nodejs-example-extension

Example Extension in Node.js

The provided code sample demonstrates how to get a basic extension written in Node.js 12 up and running.

Note: This extension requires the Node.js 12 runtime to be present in the Lambda execution environment of your function.

There are two components to this sample:

• extensions/: This sub-directory should be extracted to /opt/extensions where the Lambda platform will scan for executables to launch extensions
• nodejs-example-extension/: This sub-directory should be extracted to /opt/nodejs-example-extension which is referenced by the extensions/nodejs-example-extension executable and includes a nodejs executable along with all of its necessary dependencies.

Prep Extension Dependencies

Install the extension dependencies locally, which will be mounted along with the extension code.

$ cd nodejs-example-extension
$ chmod +x index.js
$ npm install
$ cd ..

Layer Setup Process

The extensions .zip file should contain a root directory called extensions/, where the extension executables are located and another root directory called nodejs-example-extension/, where the core logic of the extension and its dependencies are located.

Creating zip package for the extension:

$ chmod +x extensions/nodejs-example-extension
$ zip -r extension.zip .

Ensure that you have aws-cli v2 for the commands below. Publish a new layer using the extension.zip. The output of the following command should provide you a layer arn.

aws lambda publish-layer-version \
 --layer-name "nodejs-example-extension" \
 --region <use your region> \
 --zip-file  "fileb://extension.zip"

Note the LayerVersionArn that is produced in the output. eg. "LayerVersionArn": "arn:aws:lambda:<region>:123456789012:layer:<layerName>:1"

Add the newly created layer version to a Node.js 12 runtime Lambda function.

All these instructions were arranged together for convenience in deploy.sh

Function Invocation and Extension Execution

When invoking the function, you should now see log messages from the example extension similar to the following:

    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    EXTENSION Name: nodejs-example-extension State: Ready Events: [INVOKE,SHUTDOWN]
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    START RequestId: 9ca08945-de9b-46ec-adc6-3fe9ef0d2e8d Version: $LATEST
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    nodejs-example-extension launching extension
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    [nodejs-example-extension] Registering...
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    [nodejs-example-extension] Registered with ID: 6ec8756c-4830-458b-9dda-156e5dda1cc1
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    [nodejs-example-extension] Waiting for event...
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    [nodejs-example-extension] Received event: {"eventType": "INVOKE", "deadlineMs": 1596217195507, "requestId": "c6702194-cf88-4407-9040-4d524ce0af3b", "invokedFunctionArn": "", "tracing": {"type": "X-Amzn-Trace-Id", "value": ""}}
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    [nodejs-example-extension] Waiting for event...
    ...
    ...
    Function logs...
    ...
    ...
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    END RequestId: 9ca08945-de9b-46ec-adc6-3fe9ef0d2e8d
    XXXX-XX-XXTXX:XX:XX.XXX-XX:XX    REPORT RequestId: 9ca08945-de9b-46ec-adc6-3fe9ef0d2e8d Duration: 80.36 ms Billed Duration: 100 ms Memory Size: 128 MB Max Memory Used: 67 MB Init Duration: 297.83 ms