"))
  }
  if (!is.logical(ignoreEpoch)) {
     stop(paste("getDataselect.IrisClient: option inclusiveEnd must be TRUE or FALSE"))
  }
  # allow authenticated access.
  # if we have a netrc definition, then use queryauth to access data
  # else, use standard query call
  url <- NULL
  
  #print(paste0("irisNetrc=",irisNetrc))

  if (! is.null(irisNetrc)) {
    	url <- paste(obj@site,obj@service_type,"dataselect/1/queryauth?",sep="/")
  } else {
    	url <- paste(obj@site,obj@service_type,"dataselect/1/query?",sep="/")
  }
  if (obj@service_type == "ph5ws") {
     url <- paste(url,"reqtype=fdsn&net=", network,sep="")
  } else {
     url <- paste(url,"net=", network,sep="")
  }
  url <- paste(url,"&sta=", station,sep="")
  # NOTE:  Locations with blanks must be converted into "--" when creating the URL
  # NOTE:  For getDataselect only, convert "" to "--"
  location <- ifelse(location=="","--",location)
  url <- paste(url,"&loc=", stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=", channel,sep="")
  url <- paste(url,"&start=", format(starttime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  if (! inclusiveEnd) {
      endtime <- endtime-0.000001
      url <- paste(url,"&end=", format(endtime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  } else {
      url <- paste(url,"&end=", format(endtime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  }
  url <- paste(url,"&nodata=204",sep="")
  if (!is.null(quality) && obj@service_type != "ph5ws" ){
    url <- paste(url,"&quality=",quality,sep="")
  }
  if (!is.null(repository) && obj@service_type != "ph5ws"){
    if (repository %in% c("realtime","primary","bud","primary,realtime","realtime,primary")){
      url <- paste(url,"&repository=",repository,sep="")
    } else {
      err_msg <- c("Invalid repository, acceptable values are 'realtime' and 'primary'. To search both, do not specify a repository.")
      stop(paste("getDataselect.IrisClient:",err_msg))   
    }
  }

  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Make authenticated request using a netrc file
  if (! is.null(irisNetrc)) {
        h <-  RCurl::basicTextGatherer()
        result <- try( dataselectResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent, 
				             netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)), 
                       silent=TRUE)

        # Handle error response
        if (inherits(result,"try-error")) {
	    err_msg <- geterrmessage()
            stop(paste("getDataselect.IrisClient:",err_msg, url))
	}

        result <- try(header <- RCurl::parseHTTPHeader(h$value()))
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getDataselect.IrisClient:",err_msg, url))
        }

        if (header["status"] == "401") {  # authentication error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( dataselectResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)), 
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getDataselect.IrisClient:",err_msg, url))
            }

            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getDataselect.IrisClient:",err_msg, url))
            }
        }
        if (header["status"] == "500") {  # internal server error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( dataselectResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getDataselect.IrisClient:",err_msg, url))
            }
            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getDataselect.IrisClient:",err_msg, url))
            }
        }

  } else {
        h <-  RCurl::basicTextGatherer()
  	result <- try( dataselectResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                       silent=TRUE)

        # Handle error response
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getDataselect.IrisClient:",err_msg,url))
        }

        result <- try(header <- RCurl::parseHTTPHeader(h$value()))
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getDataselect.IrisClient:",err_msg, url))
        }

        if (header["status"] == "500") {  # internal server error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( dataselectResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getDataselect.IrisClient:",err_msg, url))
            }
            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getDataselect.IrisClient:",err_msg, url))
            }
        }

  }


  if (header["status"] == "204") {  #fdsnws dataselect returned nothing
      stop(paste("getDataselect.IrisClient: No Data:",header["status"],url))
  }

  if (header["status"] != "200") {  #fdsnws dataselect returned something unexpected
      if (header["status"] == "400") {
           stop(paste("getDataselect.IrisClient: Bad Request:",url))
      } else if (header["status"] == "404") {
           stop(paste("getDataselect.IrisClient: URL Not Found:",url))
      } else {
           stop(paste("getDataselect.IrisClient: Unexpected http status code",header["status"],header["statusMessage"],url))
      }
  }

  # No errors so proceed
  
  # Channel metadata is required to properly apply InstrumentSensitivity corrections
  result <- try( channels <- getChannel(obj, network, station, location, channel, starttime, endtime),
                 silent=TRUE)
  
  # Handle error response
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getDataselect.IrisClient:",err_msg, url))
  }  
  
  # NOTE:  Sometimes, the station webservice will return multiple records for the same SNCL
  # NOTE:  each with a different scale or starttime.  This still represents a single SNCL.
  # NOTE:  What to do about multiple scales in the following getChannel request?
  # Solution 1: if ignoreEpoch==TRUE, then just take the first epoch presented
  # http://service.iris.edu/fdsnws/station/1/query?net=H2&sta=H2O&loc=00&cha=LHZ&starttime=2001-02-28T18:29:44&endtime=2001-02-28T19:29:44&includerestricted=false&format=text&level=channel

  sncls <- paste(channels$network,channels$station,channels$location,channels$channel)
  if (nrow(channels) > 1 && !ignoreEpoch) {
    stop(paste("getDataselect.IrisClient: Multiple epochs: getChannel returned",length(sncls),"records"))
  } else {
    channelInfo <- channels[1,]
  }
  
  # No errors so proceed

  stream <- miniseed2Stream(dataselectResponse,url,starttime,endtime,
                            channelInfo$instrument,channelInfo$scale,channelInfo$scalefreq,channelInfo$scaleunits,channelInfo$latitude,
                            channelInfo$longitude,channelInfo$elevation,channelInfo$depth,channelInfo$azimuth,channelInfo$dip)
  
  return(stream)
}

# All arguments specified
setMethod("getDataselect", signature(obj="IrisClient", network="character", station="character", location="character",
                                     channel="character", starttime="POSIXct", endtime="POSIXct"),
          function(obj, network, station, location, channel, starttime, endtime, ...)
            getDataselect.IrisClient(obj, network, station, location, channel, starttime, endtime, ...))

################################################################################
# getSNCL method is a convenience wrapper for getDataselect
################################################################################

if (!isGeneric("getSNCL")) {
  setGeneric("getSNCL", function(obj, sncl, starttime, endtime, ...) {
    standardGeneric("getSNCL")
  })
}

getSNCL.IrisClient <- function(obj, sncl, starttime, endtime, quality=NULL, repository=NULL, inclusiveEnd=TRUE, ignoreEpoch=FALSE) {
  parts <- unlist(stringr::str_split(sncl,'\\.'))
  return( getDataselect.IrisClient(obj, parts[1], parts[2], parts[3], parts[4], starttime, endtime, 
                                   quality=quality, repository=repository, inclusiveEnd=inclusiveEnd, ignoreEpoch=ignoreEpoch) )
}

# All arguments specified
setMethod("getSNCL", signature(obj="IrisClient", sncl="character", starttime="POSIXct", endtime="POSIXct"),
          function(obj, sncl, starttime, endtime, ...)
            getSNCL.IrisClient(obj, sncl, starttime, endtime, ...))

