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  1. Jenkins
  2. JENKINS-37759

Usage of @Initializer(after = InitMilestone.COMPLETED) in plugins breaks the initialization logic

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    Details

    • Type: Bug
    • Status: Resolved (View Workflow)
    • Priority: Critical
    • Resolution: Fixed
    • Component/s: core
    • Labels:
    • Environment:
      jenkins-2.7.3-rc
    • Similar Issues:

      Description

      The problem is in the Initializer code:

      /**
           * Indicates that the specified milestone is necessary before executing this initializer.
           *
           * <p>
           * This has the identical purpose as {@link #requires()}, but it's separated to allow better type-safety
           * when using {@link InitMilestone} as a requirement (since enum member definitions need to be constant.)
           */
          InitMilestone after() default STARTED;
      
          /**
           * Indicates that this initializer is a necessary step before achieving the specified milestone.
           *
           * <p>
           * This has the identical purpose as {@link #attains()}. See {@link #after()} for why there are two things
           * to achieve the same goal.
           */
          InitMilestone before() default COMPLETED;
      

      If an initializer overrides <code>after</code> as COMPLETED, hence we end up in the situation when (<code>before == after == COMPLETED</code>). In such case Jenkins' reactor can never succeed in the canRun() check, and finally we do not invoke "Initialization completed" milestone since the code requires the dependency to be executed. So we get into chicken-and-egg

      Sample script for the issue analysis:

      import hudson.init.InitMilestone; 
      import hudson.util.HttpResponses;
      import javax.servlet.http.HttpServletResponse;
      
      final Jenkins jenkins = Jenkins.getInstance();
      
      if (jenkins.getInitLevel().compareTo(InitMilestone.COMPLETED) < 0) {
        println "Error: Jenkins initialization has not reached the COMPLETED state. Current state is ${jenkins.getInitLevel()}"
        return HttpResponses.status(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
      }
      

      Examples:

      Proposed changes:

      • Add injected test, which verifies the startup InitMilestone of Jenkins
      • Make Jenkins robust against wrong definitions
      • Finally add support of Initializers after COMPLETED by introducing a transient milestone

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          Issue Links

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            oleg_nenashev Oleg Nenashev created issue -
            oleg_nenashev Oleg Nenashev made changes -
            Field Original Value New Value
            Issue Type Task [ 3 ] Bug [ 1 ]
            oleg_nenashev Oleg Nenashev made changes -
            Labels lts-candidate
            recampbell Ryan Campbell made changes -
            Remote Link This issue links to "PR (Web Link)" [ 14776 ]
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-37780 [ JENKINS-37780 ]
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-37772 [ JENKINS-37772 ]
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-37805 [ JENKINS-37805 ]
            oleg_nenashev Oleg Nenashev made changes -
            Priority Blocker [ 1 ] Major [ 3 ]
            oleg_nenashev Oleg Nenashev made changes -
            Summary After startup of the instance with many jobs1, the setup does not end up in the COMPLETED milestone Usage of @Initializer(after = InitMilestone.COMPLETED) in plugins breaks the initialization logic
            oleg_nenashev Oleg Nenashev made changes -
            Description It happens due to https://github.com/jenkinsci/jenkins/pull/2177/files, which makes COMPLETED dependent on the following logic:

            {code}
                        // All plugins are loaded. Now we can figure out who depends on who.
                         requires(PLUGINS_PREPARED).attains(COMPLETED).add("Resolving Dependant Plugins Graph", new Executable() {
                             @Override
                             public void run(Reactor reactor) throws Exception {
                                 resolveDependantPlugins();
                             }
                         });
            {code}

            In this case COMPLETED state logic does not depend on the Job loading state, hence COMPLETED milestone can be achieved before JOB_LOADED in the reactor. It may easily happen when Job loading takes MUCH time. In such case COMPLETED state gets overridden by JOB_LOADED.

