Backstage Functions

Backstage Functions is an Open Source Serverless Platform able to store and execute code.

Benefits

Your code will be executed in an isolated environment
You don't have to worry about infrastructure
Functions can be called at any time by any project

FAQ

Which languages are supported? Currently, only Javascript.
Is it based on events? Not yet.
How the code execution happens in an isolated way? It uses the Backstage Functions Sandbox.

Running locally without Docker

Requirements

Redis 3.0+
NodeJS 8.13.0

Download the project

git clone https://github.com/backstage/functions.git

Setup

make setup

Run

make run

Configuration

To format your log in json, please run:

export LOG_APP_FORMAT=json

Running locally via Docker

Requirements

Docker 1.12+
Docker compose 1.8+

Download docker-compose.yml

mkdir functions
cd functions
curl 'https://raw.githubusercontent.com/backstage/functions/master/docker-compose.yml' > docker-compose.yml

Run

docker-compose up

How to use

Function Structure

Your function will have a file, which you define any name you want, and it has to have a function called main, with two parameters: req and res. Req represents the Request and Res represents the Response. At the end of your code, you'll have to use the send method.

Example of a function

function main(req, res) {
  const name = (req.body && req.body.name) || "World"
  res.send({ say: `Hello ${name}!` })
}

Setting a function

To set your function, you can make a PUT request to /functions/:namespace/:name:

curl -i -X PUT http://localhost:8100/functions/example/hello-world \
    -H 'content-type: application/json' \
    -d '{"code":"function main(req, res) {\n  const name = (req.body && req.body.name) || \"World\"\n  res.send({ say: `Hello ${name}! Nice meeting you...` })\n}\n"}'

Ps: if it doesn't exists, it will be created

Deleting a function

To delete your function, you can make a DELETE request to /functions/:namespace/:name:

curl -i -X DELETE http://localhost:8100/functions/example/hello-world \
    -H 'content-type: application/json'

Executing a function

To execute a function, you can make a PUT request to /functions/:namespace/:name/run:

curl -i -X PUT http://localhost:8100/functions/example/hello-world/run \
    -H 'content-type: application/json'

The result will be something like:

HTTP/1.1 200 OK
Content-Type: application/json; charset=utf-8
Content-Length: 22
ETag: W/"16-soBGetwJPBLt8CqWpBQu+A"
Date: Tue, 11 Oct 2016 16:51:04 GMT
Connection: keep-alive

{"say":"Hello World!"}

If one needs to pass an object in the request, the payload is executed:

curl -i -X PUT http://localhost:8100/functions/example/hello-world/run \
    -H 'content-type: application/json' \
    -d '{"name": "Pedro"}'

The result will be something like:

HTTP/1.1 200 OK
Content-Type: application/json; charset=utf-8
Content-Length: 22
ETag: W/"16-Ino2/umXaZ3xVEhoqyS8aA"
Date: Tue, 11 Oct 2016 17:13:11 GMT
Connection: keep-alive

{"say":"Hello Pedro!"}

Executing functions in a pipeline

To execute many functions in a pipeline, you can make a PUT request to /functions/pipeline:

// Function0
function main(req, res) {\
  res.send({x: req.body.x * 10});

}

// Function1
function main(req, res) {
  res.send({x: req.body.x * 20});
}

curl -g -i -X PUT 'http://localhost:8100/functions/pipeline?steps[0]=namespace/function0&steps[1]=namespace/function1' \
    -H 'content-type: application/json'
    -d '{"x": 1}'

Considering the curl above, the pipeline result would be like this:

HTTP/1.1 200 OK
Content-Type: application/json; charset=utf-8
Content-Length: 22
ETag: W/"16-Ino2/umXaZ3xVEhoqyS8aA"
Date: Tue, 11 Oct 2016 17:13:11 GMT
Connection: keep-alive

{"x": 200}