S.Richmond S.Richmond - 2 months ago 28
Groovy Question

How can I perform HTTP POST requests from within a Jenkins Groovy script?

I need to be able to create simple HTTP POST request during our Jenkins Pipeline builds. However I cannot use a simple curl sh script as I need it to work on Windows and Linux nodes, and I don't wish to enforce more tooling installs on nodes if I can avoid it.

The Groovy library in use in the Pipeline plugin we're using should be perfect for this task. There is an extension available for Groovy to perform simple POSTs called http-builder, but I can't for the life of me work out how to make use of it in Jenkins' Groovy installation.

If I try to use Grapes Grab to use it within a Pipeline script I get an error failing to do so, as seen here.

@Grapes(
@Grab(group='org.codehaus.groovy.modules.http-builder', module='http-builder', version='0.7.1')
)


Maybe Grapes Grab isn't supported in the bundled version of Groovy Jenkins uses. Is it possible to simply download and add http-builder and its dependencies to the Jenkins Groovy installation that goes out to the nodes?

Answer

Perhaps I'm missing something, but why not just use standard java libraries that are already on the jenkins classpath?

import java.io.BufferedReader
import java.io.InputStreamReader
import java.io.OutputStreamWriter
import java.net.URL
import java.net.URLConnection

def sendPostRequest(urlString, paramString) {
    def url = new URL(urlString)
    def conn = url.openConnection()
    conn.setDoOutput(true)
    def writer = new OutputStreamWriter(conn.getOutputStream())

    writer.write(paramString)
    writer.flush()
    String line
    def reader = new BufferedReader(new     InputStreamReader(conn.getInputStream()))
    while ((line = reader.readLine()) != null) {
      println line
    }
    writer.close()
    reader.close()
}

sendPostRequest("http://www.something.com", "param1=abc&param2=def")