lunjon / blast

Load testing framework for HTTP APIs, powered by Elixir.

Blast

Load test framework, written in Elixir, that targets HTTP APIs.

It is currently only able to run from the command line, but I have plans to integrate it into a web-based interface built in Phoenix (inspired by Locust).

Installation

Script

If you have Elixir 1.15+ installed you can install blast as an escript:

$ mix do escript.build + escript.install

Nix

If you're using nix checkout the flake!

Running

As mentiod above, it is currently only supported running from your shell.

When started a simple non-interactive TUI will appear that renders the status of the application: requests per second, which requests are sent, etc.

However, to be able to start blast you need a spec file.

Spec file

The spec file defines which requests to send and is written in YAML. By default blast will lock for blast.y[a]ml in the current working directory, but you can point to another file with the --specfile option.

Example:

base-url: http://localhost:8080
requests:
  - path: "/test"
  - path: "/withbody"
    method: post
    body: "{\"test\": true}"
    headers:
      - name: content-type
        value: application/json

You can read more about it in the docs.

Hooks

Blast support hooks via external Elixir modules using the --hooks FILEPATH option.

This will load a filepath as an elixir file, expecting a single module that exports zero or more hooks.

You can read more about it in the docs.

Development

I recommend using the nix flake, like so:

$ nix develop # It takes a while the first time
...
$ mix deps.get # Fetch dependencies

Running as application

You can start blast using:

$ mix run --no-halt main.exs [ARGS]