################################################################################
# getTimeseries method returns a Stream object
#
# Data are obtained from the timeseries web service:
# 
#   http://service.iris.edu/irisws/timeseries/1/
#
# This method functions much like getDataselect() but allows for various types
# of signal processing.
#
################################################################################

if (!isGeneric("getTimeseries")) {
  setGeneric("getTimeseries", function(obj, network, station, location, channel, starttime, endtime, ...) {
    standardGeneric("getTimeseries")
  })
}

getTimeseries.IrisClient <- function(obj, network, station, location, channel, starttime, endtime, processing=NULL, 
                                                            repository=NULL,inclusiveEnd=TRUE, ignoreEpoch=FALSE) {
  if (!is.logical(inclusiveEnd)) {
     stop(paste("getTimeseries.IrisClient: option inclusiveEnd must be TRUE or FALSE"))
  }
  if (!is.logical(ignoreEpoch)) {
     stop(paste("getTimeseries.IrisClient: option inclusiveEnd must be TRUE or FALSE"))
  }

  url <- NULL
  if (! is.null(irisNetrc)) {
        url <- paste(obj@site,"irisws/timeseries/1/queryauth?",sep="/")
  } else {
        url <- paste(obj@site,"irisws/timeseries/1/query?",sep="/")
  }
 
  url <- paste(url,"net=", network,sep="")

  url <- paste(url,"&sta=", station,sep="")
  # NOTE:  Locations with blanks must be converted into "--" when creating the URL
  # NOTE:  For getTimeseries only, convert "" to "--"
  location <- ifelse(location=="","--",location)
  url <- paste(url,"&loc=", str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=", channel,sep="")
  url <- paste(url,"&start=", format(starttime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  if (! inclusiveEnd) {
      endtime <- endtime-0.000001
      url <- paste(url,"&end=", format(endtime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  } else {
      url <- paste(url,"&end=", format(endtime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  }
  if (!is.null(repository) && obj@service_type != "ph5ws"){
    if (repository %in% c("realtime","primary","bud","primary,realtime","realtime,primary")){
      url <- paste(url,"&repository=",repository,sep="")
    } else {
      err_msg <- c("Invalid repository, acceptable values are 'realtime' and 'primary'. To search both, do not specify a repository.")
      stop(paste("getTimeseries.IrisClient:",err_msg))
    }
  }
  
  if (!is.null(processing)) {
    url <- paste(url,processing,sep="")
  }
  
  url <- paste(url,"&format=miniseed",sep="")
  
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Make webservice request
   # Make authenticated request using a netrc file
  if (! is.null(irisNetrc)) {
        h <-  RCurl::basicTextGatherer()
        result <- try( timeseriesResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                             netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                       silent=TRUE)

        # Handle error response
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getTimeseries.IrisClient:",err_msg, url))
        }

        result <- try(header <- RCurl::parseHTTPHeader(h$value()))
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getTimeseries.IrisClient:",err_msg, url))
        }
        if (header["status"] == "401") {  # authentication error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( timeseriesResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }

            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }
        }
        if (header["status"] == "500") {  # internal server error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( timeseriesResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }
            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }
        }

  } else {
        h <-  RCurl::basicTextGatherer()
        result <- try( timeseriesResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                       silent=TRUE)

        # Handle error response
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getTimeseries.IrisClient:",err_msg,url))
        }

        result <- try(header <- RCurl::parseHTTPHeader(h$value()))
        if (inherits(result,"try-error")) {
            err_msg <- geterrmessage()
            stop(paste("getTimeseries.IrisClient:",err_msg, url))
        }

        if (header["status"] == "500") {  # internal server error, try again
            Sys.sleep(3)
            h <-  RCurl::basicTextGatherer()
            result <- try( timeseriesResponse <- RCurl::getBinaryURL(url, useragent=obj@useragent,
                                                 netrc=1, netrc.file=irisNetrc, .opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                           silent=TRUE)
            # Handle error response
            if (inherits(result,"try-error")) {
               err_msg <- geterrmessage()
               stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }
            result <- try(header <- RCurl::parseHTTPHeader(h$value()))
            if (inherits(result,"try-error")) {
              err_msg <- geterrmessage()
              stop(paste("getTimeseries.IrisClient:",err_msg, url))
            }
        }

  }


  if (header["status"] == "204") {  #irisws timeseries returned nothing
      stop(paste("getTimeseries.IrisClient: No Data:",header["status"],url))
  }

  if (header["status"] != "200") {  #irisws timeseries returned something unexpected
      if (header["status"] == "400") {
           stop(paste("getTimeseries.IrisClient: Bad Request:",url))
      } else if (header["status"] == "404") {
           stop(paste("getTimeseries.IrisClient: URL Not Found:",url))
      } else {
           stop(paste("getTimeseriesIrisClient: Unexpected http status code",header["status"],header["statusMessage"],url))
      }
  }


  # No errors so proceed

  # Channel metadata is required to properly apply InstrumentSensitivity corrections
  result <- try( channels <- getChannel(obj, network, station, location, channel, starttime, endtime),
                 silent=TRUE)

  # Handle error response
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getTimeseries.IrisClient:",err_msg, url))
  }
  
  # NOTE:  Sometimes, the station webservice will return multiple records for the same SNCL
  # NOTE:  each with a different scale or starttime.  This still represents a single SNCL.
  # NOTE:  What to do about multiple scales in the following getChannel request?
  # Solution 1: if ignoreEpoch==TRUE, then just take the first epoch presented
  # http://service.iris.edu/fdsnws/station/1/query?net=H2&sta=H2O&loc=00&cha=LHZ&starttime=2001-02-28T18:29:44&endtime=2001-02-28T19:29:44&includerestricted=false&format=text&level=channel

  sncls <- paste(channels$network,channels$station,channels$location,channels$channel)
  if (nrow(channels) > 1 && !ignoreEpoch) {
    stop(paste("getTimeseries.IrisClient: Multiple epochs: getChannel returned",length(sncls),"records"))
  } else {
    channelInfo <- channels[1,]
  }

  # No errors so proceed

  stream <- miniseed2Stream(timeseriesResponse,url,starttime,endtime,
                            channelInfo$instrument,channelInfo$scale,channelInfo$scalefreq,channelInfo$scaleunits,channelInfo$latitude,
                            channelInfo$longitude,channelInfo$elevation,channelInfo$depth,channelInfo$azimuth,channelInfo$dip)

  return(stream)
}

# All arguments specified
setMethod("getTimeseries", signature(obj="IrisClient", network="character", station="character", location="character",
                                     channel="character", starttime="POSIXct", endtime="POSIXct"),
          function(obj, network, station, location, channel, starttime, endtime, ...)
            getTimeseries.IrisClient(obj, network, station, location, channel, starttime, endtime, ...))



################################################################################
# getRotation method returns a list of three Stream objects
#
# Data are obtained from the rotation web service:
# 
#   http://service.iris.edu/irisws/rotation/1/
#
################################################################################

if (!isGeneric("getRotation")) {
  setGeneric("getRotation", function(obj, network, station, location, channelSet, starttime, endtime, processing) {
    standardGeneric("getRotation")
  })
}

getRotation.IrisClient <- function(obj, network, station, location, channelSet, starttime, endtime, processing) {
  
  url <- paste(obj@site,"/irisws/rotation/1/query?",sep="")
  url <- paste(url,"net=", network,sep="")
  url <- paste(url,"&sta=", station,sep="")
  # NOTE:  Locations with blanks must be converted into "--" when creating the URL
  # NOTE:  For getRotation only, convert "" to "--"
  location <- ifelse(location=="","--",location)
  url <- paste(url,"&loc=", stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&chaset=", channelSet,sep="")
  url <- paste(url,"&start=", format(starttime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&end=", format(endtime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  
  url <- paste(url,processing,sep="")    
  
  url <- paste(url,"&output=miniseed",sep="")
  
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Download the rotation service response (zip file) to a temporary file
  temp <- tempfile()
  utils::download.file(url,temp,quiet=TRUE)
  
  # Create a dataframe of zip file contents and discard the metadata file
  zipContents <- utils::unzip(temp,list=TRUE,junkpaths=TRUE)
  metadata_mask <- stringr::str_detect(zipContents$Name,"metadata")
  zipContents <- zipContents[!metadata_mask,]
  
  # Sanity check
  if (nrow(zipContents) != 3) {
    stop(paste("IrisClient.getRotation: rotation service return has",nrow(zipContents),"traces -- 3 expected"))
  }
  
  # Extract the three miniseed records, convert them to Stream objects and store them in streamList
  streamList <- list()
  for (i in seq(3)) {
    con <- unz(temp,zipContents$Name[i],open="rb")
    rawMiniseed <- readBin(con,"raw",zipContents$Length[i])
    
    streamList[[i]] <- miniseed2Stream(rawMiniseed,
                                       url=paste("rotation:",zipContents$Name[i]),
                                       requestedStarttime=starttime,
                                       requestedEndtime=endtime,
                                       sensor="rotation web service")
    #                                      scale=as.integer(NA),
    #                                      scaleunits="") {    
    close(con)
  }
  
  # Remove the temporary file
  unlink(temp)
  
  return(streamList)    
}

# All arguments specified
setMethod("getRotation", signature(obj="IrisClient", 
                                     network="character", station="character", location="character",
                                     channelSet="character", starttime="POSIXct", endtime="POSIXct",
                                     processing="character"), 
          function(obj, network, station, location, channelSet, starttime, endtime, processing) 
            getRotation.IrisClient(obj, network, station, location, channelSet, starttime, endtime, processing))


