LoggerTelegramBackend

A logger backend for Telegram.

Installation

Add :logger_telegram_backend, :logger_backends and :finch to your list of dependencies in mix.exs:

def deps do
  [
    {:logger_telegram_backend, "~> 3.0-rc"},
    {:logger_backends, "~> 1.0"},
    {:finch, "~> 1.18"},
  ]
end

In your Application.start/2 callback, add the LoggerTelegramBackend backend:

@impl true
def start(_type, _args) do
  LoggerBackends.add(LoggerTelegramBackend)

  # ...
end

Configuration

First you need to create a Telegram Bot. Follow the instructions here to create one and get the token for the bot. You will need to send a message first as bots are not allowed to contact users. Then retrieve your chat_id with $ curl -X GET https://api.telegram.org/botYOUR_TOKEN/getUpdates.

Then configure the telegram chat_id and bot token:

config :logger, LoggerTelegramBackend,
  chat_id: "$chatId",
  token: "$botToken"

Options

The available options are:

• :level - the level to be logged by this backend (either :debug, :info, :warning or :error).

  Note that messages are first filtered by the general :level configuration for the :logger application.

  Default: nil (all levels are logged)

• :metadata - the metadata to be included in the message. Setting :metadata to :all will get all metadata. Default: [:line, :function, :module, :application, :file].

• :metadata_filter - the metadata which is required in order for a message to be logged.

  Default: nil

• :client - If you need different functionality for the HTTP client, you can define your own module that implements the LoggerTelegramBackend.HTTPClient behaviour and set client to that module.

  By default, selects the first client in the list whose application is loaded:

  • LoggerTelegramBackend.HTTPClient.Finch (requires :finch)
  • LoggerTelegramBackend.HTTPClient.Hackney (requires:hackney)

• :client_pool_opts - The options passed to configure the pool.

  See Finch or Hackney.

  Default: []

• :client_request_opts - The options passed on every request.

  See Finch or Hackney.

  Default: []

Examples

Custom HTTP client

1. Add a module that implements the LoggerTelegramBackend.HTTPClient behaviour

2. Pass your client module to the :client option:

   config :logger, LoggerTelegramBackend,
     client: MyClient,
     # ...
   

Metadata filter

config :logger, LoggerTelegramBackend,
  chat_id: "$chatId",
  token: "$botToken",
  level: :info,
  metadata: :all,
  metadata_filter: [application: :ui]

SOCKS5 proxy

config :logger, LoggerTelegramBackend,
  chat_id: "$chatId",
  token: "$botToken",
  client: LoggerTelegramBackend.HTTPClient.Hackney,
  client_request_opts: [
    proxy: {:socks5, ~c"127.0.0.1", 9050}
  ]

See the hackney docs for further information.