R/getValidationRules.R

In gandiwan/datim-validation: External validation routines for data payloads in DATIM

#' @export
#' @title Utility function for getting validation rules dynamically from DHIS2 and parsing them into a data frame
#' 
#' @description d2Parser will parse a compliant DHIS2 XML,JSON or CSV file and transform it into a standard data
#' frame which can be used in subsequent DATIM validation routines
#'
#' @return Returns a data frame of validation rules consisting of name, left and right side operators and strategies

getValidationRules<-function() {
  
url<-paste0(getOption("baseurl"),"api/validationRules.json?fields=id,name,description,leftSide[expression,missingValueStrategy],rightSide[expression,missingValueStrategy],operator,periodType&paging=false")
sig<-digest::digest(url,algo='md5', serialize = FALSE)
vr<-getCachedObject(sig)

if (is.null(vr)) {
expression.pattern<-"[a-zA-Z][a-zA-Z0-9]{10}(\\.[a-zA-Z][a-zA-Z0-9]{10})?"
#Get a copy of the metadata from the server
r<-httr::GET(url,httr::timeout(60))
r<- httr::content(r, "text")
vr<-jsonlite::fromJSON(r,flatten=TRUE)$validationRules
#Static predefined map of operators
op.map<-data.frame(x=c("greater_than_or_equal_to","greater_than","equal_to","not_equal_to","less_than_or_equal_to","less_than","exclusive_pair","compulsory_pair"),
                   y=c(">=",">","==","!=","<=","<","|","&"),stringsAsFactors=F)
#Strategies
strat.map<-data.frame(x=c("SKIP_IF_ANY_VALUE_MISSING","SKIP_IF_ALL_VALUES_MISSING","NEVER_SKIP"))
#Remap the operators
vr$operator<-plyr::mapvalues(vr$operator,op.map$x,op.map$y,warn_missing=FALSE)
#Remove decorations
vr$leftSide.expression<-gsub("[#{}]","",vr$leftSide.expression)
vr$rightSide.expression<-gsub("[#{}]","",vr$rightSide.expression)
#Count the left and right side operators
vr$rightSide.ops<-stringr::str_count(vr$rightSide.expression,expression.pattern)
vr$leftSide.ops<-stringr::str_count(vr$leftSide.expression,expression.pattern)
saveCachedObject(vr,sig)
  }

return(vr) 
}