applets.rst

Applets

Note

Currently the |cdk| only supports applets published as JavaScript modules.

Applets are files in the YAML or JSON format that have the following root attribute, where MODULE can represent a local file, such as ./my-module, a local dependency, such as my-dependency, or a global module, such as @aws-cdk/aws-s3 and CLASS is the name of a class exported by the module.

applet: MODULE[:CLASS]

If CLASS is not specified, Applet is used as the default class name. Therefore, you need only refer to |cdk| construct libraries that export an Applet class by their library name.

The rest of the YAML file is applet-dependent. The object is passed as props when the applet object is instantiated and added to an |cdk| app created by cdk-applet-js.

Use cdk-applet-js applet to run the applet, create an |cdk| app, and use that with the |cdk| tools, as shown in the following example.

cdk --app "cdk-applet-js ./my-applet.yaml" synth

To make the applet file executable and use the host as a shebang on Unix-based systems, such as Linux, MacOS, or Windows Bash shell, create a script similar to the following.

#!/usr/bin/env cdk-applet-js

applet: aws-cdk-codebuild
source: arn:aws:codecommit:::my-repository
image: node:8.9.4
compute: large
build:
   - npm install --unsafe-perm
   - npm test
   - npm pack --unsafe-perm

To execute the applet and synthesize an |CFN| template, use the following command.

cdk synth --app "./build.yaml"

To avoid needing --app for every invocation, add the following entry to cdk.json.

{
   "app": "./build.yaml"
}