R/operateDSVM.R

In Azure/AzureDSVM: Create and Manage Azure Data Science Virtual Machine(s) for Convenient Execution of Scalable and Elastic Analytics.

#' Operations on a data science virtual machine. 
#' Available operations are "Check", "Start", "Stop", and "Delete".
#' 
#' @inheritParams deployDSVM
#' 
#' @param operation Operations on the DSVM. Available operations are 
#' "Check", "Start", "Stop", "Delete", which check the status of, 
#' start running, stop running, and delete a DSVM, respectively.
#' 
#' @export
operateDSVM <- function(context,
                        resource.group,
                        hostname,
                        operation="Check") {
  # check if token is valid.

  AzureSMR::azureCheckToken(context)

  # check input arguments.

  if (missing(context)) {
    stop("Please specify AzureSMR context.")
    assert_that(AzureSMR::is.azureActiveContext(context))
  }
  
  if (missing(resource.group)) {
    stop("Please specify resource group.")
    assert_that(AzureSMR:::is_resource_group(resource.group))
  }
  
  if(missing(hostname)) {
    stop("Please specify virtual machine hostname(s).")
    assert_that(all(sapply(hostname, AzureSMR:::is_vm_name)))
  }
  
  if (missing(operation)) {
    stop("Please specify an operation on the DSVM")
    operation <- match.arg(operation, c("Check", "Start", "Stop", "Delete"))
  } 

  # check if vm exists.

  vm_names <- AzureSMR::azureListVM(context,
                                    resourceGroup=resource.group,
                                    verbose=FALSE)
  
  if(!all(hostname %in% unlist(vm_names$name)))
    stop("Given DSVM(s) does not exist in resource group.")
  
  status <- AzureSMR::azureVMStatus(azureActiveContext=context,
                                    resourceGroup=resource.group,
                                    vmName=hostname,
                                    verbose=FALSE)
  
  if (operation == "Start") {
    if(status == "Provisioning succeeded, VM running") {
      message("The DSVM has already been started.")
    } else {
      AzureSMR::azureStartVM(azureActiveContext=context,
                             resourceGroup=resource.group,
                             vmName=hostname,
                             verbose=FALSE)
      status <- "Provisioning succeeded, VM running"
    }
  } else if (operation == "Stop") {
    if(status == "Provisioning succeeded, VM deallocated") {
      message("The DSVM has already been stopped.")
    } else {
      AzureSMR::azureStopVM(azureActiveContext=context,
                            resourceGroup=resource.group,
                            vmName=hostname,
                            verbose=FALSE)
      status <- "Provisioning succeeded, VM deallocated"
    }
  } else if (operation == "Delete") {
    status <- AzureSMR::azureDeleteVM(azureActiveContext=context,
                                      resourceGroup=resource.group,
                                      vmName=hostname,
                                      verbose=FALSE)
  } else {
  }
  
  return(status)
}

# Stop all DSVMs under subscription.

#' @inheritParams deployDSVM
#' 
#' @export

stopDSVMAll <- function(context, 
                        location,
                        resource.group="") {
  # check if token is valid.

  AzureSMR::azureCheckToken(context)

  # check input arguments.

  if (missing(context)) {
    stop("Please specify AzureSMR context.")
    assert_that(AzureSMR::is.azureActiveContext(context))
  }
  
  if (resource.group == "") {
    rgs <- azureListRG(context)
    
    for (i in 1:nrow(rgs)) {
      location <- rgs$location[i]
      rg       <- rgs$name[i]
      
      vms <- azureListVM(context, rg, location)
      
      for (j in 1:nrow(vms)) {
        vm <- vms$name[j]
        
        operateDSVM(context, rg, vm, operation="Stop")
      }
    }
  } else {
    rg <- resource.group
    
    vms <- azureListVM(context, rg, location)
    
    for (j in 1:nrow(vms)) {
      vm <- vms$name[j]
      
      operateDSVM(context, rg, vm, operation="Stop")
    }
  }
  
  return(TRUE)
}