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# Config

Each application has its own environment.

`config/config.exs` is base of every project

config/dev.exs

```elixir
import_config "dev.secret.exs"
```

config/dev.secrets.exs

```elixir
use Mix.Config

config :sonar,
  google: "fasfdajkl"
```

#### Usage

```elixir
Application.fetch_env!(:sonar, :google)
Application.get_env(:sonar, :google, :default) #allows default and no error if key doesn't exist
```

### Based on env

```elixir
  if Mix.env() == :dev do
    #... can even be in router
  end
```

## Runtime.ex vs Prod.ex

Simply:

* `releases.exs` - runtime configuration for `release` **only**
* `#{Mix.env()}.exs` - i.e. `dev.exs`, `prod.exs`, `test.exs` - those are compiletime environment-specific configuration files
* `config.exs` - compiletime generic configuration file
* `releases.exs` - runtime generic configuration file


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