jtblin/aws-mock-metadata repository overview

⁠aws-mock-metadata

The ec2 instance metadata service⁠ runs on each ec2 instance and provide an api to retrieve information about the running instance as well as getting credentials based on the IAM role.

I needed to run this service locally (in docker) in order to be able to troubleshoot issues with kubernetes⁠ with the aws provider. I found an existing python based service⁠ but for some reasons I couldn't get it to work in docker with my temporary credentials. I also needed additional features like being able to return an instance id, availability zone, etc. so after a few hours of fighting I decided to create this one.

Repo: https://github.com/jtblin/aws-mock-metadata⁠

⁠Docker quick start

docker run -it --rm -p 80:$(APP_PORT) -e APP_PORT=$(APP_PORT) -e AWS_ACCESS_KEY_ID=$(AWS_ACCESS_KEY_ID) \
		-e AWS_SECRET_ACCESS_KEY=$(AWS_SECRET_ACCESS_KEY) jtblin/aws-mock-metadata

In your other docker image, install iptables and have a startup script that point 169.254.169.254 to the docker host before starting your program:

iptables -t nat -A OUTPUT -d 169.254.169.254 -j DNAT --to-destination ${HOST}

⁠Development

⁠Configuration

Set the following environment variables or create a .env file with the following information:

• APP_PORT: port to run the container on (default 8080)
• AWS_ACCESS_KEY_ID: aws access key
• AWS_SECRET_ACCESS_KEY: aws secret access key
• AWS_SESSION_TOKEN: aws session token (optional)

⁠Dependencies

You need to have go installed locally.

Install Godep

go get github.com/tools/godep

⁠Run

Run it. This will run the bare server on localhost.

make build run

Run it on 169.254.169.254 on Mac OSX or linux.

make build run-macos
make build run-linux

Run in docker

make docker run-docker

⁠Todo

• Pass values for endpoints via command line arguments