Don't load in last jenkins server

[Asgoret]

Hi! After the last update module doesn't load in the last jenkins docker image based on Centos latest.
Java version:

openjdk version "1.8.0_252"
OpenJDK Runtime Environment (build 1.8.0_252-b09)
OpenJDK 64-Bit Server VM (build 25.252-b09, mixed mode)

Is there any way to fix it?

UPD#1: Jenkins doesn't support java 14.
Documentation: https://www.jenkins.io/doc/administration/requirements/java/
Error:

SEVERE: Running with Java class version 58 which is not in the list of supported versions: [52, 55]. Run with the --enable-future-java flag to enable such behavior. See https://jenkins.io/redirect/java-support/
--
  | java.lang.UnsupportedClassVersionError: 58.0
  | at Main.verifyJavaVersion(Main.java:174)
  | at Main.main(Main.java:142)
  |  
  | Jenkins requires Java versions [8, 11] but you are running with Java 14 from /usr/lib/jvm/java-14-openjdk-14.0.1.7-2.rolling.el8.x86_64
  | java.lang.UnsupportedClassVersionError: 58.0
  | at Main.verifyJavaVersion(Main.java:174)
  | at Main.main(Main.java:142)

UPD#2: Plugin error:

java.io.IOException: Failed to load: Outbound WebHook for build events (0.3.0)
 - Java (14) or higher required

cc @tylerlong @jamiewastin @jc21

[antonystevens20]

@Asgoret if you install JDK 14 and follow the instructions for "Run with the --enable-future-java flag" per the instructions, Jenkins does run. It appears this plugin won't run otherwise.

[tsunamaru]

A quick and dirty solution is to downgrade dependencies.

diff --git a/build.gradle b/build.gradle
index 67c07bf..2b42e5f 100644
--- a/build.gradle
+++ b/build.gradle
@@ -4,7 +4,7 @@ plugins {
 }
 
 group 'org.jenkins-ci.plugins'
-version '0.3.0'
+version '0.3.1'
 description 'Outbound WebHook for Jenkins build events'
 
 jenkinsPlugin {
@@ -30,6 +30,6 @@ repositories {
 }
 
 dependencies {
-    compile 'com.alibaba:fastjson:1.2.71'
-    compile 'com.squareup.okhttp3:okhttp:4.7.2'
+    compile 'com.alibaba:fastjson:1.2.34'
+    compile 'com.squareup.okhttp3:okhttp:3.8.1'
 }

Although it's worked for me, I didn't test it much, so use at your own peril.

[marianobenes]

Im having the same issue, is there any way to redownload an old version of the plugin?

[Asgoret]

Im having the same issue, is there any way to redownload an old version of the plugin?

Use unsupported javas via --enable-future-java flag. We simply move from this plugin. Jenkins stability is a more high priority.

[tsunamaru]

@marianobenes you can download previous versions from releases page. Alternatively, you can use latest version with my patch above. Compile it by yourself or download my precompiled .xpi
Then simply go to Manage Plugins > Advanced > Upload plugin and click on downloaded .xpi

@Asgoret

Use unsupported javas via --enable-future-java flag

Very bad idea!

[Asgoret]

@marianobenes you can download previous versions from releases page. Alternatively, you can use latest version with my patch above. Compile it by yourself or download my precompiled .xpi
Then simply go to Manage Plugins > Advanced > Upload plugin and click on downloaded .xpi

@Asgoret

Use unsupported javas via --enable-future-java flag

Very bad idea!

Well... not my ;D

[antonystevens20]

Hey, don't blame me. That's literally the only way to get this plugin working on the latest code revision.

In other words, don't run this in production.

[Asgoret]

Hey, don't blame me. That's literally the only way to get this plugin working on the latest code revision.

In other words, don't run this in production.

Not blaming anyone. Sorry if I offend you. As a workaround it's fine.

[vwbusguy]

Is Java 14 a hard dependency? Is the plugin really not compatible with 8+ or was it just compiled with Java 14 without backward compatibility enabled in the compiler?

[vwbusguy]

It looks like ./gradlew build works with Java 8, so there doesn't appear to be a good reason for the hard Java 14 requirement. It looks like it just needs to be rebuilt and republished with backward compatibility or with jdk8.

[vwbusguy]

Here's the workaround. From a machine with jdk8 installed (check by running java -version - you may need to change your alternatives if you have jdk8 installed and there's a different version reported):

• Clone this repo
• Run ./gradlew build
• In Jenkins go to Manage Jenkins-> Manage Plugins-> Advanced-> Upload plugin
• Upload the build/libs/outbound-webhook.hpi file
• Restart Jenkins when it finishes installing

It should now be loaded successfully:

[Asgoret]

Here's the workaround. From a machine with jdk8 installed (check by running java -version - you may need to change your alternatives if you have jdk8 installed and there's a different version reported):

• Clone this repo
• Run ./gradlew build
• In Jenkins go to Manage Jenkins-> Manage Plugins-> Advanced-> Upload plugin
• Upload the build/libs/outbound-webhook.hpi file
• Restart Jenkins when it finishes installing

It should now be loaded successfully:

This workaroun breaks jenkins casc installations when you specify jenkins plugins via plugins installer and added several manual steps.

[vwbusguy]

That very well may be, but the plugin as it is is broken for all Jenkins installations on a supported Java version. If the author would recompile this with a supported JDK compatibility and release a new version, it would work for everyone.