################################################################################
# getNetwork method returns a dataframe with information from the output
# of the fdsn station web service with "format=text&level=network".
#
#   http://service.iris.edu/fdsnws/station/1/
#
# Example output:
#
# #Network | Description | StartTime | EndTime | TotalStations
# IU|Global Seismograph Network (GSN - IRIS/USGS)|1988-01-01T00:00:00|2500-12-12T23:59:59|254
#
################################################################################

if (!isGeneric("getNetwork")) {
  setGeneric("getNetwork", function(obj, network, station, location, channel,
                                         starttime, endtime, includerestricted,
                                         latitude, longitude, minradius, maxradius) {
    standardGeneric("getNetwork")
  })
}

getNetwork.IrisClient <- function(obj, network, station, location, channel,
                                       starttime, endtime, includerestricted,
                                       latitude, longitude, minradius, maxradius) {
  
  # Parameters common to all 'station' webservice requests
  url <- paste(obj@site,obj@service_type,"station/1/query?",sep="/")
  url <- paste(url,"net=",ifelse(network=="","*",network),sep="")
  url <- paste(url,"&sta=",ifelse(station=="","*",station),sep="")
  # NOTE:  Blank locations containing two spaces must be converted to "--"
  location <- ifelse(location=="","*",location)
  url <- paste(url,"&loc=",stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",ifelse(channel=="","*",channel),sep="")
  url <- paste(url,"&starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&nodata=204",sep="")
  if (obj@service_type != "ph5ws") {
    url <- paste(url,"&includerestricted=",ifelse(includerestricted,"true","false"),sep="")
  }
  url <- paste(url,"&format=text",sep="")
  
  # Add optional geographic constraints if they are passed in
  if (!missing(latitude)) {
    url <- paste(url,"&latitude=",latitude,sep="")      
  }
  if (!missing(longitude)) {
    url <- paste(url,"&longitude=",longitude,sep="")      
  }
  if (!missing(minradius)) {
    url <- paste(url,"&minradius=",minradius,sep="")      
  }
  if (!missing(maxradius)) {
    url <- paste(url,"&maxradius=",maxradius,sep="")      
  }
  
  # Parameters specific to the getNetwork() method
  url <- paste(url,"&level=network",sep="")
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Set up the colnames we wish to have in our dataframe
  # #Network | Description | StartTime | EndTime | TotalStations
  colNames <- c("network","description","starttime","endtime","totalstations")
  colClasses <- c(rep("character",4),"numeric")
  
  # Make webservice request
  # NOTE:  Be sure to set na.strings="" as "NA" is a valid network name  

  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)

  if (inherits(result,"try-error")) { 
     err_msg <- geterrmessage()
     stop(paste("getNetwork.IrisClient:",err_msg,url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     stop(paste("getNetwork.IrisClient:",err_msg, url))
  }


  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
      stop(paste("getNetwork.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("couldn't connect to host",ignore_case=TRUE))) {
      stop(paste("getNetwork.IrisClient: Couldn't connect to host", url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getNetwork.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getNetwork.IrisClient: Unexpected http status code",header["status"],strtrim(err_msg,500),url))
    }
  }
  if(length(gurlc) == 0) { gurlc <- "" }

  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon),add=TRUE)
  result <- try( DF <- utils::read.delim(txtcon,sep="|",col.names=colNames,colClasses=colClasses,na.strings=""),silent=TRUE)

  if (inherits(result,"try-error")) {    
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getNetwork.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getNetwork.IrisClient:",err_msg, url))
    }
  }
  
  # No errors so proceed
  
  # Convert time strings
  DF$starttime <- as.POSIXct(DF$starttime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  DF$endtime <- as.POSIXct(DF$endtime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Return a dataframe with rows ordered by network
  return(DF[order(DF$network),])
}

# All arguments specified
setMethod("getNetwork", signature(obj="IrisClient", 
                                       network="character", station="character", location="character",
                                       channel="character", starttime="POSIXct", endtime="POSIXct",
                                       includerestricted="logical",
                                       latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getNetwork.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  includerestricted, latitude, longitude, minradius, maxradius))

# includerestricted="missing", use FALSE
setMethod("getNetwork", signature(obj="IrisClient", 
                                       network="character", station="character", location="character",
                                       channel="character", starttime="POSIXct", endtime="POSIXct",
                                       includerestricted="missing",
                                       latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getNetwork.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  FALSE, latitude, longitude, minradius, maxradius))


################################################################################
# getStation method returns a dataframe with information from the output
# of the fdsn station web service with "format=text&level=station".
#
#   http://service.iris.edu/fdsnws/station/1/
#
# Example output:
#
# #Network | Station | Latitude | Longitude | Elevation | SiteName | StartTime | EndTime 
# IU|COR|44.5855|-123.3046|110.0|Corvallis, Oregon, USA|2009-09-26T00:00:00|2599-12-31T23:59:59
#
################################################################################

if (!isGeneric("getStation")) {
  setGeneric("getStation", function(obj, network, station, location, channel,
                                    starttime, endtime, includerestricted,
                                    latitude, longitude, minradius, maxradius) {
    standardGeneric("getStation")
  })
}

getStation.IrisClient <- function(obj, network, station, location, channel,
                                  starttime, endtime, includerestricted,
                                  latitude, longitude, minradius, maxradius) {
  
  # Parameters common to all 'station' webservice requests
  url <- paste(obj@site,obj@service_type,"station/1/query?",sep="/")
  url <- paste(url,"net=",ifelse(network=="","*",network),sep="")
  url <- paste(url,"&sta=",ifelse(station=="","*",station),sep="")
  # NOTE:  Blank locations containing two spaces must be converted to "--"
  location <- ifelse(location=="","*",location)
  url <- paste(url,"&loc=",stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",ifelse(channel=="","*",channel),sep="")
  url <- paste(url,"&starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&nodata=204",sep="")
  if(!is.null(includerestricted) && obj@service_type != "ph5ws") {
    url <- paste(url,"&includerestricted=",includerestricted,sep="")
  }
  url <- paste(url,"&format=text",sep="")
  
  # Add optional geographic constraints if they are passed in
  if (!missing(latitude)) {
    url <- paste(url,"&latitude=",latitude,sep="")      
  }
  if (!missing(longitude)) {
    url <- paste(url,"&longitude=",longitude,sep="")      
  }
  if (!missing(minradius)) {
    url <- paste(url,"&minradius=",minradius,sep="")      
  }
  if (!missing(maxradius)) {
    url <- paste(url,"&maxradius=",maxradius,sep="")      
  }
  
  # Parameters specific to the getStation() method
  url <- paste(url,"&level=station",sep="")
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Set up the colnames we wish to have in our dataframe
  # Network | Station | Latitude | Longitude | Elevation | SiteName | StartTime | EndTime 
  colNames <- c("network","station","latitude","longitude","elevation","sitename","starttime","endtime")
  colClasses <- c(rep("character",2),rep("numeric",3),rep("character",3))
  
  # Make webservice request
  # NOTE:  Be sure to set na.strings="" as "NA" is a valid network name  
  
  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update,followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)
  if (inherits(result,"try-error")) { 
     err_msg <- geterrmessage()
     stop(paste("getStation.IrisClient:",err_msg, url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
     stop(paste("getStation.IrisClient:",err_msg, url))
  }

  if (header["status"] != "200" && header["status"] != "204" ) {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
        stop(paste("getStation.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("couldn't connect to host",ignore_case=TRUE))) {
        stop(paste("getStation.IrisClient: couldn't connect to host", url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getStation.IrisClient: Cannot open connection",url))
    } else {
        stop(paste("getStation.IrisClient: Unexpected http status code",header["status"],strtrim(err_msg,500), url))
    }
  }

  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon),add=TRUE)
  result <- try( DF <- utils::read.delim(txtcon,sep="|",col.names=colNames,colClasses=colClasses,na.strings=""),silent=TRUE)
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getStation.IrisClient: Cannot open the connection:",url))
    } else {
      stop(paste("getStation.IrisClient:",err_msg, url))
    } 
    
