Add label trigger support

src/main/java/com/adobe/jenkins/github_pr_comment_build/GitHubPullRequestLabelCause.java

@@ -0,0 +1,68 @@
+package com.adobe.jenkins.github_pr_comment_build;
+
+import hudson.model.Cause;
+import org.jenkinsci.plugins.scriptsecurity.sandbox.whitelists.Whitelisted;
+import org.kohsuke.stapler.export.Exported;
+
+import java.io.Serializable;
+
+/**
+ * Created by Agyaey on 04/04/2023.
+ */
+public final class GitHubPullRequestLabelCause extends Cause implements Serializable {
+    private final String labelUrl;
+    private final String labellingAuthor;
+    private final String label;
+
+    /**
+     * Constructor.
+     *
+     * @param labelUrl        the URL for the GitHub Label
+     * @param labellingAuthor the author of the GitHub Label
+     * @param label           the body for the GitHub Label
+     */
+    public GitHubPullRequestLabelCause(String labelUrl, String labellingAuthor, String label) {
+        this.labelUrl = labelUrl;
+        this.labellingAuthor = labellingAuthor;
+        this.label = label;
+    }
+
+    @Whitelisted
+    @Override
+    public String getShortDescription() {
+        return "GitHub pull request Label";
+    }
+
+    /**
+     * Retrieves the URL for the GitHub Label for this cause.
+     *
+     * @return the URL for the GitHub Label
+     */
+    @Whitelisted
+    @Exported(visibility = 3)
+    public String getLabelUrl() {
+        return labelUrl;
+    }
+
+    /**
+     * Retrieves the author of the GitHub Label for this cause.
+     *
+     * @return the author of the GitHub Label
+     */
+    @Whitelisted
+    @Exported(visibility = 3)
+    public String getLabellingAuthor() {
+        return labellingAuthor;
+    }
+
+    /**
+     * Retrieves the body for the GitHub Label for this cause.
+     *
+     * @return the body for the GitHub Label
+     */
+    @Whitelisted
+    @Exported(visibility = 3)
+    public String getLabel() {
+        return label;
+    }
+}

src/main/java/com/adobe/jenkins/github_pr_comment_build/IssueLabelGHEventSubscriber.java