            Sample script for the issue analysis:
            {code}
            import hudson.init.InitMilestone;
            import hudson.util.HttpResponses;
            import javax.servlet.http.HttpServletResponse;

            final Jenkins jenkins = Jenkins.getInstance();

            if (jenkins.getInitLevel().compareTo(InitMilestone.COMPLETED) < 0) {
              println "Error: Jenkins initialization has not reached the COMPLETED state. Current state is ${jenkins.getInitLevel()}"
              return HttpResponses.status(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            }
            {code}


            The problem is in the Initializer code:

            {code}
            /**
                 * Indicates that the specified milestone is necessary before executing this initializer.
                 *
                 * <p>
                 * This has the identical purpose as {@link #requires()}, but it's separated to allow better type-safety
                 * when using {@link InitMilestone} as a requirement (since enum member definitions need to be constant.)
                 */
                InitMilestone after() default STARTED;

                /**
                 * Indicates that this initializer is a necessary step before achieving the specified milestone.
                 *
                 * <p>
                 * This has the identical purpose as {@link #attains()}. See {@link #after()} for why there are two things
                 * to achieve the same goal.
                 */
                InitMilestone before() default COMPLETED;
            {code}

            If an initializer overrides <code>after</code> as COMPLETED, hence we end up in the situation when (<code>before == after == COMPLETED</code>). In such case Jenkins' reactor can never succeed in the canRun() check, and finally we do not invoke "Initialization completed" milestone since the code requires the dependency to be executed. So we get into chicken-and-egg

            Sample script for the issue analysis:
            {code}
            import hudson.init.InitMilestone;
            import hudson.util.HttpResponses;
            import javax.servlet.http.HttpServletResponse;

            final Jenkins jenkins = Jenkins.getInstance();

            if (jenkins.getInitLevel().compareTo(InitMilestone.COMPLETED) < 0) {
              println "Error: Jenkins initialization has not reached the COMPLETED state. Current state is ${jenkins.getInitLevel()}"
              return HttpResponses.status(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            }
            {code}

            Examples:
            * https://github.com/jenkinsci/extreme-notification-plugin/blob/0249acced3d5483841e06849a4481c47a7e28fe5/src/main/java/org/jenkinsci/plugins/extremenotification/ServerStateListener.java#L51 (JENKINS-37780)
            * https://github.com/jenkinsci/support-core-plugin/blob/3cc53c1af1d2332bf5c6396987fe1516880b81a8/src/main/java/com/cloudbees/jenkins/support/SupportPlugin.java#L409 (JENKINS-37772)

            Proposed changes:
            * Add injected test, which verifies the startup InitMilestone of Jenkins
            * Make Jenkins robust against wrong definitions
            * Finally add support of Initializers after COMPLETED by introducing a transient milestone
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-37807 [ JENKINS-37807 ]
            oleg_nenashev Oleg Nenashev made changes -
            Priority Major [ 3 ] Critical [ 2 ]
            oleg_nenashev Oleg Nenashev made changes -
            Labels lts-candidate
            oleg_nenashev Oleg Nenashev made changes -
            Labels startup
            oleg_nenashev Oleg Nenashev made changes -
            Assignee Oleg Nenashev [ oleg_nenashev ]
            oleg_nenashev Oleg Nenashev made changes -
            Status Open [ 1 ] In Progress [ 3 ]
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-37874 [ JENKINS-37874 ]
            oleg_nenashev Oleg Nenashev made changes -
            Resolution Fixed [ 1 ]
            Status In Progress [ 3 ] Resolved [ 5 ]
            oleg_nenashev Oleg Nenashev made changes -
            Link This issue is related to JENKINS-44453 [ JENKINS-44453 ]
            cloudbees CloudBees Inc. made changes -
            Remote Link This issue links to "CloudBees Internal OSS-1385 (Web Link)" [ 18721 ]

              People

              Assignee:
              oleg_nenashev Oleg Nenashev
              Reporter:
              oleg_nenashev Oleg Nenashev
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              0 Vote for this issue
              Watchers:
              3 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: