Publish to NPM on Jenkins when a new tag is created (#55)

Jenkinsfile

@@ -15,4 +15,26 @@ node {
     nodeEnv.inside("-e HOME=${workspace}") {
         sh 'make test'
     }
+
+    if (isTag()) {
+        stage 'Publish'
+        nodeEnv.inside("-e HOME=${workspace}") {
+            withCredentials([
+                [$class: 'StringBinding', credentialsId: 'npm-token', variable: 'NPM_TOKEN']]) {
+
+                sh "echo '//registry.npmjs.org/:_authToken=${env.NPM_TOKEN}' >> \$HOME/.npmrc"
+                sh "npm publish"
+            }
+        }
+    }
+}
+
+boolean isTag() {
+    try {
+        sh 'git describe --exact-match --tags'
+        return true
+    } catch (Exception e) {
+        echo e.toString()
+        return false
+    }
 }

package.json

@@ -139,6 +139,7 @@
     "test": "gulp test-app",
     "preversion": "npm run test",
     "version": "make clean all && ./scripts/update-changelog.js && git add CHANGELOG.md",
-    "postversion": "git push && git push --tags && ./scripts/create-github-release.js"
+    "postversion": "git push && git push --tags && ./scripts/create-github-release.js",
+    "prepublish": "npm run-script build"
   }
 }