Chaos Spawn
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## What and why

Inspired by netfix's chaos monkey. This library is intended to be a low level
process based equivalent. It works by replacing the ```Kernel.spawn```
functions with overidden ones that return processes that die at random. This should
force an app's supervision tree to actually work.

Currently super alpha. Probably not a good idea to use yet.

## Usage
Add Chaos Spawn as an application in your mix.exs:

def application do
  [applications: [:logger, :chaos_spawn]]

### Usage - in manual spawns
Use ```ChaosSpawn.Chaotic.Spawn``` in any module you wish to
have unreliable spawn calls. This will automatically replace the spawn calls
with the versions from the ```ChaosSpawn``` module.
``` elixir
defmodule ChaosSpawn.Example.Spawn do
  # Using the following will automatically replace all the spawn
  # functions with the chaotic ones.
  use ChaosSpawn.Chaotic.Spawn

  def test do
    spawn fn ->
      IO.puts "waiting for message"
      receive do
        _ -> IO.puts "message recieved!"

### Usage - in Gen servers
Instead of ```use```ing GenServer ```use``` the chaotic version and then
modify the start_link as below:  
defmodule ChaosSpawn.Example.GenServer do
  use ChaosSpawn.Chaotic.GenServer

  def start_link(opts \\ []) do
    # This function is imported when using ChaosSpawn.Chaotic.GenServer
    start_chaotic_link(__MODULE__, :ok, opts)
    # or to switch to the non chaotic version this is imported from GenServer:
    # start_link(__MODULE__, :ok, opts)

### Usage - in Gen events
Replace ```GenEvent.start_link``` with ```ChaosSpawn.Chaotic.GenEvent.start_link```.
{:ok, pid} = ChaosSpawn.Chaotic.GenEvent.start_link([])
GenEvent.add_handler(pid, SomeHandler, [])

### Config
Two keys are provided. The first ```kill_tick``` is the delay in milliseconds
that between chaos spawn checking for processes to kill.
```kill_probability``` is a float between 0 and
1 that determines the probability of a process being killed each tick.

config :chaos_spawn, :kill_tick, 1000
config :chaos_spawn, :kill_probability, 0.1

## Contributing
Contributions to this repo are more than welcome. Guidlines for succesfull PRs:
* Any large changes should ideally be opened as an issue first so a disucssion can be had.
* Code should be tested.
* Code under ```lib/``` should conform to coding standards tested by . You can test this by running ```mix dogma lib/```