ci: trigger Jenkins from release tooling commits

Author: ngallodev

Jenkinsfile

@@ -7,7 +7,20 @@ pipeline {
         timeout(time: 45, unit: 'MINUTES')
     }
 
+    parameters {
+        choice(name: 'TRIGGER_SOURCE', choices: ['manual', 'post-commit'], description: 'Build origin')
+    }
+
     stages {
+        stage('Trigger contract') {
+            steps {
+                script {
+                    if (!(params.TRIGGER_SOURCE in ['manual', 'post-commit'])) {
+                        error("unsupported trigger source: ${params.TRIGGER_SOURCE}")
+                    }
+                }
+            }
+        }
         stage('Build') {
             steps { sh 'scripts/build.sh' }
         }

scripts/jenkins-local-job.sh

@@ -23,6 +23,23 @@ cli() {
   fi
 }
 
+install_post_commit_hook() {
+  local hooks hook temporary
+  hooks="$root/.git/hooks"
+  hook="$hooks/post-commit"
+  mkdir -p "$hooks"
+  temporary="$(mktemp "$hooks/.post-commit.XXXXXX")"
+  cat > "$temporary" <<'EOF'
+#!/usr/bin/env bash
+set -u
+root="$(git rev-parse --show-toplevel 2>/dev/null)" || exit 0
+[[ "$(git -C "$root" branch --show-current 2>/dev/null)" == "release-tooling" ]] || exit 0
+nohup "$root/scripts/jenkins-local-job.sh" trigger-hook >/dev/null 2>&1 &
+EOF
+  chmod 700 "$temporary"
+  mv "$temporary" "$hook"
+}
+
 case "${1:-}" in
   configure)
     mkdir -p "$(dirname "$cli")"
@@ -34,14 +51,18 @@ case "${1:-}" in
     else
       cli create-job "$job_name" < "$root/scripts/jenkins-local-job.xml"
     fi
+    install_post_commit_hook
     echo "configured $job_name"
     ;;
   inspect)
     test -r "$config" && rg -n '<triggers|pollSCM|release-tooling|file://' "$config"
     ;;
   trigger)
-    cli build "$job_name" -s
+    cli build "$job_name" -p TRIGGER_SOURCE=manual -s
     echo "triggered $jenkins_url/job/$job_name/"
     ;;
-  *) echo "usage: $0 configure|inspect|trigger" >&2; exit 2 ;;
+  trigger-hook)
+    cli build "$job_name" -p TRIGGER_SOURCE=post-commit
+    ;;
+  *) echo "usage: $0 configure|inspect|trigger|trigger-hook" >&2; exit 2 ;;
 esac

scripts/jenkins-local-job.xml

@@ -2,6 +2,16 @@
 <flow-definition plugin="workflow-job">
   <description>Script-triggered codebase-memory-cli release-tooling build and test.</description>
   <properties>
+    <hudson.model.ParametersDefinitionProperty>
+      <parameterDefinitions>
+        <hudson.model.StringParameterDefinition>
+          <name>TRIGGER_SOURCE</name>
+          <defaultValue>manual</defaultValue>
+          <description>Build origin; post-commit hooks use post-commit.</description>
+          <trim>true</trim>
+        </hudson.model.StringParameterDefinition>
+      </parameterDefinitions>
+    </hudson.model.ParametersDefinitionProperty>
     <org.jenkinsci.plugins.workflow.job.properties.DisableConcurrentBuildsJobProperty>
       <abortPrevious>false</abortPrevious>
     </org.jenkinsci.plugins.workflow.job.properties.DisableConcurrentBuildsJobProperty>

tests/test_jenkins_artifact_contract.sh

@@ -3,6 +3,7 @@ set -euo pipefail
 
 root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 pipeline="$root/Jenkinsfile"
+job_script="$root/scripts/jenkins-local-job.sh"
 
 for required in \
   "Archive Linux CLI artifact" \
@@ -15,3 +16,14 @@ for required in \
     exit 1
   }
 done
+
+for required in "TRIGGER_SOURCE" "post-commit"; do
+  grep -Fq "$required" "$pipeline" || {
+    echo "missing Jenkins trigger contract: $required" >&2
+    exit 1
+  }
+  grep -Fq "$required" "$job_script" || {
+    echo "missing post-commit hook contract: $required" >&2
+    exit 1
+  }
+done