nodejs: Add 'build' and 'prune' lifecycle events (#841)

* nodejs: Add 'build' and 'prune' lifecycle events

* Add libssl and ca-certificates dependencies to prod image

* Document build and prune stages in README

* Fix typo

incubator/nodejs/README.md

@@ -40,6 +40,20 @@ Templates are used to create your local project and start your development. When
 
     **NOTE:** Currently the `appsody deploy` command only works for deploying web applications.
 
+## Customizing the build
+
+Simple Node projects do not require a 'build' process: they are executed directly from source.  However, some technologies such as TypeScript require commands to be invoked to prepare the project ready to be run.
+
+If your project's dependencies require an additional build step, you can do so as follows:
+
+- In your `package.json`, edit the `"scripts"` section and define two new scripts:
+  - `"build": "npm install && <build commands>"`
+  - `"prune": "<cleanup commands> && npm prune"`
+
+When initially launching your app using `appsody run`, or building the production image with `appsody build`, the 'build' script is executed (if one exists).  Your build script should invoke `npm install` if any dependencies specified in your `devDependencies` are required as part of the build process - such as command line tools.
+
+When generating the production image, the 'prune' script is executed after that, if it exists, and is run with the `--production` flag.  This allows the removal of development dependencies that were required during the 'build' step.  This could be as simple as running the `npm prune` command, which inherits the production flag, and restores the dependencies to a production state.  You may also use this step to clean up any build artifacts that are not necessary in your production image.
+
 ## License
 
 This stack is licensed under the [Apache 2.0](./image/LICENSE) license

incubator/nodejs/image/Dockerfile-stack

@@ -8,7 +8,7 @@ ENV APPSODY_WATCH_DIR=/project/user-app
 ENV APPSODY_WATCH_IGNORE_DIR=/project/user-app/node_modules
 ENV APPSODY_WATCH_REGEX="^.*.js$"
 
-ENV APPSODY_PREP="npm install"
+ENV APPSODY_PREP="npm install && npm run build --if-present"
 
 ENV APPSODY_RUN="npm start --node-options --require=appmetrics-dash/attach"
 ENV APPSODY_RUN_ON_CHANGE="npm start --node-options --require=appmetrics-dash/attach"

incubator/nodejs/image/project/Dockerfile

@@ -8,14 +8,29 @@ RUN rm -rf /project/user-app/node_modules && mkdir -p /project/user-app/node_mod
 
 # Install user-app dependencies
 WORKDIR /project/user-app
-RUN npm install --production 
+RUN npm install --production
+
+# Run a build phase. Projects that need to execute build commands can customize the
+# 'build' script in their package.json. The build script should call 'npm install'.
+# If no build is required, just install production dependencies.
+RUN npm run build --if-present
+
+# Uninstall dev dependencies, leaving only production dependencies. Projects can
+# customize the 'prune' script in their package.json.
+# Ideally this would just be 'npm prune', but this command does not have pre/post
+# hooks. Instead, the user's 'prune' script can itself call 'npm prune' in addition
+# to any additional actions required.
+RUN npm run prune --production --if-present
 
 # Creating a tar to work around poor copy performance when using buildah 1.9.0
 RUN cd / && tar czf project.tgz project
 
 # Copy the dependencies into a slim Node docker image
 FROM node:12-slim
 
+# Install common dependencies (TLS and CA support)
+RUN apt-get update && apt-get install -y libssl1.1 ca-certificates && apt-get clean
+
 # Copy project with dependencies
 COPY --chown=node:node --from=0 /project.tgz .
 RUN tar xf project.tgz && chown -R node:node project && rm project.tgz

incubator/nodejs/stack.yaml

@@ -1,5 +1,5 @@
 name: Node.js
-version: 0.3.7
+version: 0.4.0
 description: Runtime for Node.js applications
 license: Apache-2.0
 language: nodejs