ci(jenkins): enable pipeline

.ci/Jenkinsfile

@@ -0,0 +1,54 @@
+#!/usr/bin/env groovy
+
+@Library('apm@current') _
+
+pipeline {
+  agent { label 'linux && immutable' }
+  environment {
+    REPO = 'apm-agent-php'
+    BASE_DIR = "src/go.elastic.co/apm/${env.REPO}"
+    NOTIFY_TO = credentials('notify-to')
+    JOB_GCS_BUCKET = credentials('gcs-bucket')
+  }
+  options {
+    timeout(time: 1, unit: 'HOURS')
+    buildDiscarder(logRotator(numToKeepStr: '20', artifactNumToKeepStr: '20', daysToKeepStr: '30'))
+    timestamps()
+    ansiColor('xterm')
+    disableResume()
+    durabilityHint('PERFORMANCE_OPTIMIZED')
+    rateLimitBuilds(throttle: [count: 60, durationName: 'hour', userBoost: true])
+    quietPeriod(10)
+  }
+  triggers {
+    issueCommentTrigger('(?i).*jenkins\\W+run\\W+(?:the\\W+)?tests(?:\\W+please)?.*')
+  }
+  stages {
+    stage('Checkout') {
+      options { skipDefaultCheckout() }
+      steps {
+        deleteDir()
+        gitCheckout(basedir: "${BASE_DIR}", githubNotifyFirstTimeContributor: true)
+        stash allowEmpty: true, name: 'source', useDefaultExcludes: false
+      }
+    }
+    stage('Build') {
+      options { skipDefaultCheckout() }
+      steps {
+        withGithubNotify(context: 'Build') {
+          deleteDir()
+          unstash 'source'
+          dir("${BASE_DIR}"){
+            sh script: 'docker build --tag apm-agent-php .', label: 'prepare docker image'
+            sh script: 'docker run --rm -t -v $(pwd):/app apm-agent-php', label: 'run docker container'
+          }
+        }
+      }
+    }
+  }
+  post {
+    cleanup {
+      notifyBuildResult()
+    }
+  }
+}

.ci/jobs/apm-agent-php-mbp.yml

@@ -0,0 +1,5 @@
+---
+- job:
+    name: apm-agent-php/apm-agent-php-mbp
+    display-name: APM Agent PHP
+    description: APM Agent PHP

.ci/jobs/apm-agent-php.yml

@@ -0,0 +1,4 @@
+---
+- job:
+    name: apm-agent-php
+    project-type: folder

.ci/jobs/defaults.yml

@@ -0,0 +1,57 @@
+---
+
+##### GLOBAL METADATA
+
+- meta:
+    cluster: apm-ci
+
+##### JOB DEFAULTS
+
+- job:
+    view: APM-CI
+    project-type: multibranch
+    logrotate:
+      numToKeep: 100
+    concurrent: true
+    node: linux
+    script-path: .ci/Jenkinsfile
+    scm:
+    - github:
+        branch-discovery: no-pr
+        discover-pr-forks-strategy: merge-current
+        discover-pr-forks-trust: permission
+        discover-pr-origin: merge-current
+        discover-tags: true
+        notification-context: 'apm-ci'
+        repo: apm-agent-php
+        repo-owner: elastic
+        credentials-id: 2a9602aa-ab9f-4e52-baf3-b71ca88469c7-UserAndToken
+        ssh-checkout:
+          credentials: f6c7695a-671e-4f4f-a331-acdce44ff9ba
+        build-strategies:
+        - tags:
+            ignore-tags-older-than: -1
+            ignore-tags-newer-than: -1
+        - regular-branches: true
+        - change-request:
+            ignore-target-only-changes: false
+        clean:
+          after: true
+          before: true
+        prune: true
+        shallow-clone: true
+        depth: 3
+        do-not-fetch-tags: true
+        submodule:
+          disable: false
+          recursive: true
+          parent-credentials: true
+          timeout: 100
+        timeout: '15'
+        use-author: true
+        wipe-workspace: 'True'
+    periodic-folder-trigger: 1d
+    prune-dead-branches: true
+    publishers:
+    - email:
+        recipients: infra-root+build@elastic.co

.dockerignore

@@ -0,0 +1,8 @@
+.ci
+.dockerignore
+.git
+.gitignore
+docker
+docs
+Dockerfile
+README.md

Dockerfile

@@ -0,0 +1,11 @@
+FROM wordpress:php7.3-fpm-alpine
+
+RUN apk --no-cache add build-base autoconf curl-dev
+
+WORKDIR /app/src/ext
+
+CMD phpize \
+    && ./configure --enable-elasticapm \
+    && make clean \
+    && make \
+    && make install