@@ -0,0 +1,208 @@
+package com.adobe.jenkins.github_pr_comment_build;
+
+import com.cloudbees.jenkins.GitHubRepositoryName;
+import hudson.Extension;
+import hudson.model.CauseAction;
+import hudson.model.Item;
+import hudson.model.Job;
+import hudson.security.ACL;
+import hudson.security.ACLContext;
+import jenkins.branch.BranchProperty;
+import jenkins.branch.MultiBranchProject;
+import jenkins.model.ParameterizedJobMixIn;
+import jenkins.scm.api.SCMSource;
+import jenkins.scm.api.SCMSourceOwner;
+import jenkins.scm.api.SCMSourceOwners;
+import net.sf.json.JSONObject;
+import org.jenkinsci.plugins.github.extension.GHEventsSubscriber;
+import org.jenkinsci.plugins.github_branch_source.GitHubSCMSource;
+import org.kohsuke.github.GHEvent;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import static com.google.common.collect.Sets.immutableEnumSet;
+import static hudson.security.ACL.as;
+import static org.kohsuke.github.GHEvent.PULL_REQUEST;
+
+/**
+ * This subscriber manages {@link GHEvent} Label.
+ */
+@Extension
+public class IssueLabelGHEventSubscriber extends GHEventsSubscriber {
+    /**
+     * Logger.
+     */
+    private static final Logger LOGGER = Logger.getLogger(IssueLabelGHEventSubscriber.class.getName());
+    /**
+     * Regex pattern for a GitHub repository.
+     */
+    private static final Pattern REPOSITORY_NAME_PATTERN = Pattern.compile("https?://([^/]+)/([^/]+)/([^/]+)");
+    /**
+     * Regex pattern for a pull request ID.
+     */
+    private static final Pattern PULL_REQUEST_ID_PATTERN = Pattern.compile("https?://[^/]+/[^/]+/[^/]+/pull/(\\d+)");
+
+    /**
+     * String representing the created action on labeled PR.
+     */
+    private static final String ACTION_LABELED = "labeled";
+
+    @Override
+    protected boolean isApplicable(Item item) {
+        if (item != null && item instanceof Job<?, ?>) {
+            Job<?, ?> project = (Job<?, ?>) item;
+            if (project.getParent() instanceof SCMSourceOwner) {
+                SCMSourceOwner owner = (SCMSourceOwner) project.getParent();
+                for (SCMSource source : owner.getSCMSources()) {
+                    if (source instanceof GitHubSCMSource) {
+                        return true;
+                    }
+                }
+            }
+        }
+        return false;
+    }
+
+    @Override
+    protected Set<GHEvent> events() {
+        return immutableEnumSet(PULL_REQUEST);
+    }
+
+    /**
+     * Handles Labels on pull requests.
+     *
+     * @param event   only label event
+     * @param payload payload of gh-event. Never blank
+     */
+    @Override
+    protected void onEvent(GHEvent event, String payload) {
+        JSONObject json = JSONObject.fromObject(payload);
+
+        // Make sure this issue is a PR
+        //final String pullRequestUrl = json.getJSONObject("pull_request").getString("html_url");
+        JSONObject pullRequest = json.getJSONObject("pull_request");
+        final String pullRequestUrl = pullRequest.getString("html_url");
+        Integer pullRequestId = pullRequest.getInt("number");
+        String labellingAuthor = json.getJSONObject("sender").getString("login");
+        LOGGER.fine(() -> String.format("PR Review Author: %s", labellingAuthor));
+
+        final Pattern pullRequestJobNamePattern = Pattern.compile("^PR-" + pullRequestId + "\\b.*$", Pattern.CASE_INSENSITIVE);
+
+        final String label = json.getJSONObject("label").getString("name");
+        final String labelUrl = json.getJSONObject("label").getString("url");
+
+        // Make sure the action is edited or created (not deleted)
+        String action = json.getString("action");
+        if (!ACTION_LABELED.equals(action)) {
+            LOGGER.log(Level.FINER, "Event is labeled ({0}) for PR {1}",
+                    new Object[]{action, pullRequestUrl}
+            );
+            return;
+        }
+
+        // Make sure the repository URL is valid
+        String repoUrl = json.getJSONObject("repository").getString("html_url");
+        Matcher matcher = REPOSITORY_NAME_PATTERN.matcher(repoUrl);
+        if (!matcher.matches()) {
+            LOGGER.log(Level.WARNING, "Malformed repository URL {0}", repoUrl);
+            return;
+        }
+        final GitHubRepositoryName changedRepository = GitHubRepositoryName.create(repoUrl);
+        if (changedRepository == null) {
+            LOGGER.log(Level.WARNING, "Malformed repository URL {0}", repoUrl);
+            return;
+        }
+
+        LOGGER.log(Level.FINE, "Received label on PR {0} for {1}", new Object[]{pullRequestId, repoUrl});
+        try (ACLContext aclContext = as(ACL.SYSTEM)) {
+            boolean jobFound = false;
+            Set<Job<?, ?>> alreadyTriggeredJobs = new HashSet<>();
+            for (final SCMSourceOwner owner : SCMSourceOwners.all()) {
+                for (SCMSource source : owner.getSCMSources()) {
+                    if (!(source instanceof GitHubSCMSource)) {
+                        continue;
+                    }
+                    GitHubSCMSource gitHubSCMSource = (GitHubSCMSource) source;
+                    if (gitHubSCMSource.getRepoOwner().equalsIgnoreCase(changedRepository.getUserName()) &&
+                            gitHubSCMSource.getRepository().equalsIgnoreCase(changedRepository.getRepositoryName())) {
+                        for (Job<?, ?> job : owner.getAllJobs()) {
+                            if (pullRequestJobNamePattern.matcher(job.getName()).matches()) {
+                                if (!(job.getParent() instanceof MultiBranchProject)) {
+                                    continue;
+                                }
+                                boolean propFound = false;
+                                for (BranchProperty prop : ((MultiBranchProject) job.getParent()).getProjectFactory().
+                                        getBranch(job).getProperties()) {
+                                    if (!(prop instanceof TriggerPRLabelBranchProperty)) {
+                                        continue;
+                                    }
+                                    propFound = true;
+                                    TriggerPRLabelBranchProperty branchProp = (TriggerPRLabelBranchProperty) prop;
+                                    String expectedLabel = branchProp.getLabel();
+                                    Pattern pattern = Pattern.compile(expectedLabel,
+                                            Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
+                                    if (pattern.matcher(label).matches()) {
+                                        if (alreadyTriggeredJobs.add(job)) {
+                                            ParameterizedJobMixIn.scheduleBuild2(job, 0,
+                                                    new CauseAction(new GitHubPullRequestLabelCause(
+                                                            labelUrl, labellingAuthor, label)));
+                                            LOGGER.log(Level.FINE,
+                                                    "Triggered build for {0} due to PR Label on {1}:{2}/{3}",
+                                                    new Object[]{
+                                                            job.getFullName(),
+                                                            changedRepository.getHost(),
+                                                            changedRepository.getUserName(),
+                                                            changedRepository.getRepositoryName()
+                                                    }
+                                            );
+                                        } else {
+                                            LOGGER.log(Level.FINE, "Skipping already triggered job {0}", new Object[]{job});
+                                        }
+                                    } else {
+                                        LOGGER.log(Level.FINER,
+                                                "Label does not match the trigger build label string ({0}) for {1}",
+                                                new Object[]{expectedLabel, job.getFullName()}
+                                        );
+                                    }
+                                    break;
+                                }
+
+                                if (!propFound) {
+                                    LOGGER.log(Level.FINE,
+                                            "Job {0} for {1}:{2}/{3} does not have a trigger PR Label branch property",
+                                            new Object[]{
+                                                    job.getFullName(),
+                                                    changedRepository.getHost(),
+                                                    changedRepository.getUserName(),
+                                                    changedRepository.getRepositoryName()
+                                            }
+                                    );
+                                }
+
+                                jobFound = true;
+                            } else { // failed to match 'pullRequestJobNamePattern'
+                                LOGGER.log(Level.FINE,
+                                        "Skipping job [{0}] as it does not match the 'PR-' pattern." +
+                                                "If this is unexpected, make sure the job is configured with a 'discover pull requests...' behavior (see README)",
+                                        new Object[]{job.getName()});
+                            }
+                        }
+                    }
+                }
+            }
+            if (!jobFound) {
+                LOGGER.log(Level.FINE, "PR label on {0}:{1}/{2} did not match any job",
+                        new Object[]{
+                                changedRepository.getHost(), changedRepository.getUserName(),
+                                changedRepository.getRepositoryName()
+                        }
+                );
+            }
+        }
+    }
+}

src/main/java/com/adobe/jenkins/github_pr_comment_build/TriggerPRLabelBranchProperty.java

@@ -0,0 +1,53 @@
+package com.adobe.jenkins.github_pr_comment_build;
+
+import hudson.Extension;
+import hudson.model.Job;
+import hudson.model.Run;
+import jenkins.branch.BranchProperty;
+import jenkins.branch.BranchPropertyDescriptor;
+import jenkins.branch.JobDecorator;
+import org.kohsuke.stapler.DataBoundConstructor;
+
+/**
+ * Allows a GitHub pull request comment to trigger an immediate build based on a comment string.
+ */
+public class TriggerPRLabelBranchProperty extends BranchProperty {
+    /**
+     * The comment body to trigger a new build on.
+     */
+    private final String label;
+
+    /**
+     * Constructor.
+     *
+     * @param label the comment body to trigger a new build on
+     */
+    @DataBoundConstructor
+    public TriggerPRLabelBranchProperty(String label) {
+        this.label = label;
+    }
+
+    /**
+     * The comment body to trigger a new build on.
+     *
+     * @return the comment body to use
+     */
+    public String getLabel() {
+        return this.label;
+    }
+
+    @Override
+    public <P extends Job<P, B>, B extends Run<P, B>> JobDecorator<P, B> jobDecorator(Class<P> clazz) {
+        return null;
+    }
+
+    @Extension
+    public static class DescriptorImpl extends BranchPropertyDescriptor {
+
+        @Override
+        public String getDisplayName() {
+            return Messages.TriggerPRLabelBranchProperty_trigger_on_pull_request_label();
+        }
+
+    }
+}

src/main/resources/com/adobe/jenkins/github_pr_comment_build/Messages.properties

@@ -1,3 +1,4 @@
 TriggerPRCommentBranchProperty.trigger_on_pull_request_comment=Trigger build on pull request comment
 TriggerPRUpdateBranchProperty.trigger_on_pull_request_update=Trigger build on pull request update
-TriggerPRReviewBranchProperty.trigger_on_pull_request_review=Trigger build on pull request review
+TriggerPRReviewBranchProperty.trigger_on_pull_request_review=Trigger build on pull request review
+TriggerPRLabelBranchProperty.trigger_on_pull_request_label=Trigger build on pull request label

src/main/resources/com/adobe/jenkins/github_pr_comment_build/TriggerPRLabelBranchProperty/config.jelly

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<?jelly escape-by-default='true'?>
+<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
+    <f:entry title="Label" field="label">
+        <f:textbox />
+    </f:entry>
+</j:jelly>

src/main/resources/com/adobe/jenkins/github_pr_comment_build/TriggerPRLabelBranchProperty/help-commentBody.html

@@ -0,0 +1,3 @@
+<div>
+    The Label to trigger a new build for a PR job when it is received.
+</div>

src/main/resources/com/adobe/jenkins/github_pr_comment_build/TriggerPRLabelBranchProperty/help.html

@@ -0,0 +1,4 @@
+<div>
+    This property will cause a job for a pull request (PR-*) to be triggered immediately when a label is placed
+    on the PR in GitHub.  This has no effect on jobs that are not for pull requests.
+</div>