  }
  
  # No errors so proceed
  
  # Convert time strings
  DF$starttime <- as.POSIXct(DF$starttime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  DF$endtime <- as.POSIXct(DF$endtime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Return dataframe with rows ordered by network.station
  netsta <- paste(DF$network,DF$station,sep='.')
  return(DF[order(netsta),])
}

# All arguments specified
setMethod("getStation", signature(obj="IrisClient", 
                                  network="character", station="character", location="character",
                                  channel="character", starttime="POSIXct", endtime="POSIXct",
                                  includerestricted="logical",
                                  latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getStation.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  includerestricted, latitude, longitude, minradius, maxradius))

# includerestricted="missing", use NULL
setMethod("getStation", signature(obj="IrisClient", 
                                  network="character", station="character", location="character",
                                  channel="character", starttime="POSIXct", endtime="POSIXct",
                                  includerestricted="missing",
                                  latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getStation.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  includerestricted=NULL, latitude, longitude, minradius, maxradius))


################################################################################
# getChannel method returns a dataframe with information from the output
# of the fdsn station web service with "format=text&level=channel".
#
#   http://service.iris.edu/fdsnws/station/1/
#
# Example output:
#
# #Network | Station | Location | Channel | Latitude | Longitude | Elevation | Depth | Azimuth | Dip | Instrument | Scale | ScaleFreq | ScaleUnits | SampleRate | StartTime | EndTime
# IU|COR|10|LHZ|44.5855|-123.3046|110.0|0.0|0.0|-90.0|Trillium 240 broad band|1.98775E9|0.02|M/S|1.0|2011-01-15T07:00:00|2012-03-08T08:43:00
#
################################################################################

if (!isGeneric("getChannel")) {
  setGeneric("getChannel", function(obj, network, station, location, channel,
                                    starttime, endtime, includerestricted,
                                    latitude, longitude, minradius, maxradius) {
    standardGeneric("getChannel")
  })
}

getChannel.IrisClient <- function(obj, network, station, location, channel,
                                  starttime, endtime, includerestricted,
                                  latitude, longitude, minradius, maxradius) {
  
  # Parameters common to all 'station' webservice requests
  url <- paste(obj@site,obj@service_type,"station/1/query?",sep="/")
  url <- paste(url,"net=",ifelse(network=="","*",network),sep="")
  url <- paste(url,"&sta=",ifelse(station=="","*",station),sep="")
  # NOTE:  Blank locations containing two spaces must be converted to "--"
  location <- ifelse(location=="","*",location)
  url <- paste(url,"&loc=",stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",ifelse(channel=="","*",channel),sep="")
  url <- paste(url,"&starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&nodata=204",sep="")
  if (obj@service_type == "fdsnws") {
    if (!is.null(includerestricted)) {
       url <- paste(url,"&includerestricted=",tolower(includerestricted),sep="")
    }
  }
  url <- paste(url,"&format=text",sep="")
  
  # Add optional geographic constraints if they are passed in
  if (!missing(latitude)) {
    url <- paste(url,"&latitude=",latitude,sep="")      
  }
  if (!missing(longitude)) {
    url <- paste(url,"&longitude=",longitude,sep="")      
  }
  if (!missing(minradius)) {
    url <- paste(url,"&minradius=",minradius,sep="")      
  }
  if (!missing(maxradius)) {
    url <- paste(url,"&maxradius=",maxradius,sep="")      
  }
  
  # Parameters specific to the getChannel() method
  url <- paste(url,"&level=channel",sep="")
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Set up the colnames we wish to have in our dataframe
  # Network | Station | Location | Channel | Latitude | Longitude | Elevation | Depth | Azimuth | Dip |
  # Instrument | Scale | ScaleFreq | ScaleUnits | SampleRate | StartTime | EndTime
  colNames <- c("network","station","location","channel","latitude","longitude","elevation","depth","azimuth","dip",
                "instrument","scale","scalefreq","scaleunits","samplerate","starttime","endtime")
  colClasses <- c(rep("character",4),rep("numeric",6),"character",rep("numeric",2),"character","numeric",rep("character",2))
  
  # Make webservice request
  # NOTE:  Be sure to set na.strings="" as "NA" is a valid network name  
  
  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)

  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getChannel.IrisClient:",err_msg, url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getChannel.IrisClient:",err_msg, url))
  }

  if (header["status"] != "200" && header["status"] != "204") {
      err_msg <- gurlc
      if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
          stop(paste("getChannel.IrisClient: URL Not Found",url))
      } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
          stop(paste("getChannel.IrisClient: Cannot open connection",url))
      } else {
          stop(paste("getChannel.IrisClient: Unexpected http status code", header["status"], strtrim(err_msg,500), url))
      }
  }

  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon),add=TRUE)
  result <- try( DF <- utils::read.delim(txtcon,sep="|",col.names=colNames,colClasses=colClasses,na.strings=""), silent=TRUE)

  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getChannel.IrisClient: Cannot open connection",url))
     } else {
        stop(paste("getChannel.IrisClient:",err_msg, url))
     }
  }

  # No errors so proceed
  
  # Convert "  " location codes back into the "" that is used in the miniSEED record
  DF$location <- stringr::str_replace(DF$location,"  ","")
  # new station web service now returns blank loc codes, which convert to NA
  # switch NA's to "" as well
  DF$location[is.na(DF$location)] <- ""
  
  # Convert time strings
  DF$starttime <- as.POSIXct(DF$starttime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  DF$endtime <- as.POSIXct(DF$endtime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Add a snclId column
  DF$snclId <- paste(DF$network,DF$station,DF$location,DF$channel,sep=".")
  
  # Return dataframe with rows ordered by snclId
  return(DF[order(DF$snclId),])
}

# All arguments specified
setMethod("getChannel", signature(obj="IrisClient", 
                                  network="character", station="character", location="character",
                                  channel="character", starttime="POSIXct", endtime="POSIXct",
                                  includerestricted="logical",
                                  latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getChannel.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  includerestricted, latitude, longitude, minradius, maxradius))

# includerestricted="missing", use NULL
setMethod("getChannel", signature(obj="IrisClient", 
                                  network="character", station="character", location="character",
                                  channel="character", starttime="POSIXct", endtime="POSIXct",
                                  includerestricted="missing",
                                  latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getChannel.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                  includerestricted=NULL, latitude, longitude, minradius, maxradius))


################################################################################
# getAvailability method returns a dataframe with information from the output
# of the fdsn station web service with "format=text&level=channel".
# With additional parameters, this webservice returns information on all
# matching SNCLs that have available data.
#
# The fdsnws/station web service will return space characters for location
# codes that are SPACE SPACE.
#
#   http://service.iris.edu/fdsnws/station/1/
#
# #Network | Station | Location | Channel | Latitude | Longitude | Elevation | Depth | Azimuth | Dip | Instrument | Scale | ScaleFreq | ScaleUnits | SampleRate | StartTime | EndTime
# CU|ANWB|00|LHZ|17.66853|-61.78557|39.0|0.0|0.0|-90.0|Streckeisen STS-2 Standard-gain|2.43609E9|0.05|M/S|1.0|2010-02-10T18:35:00|2599-12-31T23:59:59
#
################################################################################

if (!isGeneric("getAvailability")) {
  setGeneric("getAvailability", function(obj, network, station, location, channel,
                                         starttime, endtime, includerestricted,
                                         latitude, longitude, minradius, maxradius) {
    standardGeneric("getAvailability")
  })
}

getAvailability.IrisClient <- function(obj, network, station, location, channel,
                                       starttime, endtime, includerestricted,
                                       latitude, longitude, minradius, maxradius) {

  # Parameters common to all 'station' webservice requests
  url <- paste(obj@site,obj@service_type,"station/1/query?",sep="/")
  url <- paste(url,"net=",ifelse(network=="","*",network),sep="")
  url <- paste(url,"&sta=",ifelse(station=="","*",station),sep="")
  # NOTE:  Blank locations containing two spaces must be converted to "--"
  location <- ifelse(location=="","*",location)
  url <- paste(url,"&loc=",stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",ifelse(channel=="","*",channel),sep="")
  url <- paste(url,"&starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS", tz="GMT"),sep="")
  url <- paste(url,"&nodata=204",sep="")
  if (obj@service_type != "ph5ws") {
    url <- paste(url,"&includerestricted=",ifelse(includerestricted,"true","false"),sep="")
  }
  url <- paste(url,"&format=text",sep="")
  
  # Add optional geographic constraints if they are passed in
  if (!missing(latitude)) {
    url <- paste(url,"&latitude=",latitude,sep="")      
  }
  if (!missing(longitude)) {
    url <- paste(url,"&longitude=",longitude,sep="")      
  }
  if (!missing(minradius)) {
    url <- paste(url,"&minradius=",minradius,sep="")      
  }
  if (!missing(maxradius)) {
    url <- paste(url,"&maxradius=",maxradius,sep="")      
  }
    
  # Parameters specific to the getAvailability() method
  if (obj@service_type != "ph5ws") {
    url <- paste(url,"&includeavailability=true",sep="")
    url <- paste(url,"&matchtimeseries=true",sep="")
  }
  url <- paste(url,"&level=channel",sep="")

  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Set up the colnames we wish to have in our dataframe
  # Network | Station | Location | Channel | Latitude | Longitude | Elevation | Depth | Azimuth | Dip |
  # Instrument | Scale | ScaleFreq | ScaleUnits | SampleRate | StartTime | EndTime
  colNames <- c("network","station","location","channel","latitude","longitude","elevation","depth","azimuth","dip",
                "instrument","scale","scalefreq","scaleunits","samplerate","starttime","endtime")
  colClasses <- c(rep("character",4),rep("numeric",6),"character",rep("numeric",2),"character","numeric",rep("character",2))
  
  # Make webservice request
  # NOTE:  Be sure to set na.strings="" as "NA" is a valid network name

  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)

  if (inherits(result,"try-error")) {   
     err_msg <- geterrmessage()
     stop(paste("getAvailability.IrisClient:",err_msg, url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     stop(paste("getAvailability.IrisClient:",err_msg, url))
  }

  if (header["status"] != "200" && header["status"] != "204" ) {
     err_msg <- gurlc
     if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
          stop(paste("getAvailability.IrisClient: URL Not Found",url))
     } else if (stringr::str_detect(err_msg, regex("couldn't connect to host",ignore_case=TRUE))) {
          stop(paste("getAvailability.IrisClient: couldn't connect to host", url))
     } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
          stop(paste("getAvailability.IrisClient: Cannot open connection",url))
     } else {
          stop(paste("getAvailability.IrisClient: Unexpected http status code",header["status"],strtrim(err_msg,500), url))
     }
  }

  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon), add=TRUE)
  result <- try( DF <- utils::read.delim(txtcon,sep="|",col.names=colNames,colClasses=colClasses,na.strings=""), silent=TRUE)

  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getAvailability.IrisClient: Cannot open connection",url))
     } else {
        stop(paste("getAvailability.IrisClient:",err_msg, url))
     }
  } 

  # No errors so proceed

  # Filter out unwanted channels -- first to come to mind is LOG, but others get added by recommendation.
  DF <- DF[!(DF$channel %in% c("LOG", "ACE", "OCF")),]
  
  # Convert "  " location codes back into the "" that is used in the miniSEED record
  DF$location <- stringr::str_replace(DF$location,"  ","")
  # new station web service now returns blank loc codes, which convert to NA
  # switch NA's to "" as well
  DF$location[is.na(DF$location)] <- ""

  # Convert time strings
  DF$starttime <- as.POSIXct(DF$starttime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  DF$endtime <- as.POSIXct(DF$endtime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Add a snclId column
  DF$snclId <- paste(DF$network,DF$station,DF$location,DF$channel,sep=".")
  
  # Return dataframe with rows ordered by snclId
  return(DF[order(DF$snclId),])
}

# All arguments specified
setMethod("getAvailability", signature(obj="IrisClient", 
                                       network="character", station="character", location="character",
                                       channel="character", starttime="POSIXct", endtime="POSIXct",
                                       includerestricted="logical",
                                       latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getAvailability.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                       includerestricted, latitude, longitude, minradius, maxradius))

# includerestricted="missing", use FALSE
setMethod("getAvailability", signature(obj="IrisClient", 
                                       network="character", station="character", location="character",
                                       channel="character", starttime="POSIXct", endtime="POSIXct",
                                       includerestricted="missing",
                                       latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getAvailability.IrisClient(obj, network, station, location, channel, starttime, endtime, 
                                       FALSE, latitude, longitude, minradius, maxradius))


################################################################################
# getUnavailability method returns a dataframe with those channels that are found
# in the getChannel() dataframe but not in the getAvailability() dataframe.
################################################################################

if (!isGeneric("getUnavailability")) {
  setGeneric("getUnavailability", function(obj, network, station, location, channel,
                                           starttime, endtime, includerestricted,
                                           latitude, longitude, minradius, maxradius) {
    standardGeneric("getUnavailability")
  })
}

getUnavailability.IrisClient <- function(obj, network, station, location, channel,
                                         starttime, endtime, includerestricted,
                                         latitude, longitude, minradius, maxradius) {
  
  # Get all channels
  c <- getChannel(obj, network, station, location, channel,
                  starttime, endtime, includerestricted,
                  latitude, longitude, minradius, maxradius)
  
  # Get available channels
  a <- getAvailability(obj, network, station, location, channel,
                       starttime, endtime, includerestricted,
                       latitude, longitude, minradius, maxradius)
  
  # Create unique record identifiers (SNCL is enough)
  c_sncls <- paste(c$network,c$station,c$location,c$channel,sep=".")
  a_sncls <- paste(a$network,a$station,a$location,a$channel,sep=".")
  
  unavailable_mask <- !(c_sncls %in% a_sncls)
  return(c[unavailable_mask,])
}
  
# All arguments specified
setMethod("getUnavailability", signature(obj="IrisClient", 
                                         network="character", station="character", location="character",
                                         channel="character", starttime="POSIXct", endtime="POSIXct",
                                         includerestricted="logical",
                                         latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getUnavailability.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                         includerestricted, latitude, longitude, minradius, maxradius))

# includerestricted="missing", use FALSE
setMethod("getUnavailability", signature(obj="IrisClient", 
                                         network="character", station="character", location="character",
                                         channel="character", starttime="POSIXct", endtime="POSIXct",
                                         includerestricted="missing",
                                         latitude="ANY", longitude="ANY", minradius="ANY", maxradius="ANY"), 
          function(obj, network, station, location, channel, starttime, endtime,
                   includerestricted, latitude, longitude, minradius, maxradius) 
            getUnavailability.IrisClient(obj, network, station, location, channel, starttime, endtime, 
                                         FALSE, latitude, longitude, minradius, maxradius))


################################################################################
# getDataAvailability method returns a dataframe with information from the output
# of the iris availability web service with "format=text&level=channel".
#
# http://service.iris.edu/fdsnws/availability/1/
#
################################################################################
if (!isGeneric("getDataAvailability")) {
  setGeneric("getDataAvailability", function(obj, network, station, location, channel, starttime, endtime, 
                                              mergequality, mergesamplerate, mergeoverlap, mergetolerance, 
                                              includerestricted, excludetoolarge){
    standardGeneric("getDataAvailability")
  })
}

getDataAvailability.IrisClient <- function(obj, network, station, location, channel, starttime, endtime, 
                                            mergequality, mergesamplerate, mergeoverlap, mergetolerance, 
                                            includerestricted, excludetoolarge) {

  url <- paste(obj@site,obj@service_type,"availability/1/query?",sep="/")
  url <- paste(url,"net=",network,sep="")
  url <- paste(url,"&sta=",station,sep="")
  location <- ifelse(location=="","--",location)
  url <- paste(url,"&loc=", stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",channel,sep="")
  url <- paste(url,"&starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS6", tz="GMT"),sep="")
  url <- paste(url,"&format=geocsv",sep="")
  url <- paste(url,"&nodata=204",sep="")
  
