Logger Backends

https://hexdocs.pm/logger_backends/
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This module provides backends for Elixir's Logger with built-in overload protection, offering...
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### Initialize a backend

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Example of adding a backend which triggers the init/1 callback in the specified module.

```elixir
LoggerBackends.add(MyBackend)
```

--------------------------------

### Handle backend configuration

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Example of handling the :configure event to update backend state.

```elixir
{:configure, options}
```

```elixir
def handle_call({:configure, options}, state) do
  new_state = reconfigure_state(state, options)
  {:ok, :ok, new_state}
end
```

--------------------------------

### Add a backend

Source: https://hexdocs.pm/logger_backends/index.html

Adds a new backend and returns the supervisor start result.

```elixir
@spec add(
  backend(),
  keyword()
) :: Supervisor.on_start_child()
```

```elixir
LoggerBackends.add(MyBackend)
```

--------------------------------

### Configure Console Backend in config.exs

Source: https://hexdocs.pm/logger_backends/LoggerBackends.Console.html

Example configuration for the console logger backend within an Elixir project's configuration file.

```elixir
config :logger, LoggerBackends.Console,
  format: "\n$time $metadata[$level] $message\n",
  metadata: [:user_id]
```

--------------------------------

### Add a custom backend in Application.start/2

Source: https://hexdocs.pm/logger_backends/index.html

Register a custom backend during the application startup process.

```elixir
@impl true
def start(_type, _args) do
  LoggerBackends.add(MyCustomBackend)

  # ...
end
```

--------------------------------

### configure(options)

Source: https://hexdocs.pm/logger_backends/index.html

Applies runtime configuration to all backends.

```APIDOC
## configure(options)

### Description
Applies runtime configuration to all backends.

### Signature
`configure(options) :: :ok`
```

--------------------------------

### configure(options)

Source: https://hexdocs.pm/logger_backends/index.html

Applies runtime configuration to all backends.

```APIDOC
## configure(options)

### Description
Applies runtime configuration to all backends.

### Signature
`configure(options :: keyword()) :: :ok`
```

--------------------------------

### configure(options)

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Applies runtime configuration to all backends.

```APIDOC
## configure(options)

### Description
Applies runtime configuration to all backends.

### Parameters
- **options** (keyword()) - Required - The configuration options to apply to all backends.
```

--------------------------------

### configure(backend, options)

Source: https://hexdocs.pm/logger_backends/index.html

Configures a specific given backend.

```APIDOC
## configure(backend, options)

### Description
Configures a given backend.

### Signature
`configure(backend(), options) :: :ok | {:error, term()}`
```

--------------------------------

### configure(backend, options)

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Configures a specific backend.

```APIDOC
## configure(backend, options)

### Description
Applies runtime configuration to a specific backend.

### Parameters
- **backend** (backend()) - Required - The backend to configure.
- **options** (keyword()) - Required - The configuration options to apply.
```

--------------------------------

### configure(backend, options)

Source: https://hexdocs.pm/logger_backends/index.html

Configures a specific backend.

```APIDOC
## configure(backend, options)

### Description
Configures a given backend.

### Signature
`configure(backend :: backend(), options :: keyword()) :: term()`
```

--------------------------------

### Configure all backends

Source: https://hexdocs.pm/logger_backends/index.html

Applies runtime configuration to all registered backends.

```elixir
@spec configure(keyword()) :: :ok
```

--------------------------------

### add(backend, opts \ [])

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Adds a new backend to the logger system. This function triggers the init/1 callback of the specified backend.

```APIDOC
## add(backend, opts \ [])

### Description
Adds a new backend to the logger system. Adding a backend calls the init/1 function in that backend with the name of the backend as its argument.

### Parameters
- **backend** (backend()) - Required - The logger handler to add.
- **opts** (keyword()) - Optional - Configuration options. Supported option: :flush (when true, guarantees all messages currently sent to Logger are processed before the backend is added).

### Returns
- **{:ok, pid}** - Returned if the backend's init/1 callback returns {:ok, _} or {:error, :ignore}.
- **{:error, {reason, info}}** - Returned if the handler returns {:error, reason} from init/1.
```

--------------------------------

### Configure a custom backend

Source: https://hexdocs.pm/logger_backends/index.html

Define configuration parameters for a custom backend within the application's configuration files.

```elixir
config :logger, MyCustomBackend,
  some_config: ...
```

--------------------------------

### Configure a specific backend

Source: https://hexdocs.pm/logger_backends/index.html

Applies configuration settings to a single specified backend.

```elixir
@spec configure(
  backend(),
  keyword()
) :: term()
```

--------------------------------

### Handle backend configuration calls

Source: https://hexdocs.pm/logger_backends/index.html

Implement this handle_call clause to process configuration updates sent via configure_backend/2.

```elixir
def handle_call({:configure, options}, state) do
  new_state = reconfigure_state(state, options)
  {:ok, :ok, new_state}
end
```

