NodeJS Base Images

This repository contains source of base Node.JS images. Includes build configuration for latest 6.x, 7.x and 8.x releases. This is based on the Base RHEL Atomic 7 image.

The Dockerfile makes use of the environment variable NODE_VERSION to determine what version of node is installed during build. This is done via ENV and not ARG as OpenShift Docker Strategy does not support build args as of OCP 3.5. This should be available in 3.6+.

The environment is configured via the build-config.yaml file for each stream. OpenShift, when using the Docker Build Strategy, injects an ENV statement after the FROM statement. This allows the use of this variable through the build.

Managing Configuration

In order to assist with the management of related configuration, a Makefile is provided that uses the OpenShift Client to install/replace/delete the configuration in a specified namespace (default is openshift).

Example Usage

# delete any existing configuration (build, imagestream)
make clean

# install configuration for all streams
make install

# if installing to your namespace
make NAMESPACE=$(whoami) install

Node.JS S2I Builder Images

This repository also stores the configuration required for building and using the source-to-image flavors of the above mentioned base images.

Caution: These images are dependent on the base images, as they expect and use, variables like S2I_DESTINATION, OPENSHIFT_SOURCE_DIR, OPENSHIFT_DEPLOYMENTS_DIR etc. to be available in the runtime environment (with the container) as defined in Dockerfile.s2i.

S2I Assemble Script

Configuration

The assemble script provides the following customizations.

Debug Mode

Specifying the DEBUG environment variable will run the assemble stage of the source-to-image process with the following changes.

• executes set -x to enable bash tracing
• uses -v flag when using mv or cp commands
• prints out debug level log messages

NPM Logging

Specifying the NPM_CONFIG_LOGLEVEL with a valid value (eg: info, debug etc.) will override the default (info). This will make npm quiet chatty and hence is not switched to debug when DEBUG env var is set, so use with caution.

NPM Install Arguments

NPM install command arguments can be specified by setting the NPM_INSTALL_ARGS environment variable with the desired value.

NPM Post Install Scripts

Once npm install is executed, you can if desired execute additional scripts by providing a space separated list of target scripts via the NPM_SCRIPT_POST_INSTALL environment variable.

Webpack Builds

For builds that use webpack, couple of options are available.

Specifying a script name NPM_SCRIPT_WEBPACK environment variable, triggers an npm run <script> command. This is triggered after post install scripts are run (see above). This can also be provided as the last post install target.

Specifying the WEBPACK_DEPLOY environment variable, ensures that only the <prefix>/dist directory is copied to the OPENSHIFT_DEPLOYMENTS_DIR after build completes. This is useful if you plan on using extended builds.

Test Execution

Following the test strategies defined for S2I builds, the assemble script allows for optional test execution before pruning or cleanup occurs to ensure that developer/test dependencies are available for test execution. This is done by specifying NPM_SCRIPT_TEST as a valid npm script target.

Caution: If you choose the postCommit hook strategy, be sure that you are not pruning the dependencies required (NPM_SKIP_PRUNE).

S2I Run Script

The default run script provided will, switch to the the OPENSHIFT_DEPLOYMENTS_DIR and execute npm start. You can configure the npm command to execute by specifying NPM_START environment variable and any arguments to start by specifying NPM_START_ARGS environment variable.

Extended Builds

A nifty feature of OpenShift build (via source-to-image) is extended builds. The following snippent demonstrates how this can be used, in this particular case a Node.JS codebase is built using the Source strategy within the nodejs-7-s2i image. Once the assemble stage is completed, artifacts from /opt/openshift is copied over to opt/openshift in an instance of nodejs-7 container for s2i run stage. Note that the relative path is used in the latter.

strategy:
  type: Source
  sourceStrategy:
    from:
      kind: ImageStreamTag
      namespace: openshift
      name: 'nodejs-7-s2i:latest'
    runtimeImage:
      kind: "ImageStreamTag"
      name: "nodejs-7:latest"
      namespace: openshift
    runtimeArtifacts:
      - sourcePath: "/opt/openshift"
        destinationDir: "opt/"
      - sourcePath: /usr/libexec/s2i
        destinationDir: usr/libexec/

Local S2I Build Example

To use these source-to-image containers to build a working copy of your Node.JS source, you can execute the following command.

s2i build -e DEBUG=1 -e NPM_SCRIPT_TEST=test <path/to/working/copy> <registry>/<namespace>/nodejs-6-s2i:latest local/my-super-app

The following example shows how an runtime image can be used.

s2i build \
  . \
  docker-registry/openshift/nodejs-7-s2i:latest \
  --runtime-image docker-registry./openshift/nodejs-7:latest \
  --runtime-artifact /opt/openshift:opt/openshift \
  --runtime-artifact /usr/libexec/s2i:usr/libexec/s2i \
  local/my-awesome-app