  # Add optional arguments if they are found
  mergeflag <- 0
  if (missing(mergequality) || mergequality == TRUE) {
          url <- paste(url,"&merge=quality",sep="")
          mergequality <- TRUE
          mergeflag <- 1
  } 
  
  if (!missing(mergesamplerate) && mergesamplerate == TRUE) {
       if (mergeflag == 0) {
              url <- paste(url,"&merge=samplerate",sep="")
              mergeflag <- 1
        } else {
              url <- paste(url,",samplerate",sep="")
        }
  } else {
       mergesamplerate <- FALSE
  }  # default is FALSE

  
  if (missing(mergeoverlap) || mergeoverlap == TRUE) {
          if (mergeflag == 0) {
                url <- paste(url,"&merge=overlap",sep="")
                mergeflag <- 1
          } else {
                url <- paste(url,",overlap",sep="")
          }
  } # default is TRUE
  
  if (!missing(mergetolerance)) {
         url <- paste(url,"&mergegaps=",mergetolerance,sep="")
  } # default is 1.5 sample rate
  
  if (!missing(includerestricted)) {
    url <- paste(url,"&includerestricted=",includerestricted,sep="")
  } else {
    url <- paste(url,"&includerestricted=TRUE",sep="")
  } # default is TRUE
  
  if (!missing(excludetoolarge) && excludetoolarge == TRUE) {
    url <- paste(url,"&limit=500000",sep="")
  } # default is FALSE
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Set up the colnames we wish to have in our dataframe
  # Network | Station | Location | Channel | Quality | SampleRate | StartTime | EndTime
  # Network | Station | Location | Channel | SampleRate | StartTime | EndTime
  if (mergequality == FALSE) {
      if (mergesamplerate == TRUE) {
         colNames <- c("network","station","location","channel","quality","starttime","endtime")
         colClasses <- c(rep("character",7))
      } else {
         colNames <- c("network","station","location","channel","quality","samplerate","starttime","endtime")
         colClasses <- c(rep("character",8))
      }
  } else {
      if (mergesamplerate == TRUE) {
         colNames <- c("network","station","location","channel","starttime","endtime")
         colClasses <- c(rep("character",6))
      } else {
         colNames <- c("network","station","location","channel","samplerate","starttime","endtime")
         colClasses <- c(rep("character",7))
      }
  }

  # Make webservice request
  # NOTE:  Be sure to set na.strings="" as "NA" is a valid network name
  
  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)
  
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getDataAvailability.IrisClient:", strtrim(err_msg,500), url))
  }
  
  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getDataAvailability.IrisClient:",err_msg, url))
  }
  
  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
      stop(paste("getDataAvailability.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getDataAvailability.IrisClient: Cannot open connection",url))
    } else if (stringr::str_detect(err_msg, regex("Error 500: Internal Server Error"))) {
      err_msg <- stringr::str_replace_all(err_msg, "[\r\n\t]","")
      stop(paste("getDataAvailability.IrisClient: Internal Server Error:", stringr::str_match(err_msg,"Error 500: Internal Server Error(.+)Usage")[,2], url))
    } else {
      stop(paste("getDataAvailability.IrisClient: Unexpected http status code", header["status"], strtrim(err_msg,500),url))
    }
  }
  
  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon), add=TRUE)
  result <- try( DF <- utils::read.delim(txtcon,sep="|",col.names=colNames,colClasses=colClasses,na.strings="",skip=4), silent=TRUE)
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getDataAvailability.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getDataAvailability.IrisClient:", err_msg, url))
    }
  }
  
  # No errors so proceed
  # Filter out unwanted channels -- first to come to mind is LOG, but others get added by recommendation.
  DF <- DF[!(DF$channel %in% c("LOG", "ACE", "OCF")),]
  
  # Convert "  " location codes back into the "" that is used in the miniSEED record
  DF$location <- stringr::str_replace(DF$location,"  ","")
  DF$location[is.na(DF$location)] <- ""
  
  # Convert time strings
  DF$starttime <- as.POSIXct(DF$starttime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  DF$endtime <- as.POSIXct(DF$endtime, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Add a snclId column
  DF$snclId <- paste(DF$network,DF$station,DF$location,DF$channel,sep=".")
  
  # Return dataframe with rows ordered by snclId
  return(DF[order(DF$snclId),])
}  
 

# All required arguments specified
setMethod("getDataAvailability", signature(obj="IrisClient",
                                       network="character", station="character", location="character",
                                       channel="character", starttime="POSIXct", endtime="POSIXct",
                                       mergequality="ANY",mergesamplerate="ANY",mergeoverlap="ANY",
                                       mergetolerance="ANY",
                                       includerestricted="ANY",excludetoolarge="ANY"),
          function(obj, network, station, location, channel, starttime, endtime,
                   mergequality,mergesamplerate,mergeoverlap,mergetolerance,includerestricted,excludetoolarge)
            getDataAvailability.IrisClient(obj, network, station, location, channel, starttime, endtime,
                                       mergequality,mergesamplerate,mergeoverlap,mergetolerance,includerestricted,excludetoolarge))



################################################################################
# getEvalresp method returns instrument response data from the evalresp webservice:
#
#   http://service/irisws/evalresp/1/
#
################################################################################

if (!isGeneric("getEvalresp")) {
  setGeneric("getEvalresp", function(obj, network, station, location, channel, time,
                                     minfreq, maxfreq, nfreq, units, output, spacing) {
     standardGeneric("getEvalresp")
  })
}

getEvalresp.IrisClient <- function(obj, network, station, location, channel, time, 
                                   minfreq, maxfreq, nfreq, units, output, spacing) {
  
  # TODO:  getEvalresp should test for wildcards in network, station, location, channel
  # TODO:  and return an error if any are found.
  if (obj@service_type == "ph5ws") {
      url <- paste(obj@site,"ph5ws/evalresp/1/query?",sep="/")
  } else {
      url <- paste(obj@site,"irisws/evalresp/1/query?",sep="/")
  }
  url <- paste(url,"net=",network,sep="")
  url <- paste(url,"&sta=",station,sep="")
  # NOTE:  Locations with blanks must be converted into "--" when creating the URL
  # NOTE:  For getEvalresp, convert "" to "--"
  location <- ifelse(location=="","--",location)
  url <- paste(url,"&loc=", stringr::str_replace(location,"  ","--"),sep="")
  url <- paste(url,"&cha=",channel,sep="")
  # NOTE:  a single 'time' parameter is used rather than 'starttime' and 'endtime'
  url <- paste(url,"&time=",format(time,"%Y-%m-%dT%H:%M:%OS0", tz="GMT"),sep="") # ws_evalresp requires "T" format
  if (missing(output)) {
    output <- "fap"
  }
  url <- paste(url,"&output=",output,sep="")      
  
  # Add optional arguments if they are found
  if (!missing(minfreq)) {
    url <- paste(url,"&minfreq=",minfreq,sep="")      
  }
  if (!missing(maxfreq)) {
    url <- paste(url,"&maxfreq=",maxfreq,sep="")      
  }
  if (!missing(nfreq)) {
    url <- paste(url,"&nfreq=",nfreq,sep="")      
  }
  if (!missing(units)) {
    url <- paste(url,"&units=",units,sep="")      
  }
  if (!missing(spacing)) {
    url <- paste(url,"&spacing=",spacing,sep="")  
  }
 
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Handle requests for either freq-amp-phase or freq-real-imag
  if (output == "fap") {
    colNames <- c("freq","amp","phase")
  } else if (output == "cs") {
    colNames <- c("freq","real","imag")
  } else {
    stop(paste("getEvalresp.IrisClient: bad output arg = '",output,"' -- must be 'fap' or 'cs'"))
  }
  
  # Conversion of URL into a data frame is a single line with utils::read.table().

  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)

  if (inherits(result,"try-error")) {  
     err_msg <- geterrmessage()
     stop(paste("getEvalresp.IrisClient:", strtrim(err_msg,500), url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     stop(paste("getEvalresp.IrisClient:",err_msg, url))
  }

  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
        stop(paste("getEvalresp.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getEvalresp.IrisClient: Cannot open connection",url))
    } else if (stringr::str_detect(err_msg, regex("Error 500: Internal Server Error"))) {
        err_msg <- stringr::str_replace_all(err_msg, "[\r\n\t]","")
        stop(paste("getEvalresp.IrisClient: Internal Server Error:", stringr::str_match(err_msg,"Error 500: Internal Server Error(.+)Usage")[,2], url))
    } else {
        stop(paste("getEvalresp.IrisClient: Unexpected http status code", header["status"], strtrim(err_msg,500),url))
    }
  }
  
