The Feather Protocol

The Feather Protocol describes the standard HTTP API supported by all Feather runtimes.

Version

This document describes the Feather Protocol, version 0.1.

The Protocol

Code Execution

The feather protocol supports three ways to execute code.

The first approach is to send the code as a payload.

$ curl -d 'print("hello, world!")' https://feather-app/runtimes/python
hello, world!

The second approach is to send the file as multi-part formdata. This allows sending one or more files for execution.

$ cat main.py
print("hello, world!")

$ curl -Fmain.py=@main.py https://feather-app/runtimes/python
hello, world!

The third approach is to send the payload as JSON.

$ cat payload.json
{
    "files": [
        {"name": "main.py", "contents": "print('hello, world!')"}
    ],
}
$ curl \
    -H 'Content-type: application/json' \
    -d @payload.json                    \
    https://feather-app/runtimes/python
hello, world!

Request and Response Headers

The feather protocol supports special headers to specify command-line arguments, environment variables and the entrypoint, the source file to execute.

The response includes headers to indicate the exit status and the time taken to execute the request.

$ curl -i \
    -H 'x-feather-args: feather' \
    -H 'x-feather-env: X=1 DEBUG=true' \
    -H 'x-feather-entrypoint: hello.py' \
    -d hello.py=@hello.py
HTTP/1.1 200 OK
Content-type: text/plain
x-feather-exit-status: 0
x-feather-time-taken: 0.1

sys.argv: ['feather']
Hello, feather!