Plug-in still depends on deprecated (and removed) Apache Commons HttpClient

[kwisatz]

The Apache Commons HttpClient has been deprecated for a while and removed from Jenkins. See e.g. this ticket for a similar issue with another plug-in.

See also: #337

Due to this, notifications back to Phabricator/Phorge now fail with the following Exception:

java.lang.ClassNotFoundException: org.apache.commons.httpclient.HttpMethod
	at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:476)
	at jenkins.util.URLClassLoader2.findClass(URLClassLoader2.java:35)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:589)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
Caused: java.lang.NoClassDefFoundError: org/apache/commons/httpclient/HttpMethod
	at com.uber.jenkins.phabricator.PhabricatorNotifier.getUberallsClient(PhabricatorNotifier.java:303)
	at com.uber.jenkins.phabricator.PhabricatorNotifier.perform(PhabricatorNotifier.java:136)
	at jenkins.tasks.SimpleBuildStep.perform(SimpleBuildStep.java:123)
	at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:101)
	at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:71)
	at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution.lambda$start$0(SynchronousNonBlockingStepExecution.java:47)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:829)

E.g. in such a step:

post {
        always {
          script {
                step([$class: 'PhabricatorNotifier', commentOnSuccess: false, commentWithConsoleLinkOnFailure: true])
          }
        }
}

A plug-in exists for version 3.x of httpclient, but not for the version 4.x used by this plug-in.

Additional resources that may be of interest:

• https://plugins.jenkins.io/apache-httpcomponents-client-4-api/
• https://hc.apache.org/httpclient-legacy/
• https://issues.jenkins.io/browse/JENKINS-70253

[dereckson]

According jenkinsci/jenkins#7312, two upgrade paths are offered to plugin maintainers:

• migrate code to the native Java 11 HTTP client
• update dependencies to depend on the legacy Commons HttpClient 3.x API plugin

The Commons HttpClient plugin used in Jenkins core was actually a patched version of 3.x, not a 4.x.

See also https://openjdk.org/groups/net/httpclient/intro.html for an intorduction to the Java HTTP Client.

[betterphp]

I've submitted a PR that fixes this, although based on the comments on https://issues.jenkins.io/browse/JENKINS-70253 it seems there's nobody to approved it :/