  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon), add=TRUE)
  result <- try ( DF <- utils::read.table(txtcon, col.names=colNames), silent=TRUE )
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getEvalresp.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getEvalresp.IrisClient:", err_msg, url))
    }
  }

  # No errors so proceed
  
  # Return the dataframe, guaranteeing that it is ordered by frequency
    
  return(DF[order(DF$freq),])
}

# All required arguments specified
setMethod("getEvalresp", signature(obj="IrisClient", 
                                   network="character", station="character", location="character",
                                   channel="character", time="POSIXct",
                                   minfreq="ANY", maxfreq="ANY", nfreq="ANY", units="ANY",
                                   output="ANY",spacing="ANY"), 
          function(obj, network, station, location, channel, time, 
                   minfreq, maxfreq, nfreq, units, output,spacing) 
            getEvalresp.IrisClient(obj, network, station, location, channel, time, 
                                   minfreq, maxfreq, nfreq, units, output,spacing))


################################################################################
# getEvent method returns seismic event data from the event webservice:
#
#   https://earthquake.usgs.gov/fdsnws/event/1/
#
# TODO:  The getEvent method could be fleshed out with a more complete list
# TODO:  of arguments to be used as ws-event parameters.
################################################################################

if (!isGeneric("getEvent")) {
  setGeneric("getEvent", function(obj, starttime, endtime, minmag, maxmag, magtype,
                                  mindepth, maxdepth) {
    standardGeneric("getEvent")
  })
}

getEvent.IrisClient <- function(obj, starttime, endtime, minmag, maxmag, magtype,
                                mindepth, maxdepth) {
  
  if(stringr::str_detect(obj@site,regex("service.*.iris.edu"))) {
     url <- "https://earthquake.usgs.gov/fdsnws/event/1/query?"
  } else {
     url <- paste(obj@site,"/fdsnws/event/1/query?",sep="/")
  }

  url <- paste(url,"starttime=",format(starttime,"%Y-%m-%dT%H:%M:%OS0", tz="GMT"),sep="")
  url <- paste(url,"&endtime=",format(endtime,"%Y-%m-%dT%H:%M:%OS0", tz="GMT"),sep="")
  url <- paste(url,"&format=text",sep="")
  
  # Add optional arguments if they are non-null
  if (!missing(minmag)) {
    url <- paste(url,"&minmag=",minmag,sep="")      
  }
  if (!missing(maxmag)) {
    url <- paste(url,"&maxmag=",maxmag,sep="")      
  }
  if (!missing(magtype)) {
    url <- paste(url,"&magtype=",magtype,sep="")      
  }
  if (!missing(mindepth)) {
    url <- paste(url,"&mindepth=",mindepth,sep="")      
  }
  if (!missing(maxdepth)) {
    url <- paste(url,"&maxdepth=",maxdepth,sep="")      
  }
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # https://earthquake.usgs.gov/fdsnws/event/1/query?starttime=2013-02-01T00:00:00&endtime=2013-02-02T00:00:00&minmag=5&format=text
  #
  # #EventID | Time | Latitude | Longitude | Depth | Author | Catalog | Contributor | ContributorID | MagType | Magnitude | MagAuthor | EventLocationName
  # 4075900|2013-02-01T22:18:33|-11.12|165.378|10.0|NEIC|NEIC PDE|NEIC PDE-Q||MW|6.4|GCMT|SANTA CRUZ ISLANDS
  
  # Assign column names and classes for the returned data
  colNames <- c("eventId","time","latitude","longitude","depth","author","cCatalog","contributor",
                "contributorId","magType","magnitude","magAuthor","eventLocationName")
  colClasses <- c("character","character","numeric","numeric","numeric","factor","factor","factor",
                  "factor","factor","numeric","factor","character")
    
  # Conversion of URL into a data frame is a single line with read.table().

  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE) 

  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     stop(paste("getEvent.IrisClient:",err_msg, url))
  }
  
  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
     err_msg <- geterrmessage()
     stop(paste("getEvent.IrisClient:",err_msg, url))
  }

  if (header["status"] == "503" || header["status"] == "500") {
     Sys.sleep(3)
     h <-  RCurl::basicTextGatherer()
     result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)
     if (inherits(result,"try-error")) {
         stop(paste("getEvent.IrisClient:",err_msg, url))
     }
     result <- try(header <- RCurl::parseHTTPHeader(h$value()))
     if (inherits(result,"try-error")) {
         err_msg <- geterrmessage()
         stop(paste("getEvent.IrisClient:",err_msg, url))
     }
  }

  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("service unavailable",ignore_case=TRUE)) || header["status"] == "503") {
        stop(paste("getEvent.IrisClient: Service Unavailable", url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getEvent.IrisClient: Cannot open connection",url))
    } else if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
        stop(paste("getEvent.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("couldn't connect to host",ignore_case=TRUE))) {
        stop(paste("getEvent.IrisClient: Couldn't connect to host", url))
    } else if (header["status"] != "200" && header["status"] != "204") {
        stop(paste("getEvent.IrisClient: Unexpected http status code",header["status"],err_msg, url))
    }

  }
  
  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon), add=TRUE)
  result <- try ( DF <- utils::read.table(txtcon, sep="|", quote="", col.names=colNames, colClasses=colClasses),silent=TRUE )
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getEvent.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getEvent.IrisClient:",err_msg,url))
    } 
    
  }
  
  # Last check to make sure DF is defined
  if (!exists('DF')) {
    stop(paste("getEvent.IrisClient: No Data Found"))            
  }
    
  # No errors so proceed
  
  # Final data conversion
  DF$time <- as.POSIXct(DF$time, "%Y-%m-%dT%H:%M:%OS", tz="GMT")
  
  # Return dataframe with rows ordered by time
  return(DF[order(DF$time),])
}
  
# All arguments specified
setMethod("getEvent", signature(obj="IrisClient", 
                                   starttime="POSIXct", endtime="POSIXct",
                                   minmag="ANY", maxmag="ANY", magtype="ANY",
                                   mindepth="ANY", maxdepth="ANY"), 
          function(obj, starttime, endtime, minmag, maxmag, magtype, mindepth, maxdepth) 
            getEvent.IrisClient(obj, starttime, endtime, minmag, maxmag, magtype, mindepth, maxdepth))


################################################################################
# getTraveltime method returns a dataframe with information from the traveltime
# webservice:
#
#   http://service.iris.edu/irisws/traveltime/1/
#
################################################################################

if (!isGeneric("getTraveltime")) {
  setGeneric("getTraveltime", function(obj, latitude, longitude, depth, staLatitude, staLongitude) {
    standardGeneric("getTraveltime")
  })
}

getTraveltime.IrisClient <- function(obj, latitude, longitude, depth, staLatitude, staLongitude) {
  
  # Create URL arguments from incoming parameters
  evloc <- paste("[", latitude, ",", longitude, "]", sep="")
  staloc <- paste("[", staLatitude, ",", staLongitude, "]", sep="")
  
  # Assemble URL
  url <- paste(obj@site,"/irisws/traveltime/1/query?",sep="")
  url <- paste(url,"&evloc=",evloc,sep="")
  url <- paste(url,"&evdepth=",depth,sep="")
  url <- paste(url,"&staloc=", staloc, sep="")
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # http://service.iris.edu/irisws/traveltime/1/query?evloc=[-11.12,165.378]&evdepth=10.0&staloc=[-30.4183,151.6293]
  #
  #   Model: iasp91
  #   Distance   Depth   Phase   Travel    Ray Param  Takeoff  Incident  Purist    Purist
  #     (deg)     (km)   Name    Time (s)  p (s/deg)   (deg)    (deg)   Distance   Name 
  #   -----------------------------------------------------------------------------------
  #   23.14    10.0   P        306.34    10.542     33.42    33.36    23.14   = P
  #   23.14    10.0   P        306.88     9.162     28.60    28.55    23.14   = P
  #   23.14    10.0   P        308.47     9.679     30.38    30.32    23.14   = P
  #   23.14    10.0   PcP      534.45     2.082      6.25     6.24    23.14   = PcP
  #   23.14    10.0   S        558.79    16.323     29.61    29.55    23.14   = S
  #   23.14    10.0   S        560.09    19.178     35.48    35.42    23.14   = S
  #   23.14    10.0   S        563.00    17.678     32.35    32.29    23.14   = S
  #   23.14    10.0   S        575.53    23.885     46.29    46.20    23.14   = S
  #   23.14    10.0   S        575.59    23.797     46.07    45.98    23.14   = S
  #   23.14    10.0   ScS      978.54     3.844      6.68     6.67    23.14   = ScS
  #   23.14    10.0   PKiKP    998.81     0.511      1.53     1.53    23.14   = PKiKP
  #   23.14    10.0   SKiKS   1422.54     0.570      0.99     0.99    23.14   = SKiKS
  
