add jenkins files

Jenkinsfile

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+pipeline {
+    agent any
+
+    environment {
+        VERSION = VersionNumber([
+            versionNumberString: 
+                '${BUILDS_ALL_TIME}',
+            versionPrefix: '1.0.',
+            worstResultForIncrement: 'SUCCESS'
+        ])
+        publish = 0
+    }
+
+    stages {
+        stage('Setup') {
+            steps {
+                echo 'Setting up test environment'
+                sh 'npm ci'
+                sh 'nodejs jenkins.js ${VERSION}'
+                script {
+                    currentBuild.displayName = env.VERSION
+                }
+            }
+        }
+        stage('Testing') {
+            steps {
+                echo 'Running tests...'
+                sh 'npm test'
+            }
+        }
+    }
+    post {
+        success {
+            script {
+                publish = sh script: "git log -1 | grep '\\[no publish\\]'", returnStatus: true
+                if (publish != 0) {
+                  echo 'Deploying'
+                  sh 'npm publish'   
+                } else {
+                  echo 'Build successful, Commit not marked for deploying'
+                  currentBuild.result = "UNSTABLE"
+                }
+            }
+        }
+    }
+}

jenkins.js

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+const fs = require('fs')
+
+const pkg = JSON.parse(fs.readFileSync('package.json', 'utf-8'))
+pkg.version = process.argv[2]
+fs.writeFileSync('package.json', JSON.stringify(pkg, null, 2))