--------------------------------

### build(event)

Source: https://hexdocs.pm/logger_backends_json/Logger.Backends.JSON.Event.html

Transforms a log event into a map structure suitable for JSON output.

```APIDOC
## build(event)

### Description
Builds a map from the provided event message, which is subsequently used as input for JSON serialization.

### Parameters
- **event** (struct) - Required - A Logger.Backends.JSON.Event struct.

### Returns
- **map** - A map representation of the log event.
```

--------------------------------

### Define backend type

Source: https://hexdocs.pm/logger_backends/index.html

Represents a logger handler as a gen_event handler.

```elixir
@type backend() :: :gen_event.handler()
```

--------------------------------

### LoggerBackends.Console Configuration

Source: https://hexdocs.pm/logger_backends/LoggerBackends.Console.html

Configuration options for the LoggerBackends.Console backend in an Elixir application.

```APIDOC
## Configuration Options

### Description
The `LoggerBackends.Console` backend can be configured in your `config/config.exs` file to customize how logs are printed to the console.

### Options
- **:level** (atom) - The minimum level to be logged by this backend.
- **:format** (string | {module, function}) - The format message used to print logs. Defaults to: `"\n$time $metadata[$level] $message\n"`.
- **:metadata** (list | :all) - The metadata to be printed. Defaults to an empty list.
- **:colors** (keyword list) - Coloring options for different log levels.
- **:device** (atom) - The device to log messages to. Defaults to `:user`.
- **:max_buffer** (integer) - Maximum events to buffer while waiting for IO confirmation. Defaults to 32.

### Example
```elixir
config :logger, LoggerBackends.Console,
  format: "\n$time $metadata[$level] $message\n",
  metadata: [:user_id]
```
```

--------------------------------

### Add a backend

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Adds a new backend and specifies the return type for the operation.

```elixir
@spec add(
  backend(),
  keyword()
) :: Supervisor.on_start_child()
```

--------------------------------

### remove(backend, opts)

Source: https://hexdocs.pm/logger_backends/index.html

Removes a backend with optional flush configuration.

```APIDOC
## remove(backend, opts \\ [])

### Description
Removes a backend.

### Signature
`remove(backend :: backend(), opts :: keyword()) :: :ok | {:error, term()}

### Parameters
- **flush** (boolean) - Optional - When true, guarantees all messages currently sent to Logger are processed before the backend is removed.
```

--------------------------------

### remove(backend, opts \ [])

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Removes a backend from the logger system.

```APIDOC
## remove(backend, opts \ [])

### Description
Removes a backend from the logger system.

### Parameters
- **backend** (backend()) - Required - The backend to remove.
- **opts** (keyword()) - Optional - Configuration options.
```

--------------------------------

### remove(backend, opts \ [])

Source: https://hexdocs.pm/logger_backends/index.html

Removes a specified backend.

```APIDOC
## remove(backend, opts \ [])

### Description
Removes a backend.

### Signature
`remove(backend(), keyword()) :: :ok | {:error, term()}`
```

--------------------------------

### allow?(event)

Source: https://hexdocs.pm/logger_backends_json/Logger.Backends.JSON.Event.html

Determines whether a log event should be processed based on custom logic.

```APIDOC
## allow?(event)

### Description
Decides whether to proceed with evaluating the log entry. This acts as an additional layer of filtering beyond the standard log level configuration.

### Parameters
- **event** (struct) - Required - A Logger.Backends.JSON.Event struct.

### Returns
- **boolean** - Returns true if the event should be processed, false otherwise.
```

--------------------------------

### Remove a backend

Source: https://hexdocs.pm/logger_backends/index.html

Removes a backend from the logger. Use the :flush option to ensure pending messages are processed before removal.

```elixir
@spec remove(
  backend(),
  keyword()
) :: :ok | {:error, term()}
```

--------------------------------

### remove(backend, opts)

Source: https://hexdocs.pm/logger_backends/LoggerBackends.html

Removes a specified backend from the logger.

```APIDOC
## remove(backend, opts \\ [])

### Description
Removes a backend.

### Signature
`remove(backend :: backend(), opts :: keyword()) :: :ok | {:error, term()}

### Parameters
- **backend** (backend()) - Required - The backend to remove.
- **opts** (keyword()) - Optional - Options for removal.
  - **flush** (boolean) - When true, guarantees all messages currently sent to Logger are processed before the backend is removed.
```

--------------------------------

### encode(object)

Source: https://hexdocs.pm/logger_backends_json/Logger.Backends.JSON.DummyEncoder.html

Encodes a given object into a JSON format suitable for logging.

```APIDOC
## encode(object)

### Description
Encodes the provided object into a JSON representation for use in logging backends.

### Parameters
- **object** (any) - Required - The data structure to be encoded into JSON.
```

--------------------------------

### Ignore remote group leader events in custom backend

Source: https://hexdocs.pm/logger_backends/index.html

Use this pattern in handle_event to filter out messages originating from different nodes.

```elixir
def handle_event({_level, gl, {Logger, _, _, _}}, state)
    when node(gl) != node() do
  {:ok, state}
end
```
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