using groovy to invoke curl

invoke_curl.groovy

// Define cURL process with correct arguments.
def proc = "curl -o log/${day.format('yyyy-MM-dd')}.log "
           + "http://servername/import-data/${day.format('yyyy-MM-dd')}"
           .execute()
// cURL uses error output stream for progress output.
Thread.start { System.err << proc.err } 
// Wait until cURL process finished and continue with the loop.
proc.waitFor()