AWS Lambda Custom Runtime Local API

AWS Lambda Runtime API for local testing of custom runtimes

This project runs an HTTP API that is intended to emulate the AWS Lambda Runtime Interface to enable local testing of custom runtimes.

Running

This utility is published as both a jar or Docker image.

Jar

Prerequisites:

• JRE/JDK 11

Grab the latest release and run:

java -jar aws-lambda-runtime-local-<version>.jar

Run on alternate port

java -jar -Druntime.port=8080 aws-lambda-runtime-local-<version>.jar

Docker

Dockerhub Link: https://hub.docker.com/r/c1phr/aws-lambda-runtime-local

docker run -p 9000:9000 c1phr/aws-lambda-runtime-local

Run on alternate port

docker run -p 8080:8080 -e RUNTIME_PORT=8080 c1phr/aws-lambda-runtime-local

Usage

This utility will expose endpoints that mirror the AWS Lambda Runtime interface:

GET http://localhost:9000/2018-06-01/runtime/invocation/next
POST http://localhost:9000/2018-06-01/runtime/invocation/$REQUEST_ID/response
POST http://localhost:9000/2018-06-01/runtime/invocation/$REQUEST_ID/error
POST http://localhost:9000/2018-06-01/runtime/init/error

In addition to an endpoint that allows you to stage request events for your runtime to invoke:

POST http://localhost:9000/event/next

The runtime will serve events that have been POSTed to the /event/next endpoint sequentially each time the /invocation/next endpoint is called (or will return an empty response when there is no pending event). Invocation requests will include headers to emulate the Lambda Runtime interface as well, and expects that Request IDs are included with calls to /response and /error just as the Lambda service would.

Environment Configuration

The following configuration options can be set to modify the behavior of the local runtime. Either JVM arguments or environment variables can be used depending on the environment (JVM vs Docker).

Effect	JVM Argument	Environment Variable
Set Runtime Port	runtime.port=8080	RUNTIME_PORT=8080
Enable Request/Response Debugging	runtime.debug=true	RUNTIME_DEBUG=true