ErllambdaElixirExample

Demonstrates a simple HTTP endpoint using API Gateway. You have full access to the request and response payload, including headers and status code.

To scan a DynamoDB table, make a GET request. To put or delete an item, make a POST or DELETE request respectively, passing in the query parameters as input for DynamoDB API.

Usage

Clone repository

git clone https://github.com/alertlogic/erllambda_elixir_example.git
cd erllambda_elixir_example

Create package

To a package suitable for deployment, project should be compiled in an environment similar to an environment in which service is going to be started.

One of the options is to use docker. Docker image definitions with installed elixir can be found in erllambda docker repository.

If images are not yet available publicly in docker hub, they can be easily built locally:

git clone https://github.com/alertlogic/erllambda_docker.git
docker build -t erllambda:20.3 erllambda_docker/20
docker build -t erllambda:20.3-elixir erllambda_docker/elixir

To create a zip package fetch all dependencies into the current directory and run erllambda release mix task in docker container:

mix deps.get
docker run -it --rm -v `pwd`:/buildroot -w /buildroot -e MIX_ENV=prod erllambda:20.3-elixir mix erllambda.release

This should create erllambda_elixir_example.zip package in release directory:

_build/prod/rel/erllambda_elixir_example/releases/0.1.0/erllambda_elixir_example.zip

Deploy AWS stack

Create bucket

aws s3api create-bucket --bucket erllambda-elixir-example

Package artifacts

aws cloudformation package \
    --template-file etc/template.yaml \
    --output-template-file packaged.yaml \
    --s3-bucket erllambda-elixir-example

Deploy stack

aws cloudformation deploy --capabilities CAPABILITY_IAM \
    --template-file packaged.yaml \
    --stack-name erllambda-elixir-example

Call lambda

Once stack is successfully deployed it creates a publicly available API Gateway endpoint. To retrieve created endpoint value, describe stack and get the output value of the ApiURL endpoint:

aws cloudformation describe-stacks \
    --stack-name erllambda-elixir-example \
    --query 'Stacks[].Outputs'

This should return URL similar to https://fkwbu2l29x2.execute-api.us-east-1.amazonaws.com/Prod/MyResource/

Create item

http post https://fkwbu2l29x2.execute-api.us-east-1.amazonaws.com/Prod/MyResource \
    id==foo bar==quz

Get all items

http https://fkwbu2l29x2.execute-api.us-east-1.amazonaws.com/Prod/MyResource

[
    {
        "bar": "quz",
        "id": "foo"
    }
]

Delete an item

http delete https://fkwbu2l29x2.execute-api.us-east-1.amazonaws.com/Prod/MyResource \
    id==foo

Delete stack

When you do not need stack anymore you can delete it using the following command:

aws cloudformation delete-stack --stack-name erllambda-elixir-example