  # Assign column names and classes for the returned data
  colNames <- c("distance", "depth", "phaseName", "travelTime", "rayParam",
                "takeoff", "incident", "puristDistance", "dummy", "puristName")
  colClasses <- c("numeric", "numeric", "factor", "numeric", "numeric",
                  "numeric", "numeric", "numeric", "character", "character")
  
  # Conversion of URL into a data frame is a single line with read.table().

  h <-  RCurl::basicTextGatherer()
  result <- try(gurlc <- RCurl::getURL(url,useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),silent=TRUE)

  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getTraveltime.IrisClient:",err_msg, url))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getTraveltime.IrisClient:",err_msg, url))
  }

  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- gurlc
    if (stringr::str_detect(err_msg, regex("couldn't connect to host",ignore_case=TRUE))) {
        stop(paste("getTraveltime.IrisClient: Couldn't connect to host", url))
    } else if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
        stop(paste("getTraveltime.IrisClient: URL Not Found",url))
    } else if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
        stop(paste("getTraveltime.IrisClient: Cannot open connection",url))
    } else {
        stop(paste("getTraveltime.IrisClient: Unexpected http status code",header["status"],strtrim(err_msg,500), url))
    }
  }
  
  if(length(gurlc) == 0) { gurlc <- "" }
  txtcon <- textConnection(gurlc)
  on.exit(close(txtcon), add=TRUE)
  result <- try ( returnValue <- utils::read.table(txtcon, skip=4, col.names=colNames, colClasses=colClasses),silent=TRUE )
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    if (stringr::str_detect(err_msg, regex("cannot open the connection",ignore_case=TRUE))) {
      stop(paste("getTraveltime.IrisClient: Cannot open connection",url))
    } else {
      stop(paste("getTraveltime.IrisClient:",err_msg, url))
    } 
  }
  
  # No errors so proceed
  
  # Only use the first seven columns
  DF <- returnValue[,c(1:8,10)]
  
  # Return dataframe with rows ordered by travelTime
  return(DF[order(DF$travelTime),])
}

# All arguments specified
setMethod("getTraveltime", signature(obj="IrisClient", 
                                latitude="numeric", longitude="numeric", depth="numeric",
                                staLatitude="numeric", staLongitude="numeric"), 
          function(obj, latitude, longitude, depth, staLatitude, staLongitude) 
            getTraveltime.IrisClient(obj, latitude, longitude, depth, staLatitude, staLongitude))


################################################################################
# getDistaz method returns a dataframe with information from the distaz
# webservice:
#
#   http://service.iris.edu/irisws/distaz/1/
#
################################################################################

if (!isGeneric("getDistaz")) {
  setGeneric("getDistaz", function(obj, latitude, longitude, staLatitude, staLongitude) {
    standardGeneric("getDistaz")
  })
}

getDistaz.IrisClient <- function(obj, latitude, longitude, staLatitude, staLongitude) {
  
  # Assemble URL
  url <- paste(obj@site,"/irisws/distaz/1/query?",sep="")
  url <- paste(url,"&evtlat=",latitude,sep="")
  url <- paste(url,"&evtlon=",longitude,sep="")
  url <- paste(url,"&stalat=", staLatitude, sep="")
  url <- paste(url,"&stalon=", staLongitude, sep="")
  
  # Write debug output
  if (obj@debug) {
    write(paste("<debug>URL =",url), stdout())
  }
  
  # Get data from distaz web service

  h <-  RCurl::basicTextGatherer()
  result <- try( distazXml <- RCurl::getURL(url, useragent=obj@useragent,.opts = list(headerfunction = h$update, followlocation = TRUE, low.speed.time=300, low.speed.limit=1, connecttimeout=300)),
                 silent=TRUE)
  
  # Handle error response
  if (inherits(result,"try-error")) { 
    err_msg <- geterrmessage()
    stop(paste("getDistaz.IrisClient:", err_msg))
  }

  result <- try(header <- RCurl::parseHTTPHeader(h$value()))
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getDistaz.IrisClient:", err_msg))
  }

  if (header["status"] != "200" && header["status"] != "204") {
    err_msg <- distazXml
    if (stringr::str_detect(err_msg, regex("Not Found",ignore_case=TRUE)) || header["status"] == "404") {
        stop(paste("getDistaz.IrisClient: URL Not Found:",url))
    } else if (stringr::str_detect(err_msg, regex("connect to host",ignore_case=TRUE))) {
        stop(paste("getDistaz.IrisClient: Could not connect to host", url))
    } else if (stringr::str_detect(err_msg, regex("Error", ignore_case=TRUE))) {
        err_msg <- stringr::str_extract(err_msg,"Error (.+)")
        stop(paste("getDistaz.IrisClient: Error",err_msg, url))
    } else if (nchar(distazXml)==0) {
        stop(paste("getDistaz.IrisClient: returned empty string", url))
    } else {
        stop(paste("getDistaz.IrisClient: Unexpected http status code",header["status"], strtrim(err_msg,500) ,url))
    }
  }
      
  # No errors so proceed
  
  # http://service.iris.edu/irisws/distaz/1/query?stalat=0.0&stalon=0.0&evtlat=15.0&evtlon=0.0
  #
  # <DistanceAzimuth>
  #   <azimuth>180.0</azimuth>
  #    <backAzimuth>0.0</backAzimuth>
  #    <distance>14.90407</distance>
  #  </DistanceAzimuth>

  # See this example for magic with the XML package:
  #
  #  http://www.omegahat.net/RSXML/gettingStarted.html
  
  #  IRISWS distaz xml output became more compicated on 2016/08/17. Simple leaf node parsing no longer works.
  #  new output for http://service.iris.edu/irisws/distaz/1/query?stalat=0.0&stalon=0.0&evtlat=15.0&evtlon=0.0 looks like:
  #
  # <DistanceAzimuth>
  #   <ellipsoid name="WGS84">
  #      <semiMajorAxis>6378137</semiMajorAxis>
  #      <flattening>1/298.257223563</flattening>
  #   </ellipsoid>
  #   <fromlat>15.0</fromlat>
  #   <fromlon>0.0</fromlon>
  #   <tolat>0.0</tolat>
  #   <tolon>0.0</tolon>
  #   <azimuth>180.0</azimuth>
  #   <backAzimuth>0.0</backAzimuth>
  #   <distance>14.90407</distance>
  #  </DistanceAzimuth>

  #  old code:
  #  doc <- XML::xmlRoot(XML::xmlTreeParse(distazXml)) 
  #  namedValueStrings <- XML::xmlSApply(doc,XML::xmlValue)
  #  DF <- as.data.frame(t(as.numeric(namedValueStrings)))
  #  names(DF) <- names(namedValueStrings)
  
  # new code:
  result <- try( xmlList <- XML::xmlToList(distazXml), silent=TRUE)
  if (inherits(result,"try-error")) {
    err_msg <- geterrmessage()
    stop(paste("getDistaz.IrisClient:", err_msg))
  } 
  xmlNames <- names(xmlList)
  xmlList <- c(xmlList["ellipsoid"],sapply(xmlList[xmlNames[! xmlNames %in% c("ellipsoid")]], as.numeric))
  DF <- as.data.frame(xmlList)
  colnames(DF)[colnames(DF)=="ellipsoid..attrs"] <- "ellipsoid.name"

  return(DF)
}

# All arguments specified
setMethod("getDistaz", signature(obj="IrisClient", 
                                 latitude="numeric", longitude="numeric",
                                 staLatitude="numeric", staLongitude="numeric"), 
          function(obj, latitude, longitude, staLatitude, staLongitude) 
            getDistaz.IrisClient(obj, latitude, longitude, staLatitude, staLongitude))