# Harakiri 腹切 (BETA)
[](https://travis-ci.org/elpulgardelpanda/harakiri)
[](https://hex.pm/packages/harakiri)
`Harakiri` was concieved to help applications kill themselves in response to a `touch` to a file on disk.
Given a list of _files_, an _application_, and an _action_. When any of the files change on disk (i.e. a gentle `touch` is enough), then the given action is fired over the app.
Everything is in an OTP Application so you can have it running in your
system to help all your other applications kill themselves.
Actions can be:
* `:stop`: Stops, unloads and deletes app's entry from path.
* `:reload`: like `:stop`, then adds given `lib_path` to path and runs
`Application.ensure_all_started/1`.
* `:restart`: Restarts the whole VM, runs `:init.restart`.
The `stop` and `reload` actions are suited for quick operations over a single application, not its dependencies. No other application is stopped and removed from path.
`reload` will ensure all dependencies are started before the app as it uses `ensure_all_started`, but it will not bother adding them to the path. So any dependency that changed will most probably not start because it will be missing from path.
The `restart` action is suited for a project deployed as the main application in the entire VM. `:init.restart` will kill all applications and then restart them all again.
## Use
Add to your `applications` list to ensure it's up before your app starts.
Then add to your `deps` like this:
```elixir
{:harakiri, ">= 0.4.0"}
```
Or if you feel brave enough:
```elixir
{:harakiri, github: "elpulgardelpanda/harakiri"}
```
Add an _action group_ like this:
```elixir
Harakiri.add %{paths: ["file1","file2"],
app: :myapp,
action: :stop}
```
That would only stop `:myapp`. To also reload it:
```elixir
Harakiri.add %{paths: ["file1","file2"],
app: :myapp,
action: :reload,
lib_path: "path"}
```
You are done. All given files (`file1`, `file2`, etc.) must exist. `lib_path` is the path to the folder containing the `ebin` folder for the current version of the app, usually a link to it. `lib_path` is only needed by `:reload`.
If your app is the main one in the Erlang node, then you may consider a whole `:restart`:
```elixir
Harakiri.add %{paths: ["/path/to/tmp/restart"],
app: :myapp,
action: :restart}
```
That would restart the VM. I.e. stop every application and start them again. All without stopping the running node, so it's fast enough for most cases. See [init.restart/0](http://www.erlang.org/doc/man/init.html#restart-0).
## Demo
[](https://asciinema.org/a/14617)
## TODOs
* Get it stable on production
* Optional creation of watched files.
* Support for multiple apps on each action set.
* Support for several actions on each action set.
* Support for multiple action sets on the same Harakiri process.
* More actions, or even support for funs.
* Deeper test, complete deploy/upgrade/reload simulation
## Changelog
### 0.4.0
* Use ETS to preserve state
* Rearrange using a supervised `Task` for the main loop and regular helpers to access the ETS table. No need for a `GenServer` anymore.
### 0.3.0
* Allow only one instance of the same action group.
### 0.2.0
* First release
