README.md

LoggerLogstashBackend

About

A backend for the Elixir Logger that will send logs to the Logstash UDP input.

Supported options

• host: String.t. The hostname or ip address where to send the logs.
• port: Integer. The port number. Logstash should be listening with its UDP inputter.
• metadata: Keyword.t. Extra fields to be added when sending the logs. These will be merged with the metadata sent in every log message.
• level: Atom. Minimum level for this backend.
• type: String.t. Type of logs. Useful to filter in logstash.
• version: String.t. Version of logs. Useful to filter in logstash.

The host and port can be defined as environment variables as well using the {:system, "ENV_VAR_NAME"} convention

Sample Logstash config

input {
  udp {
    codec => json
    port => 10001
    queue_size => 10000
    workers => 10
    type => default_log_type
  }
}
output {
  stdout {}
  elasticsearch {
    protocol => http
  }
}

Using it with Mix

To use it in your Mix projects, first add it as a dependency:

def deps do
  [{:logger_logstash_backend, "~> 3.0.0"}]
end

Then run mix deps.get to install it.

Add logger as applications:

def application do
  [applications: [:logger]]
end

Configuration Examples

Runtime

Logger.add_backend {LoggerLogstashBackend, :debug}
Logger.configure {LoggerLogstashBackend, :debug},
  host: "127.0.0.1",
  port: 10001,
  level: :debug,
  metadata: ...

Application config

config :logger,
  backends: [{LoggerLogstashBackend, :error_log}, :console]

config :logger, :error_log,
  host: "some.host.com",
  port: 10001,
  level: :error,
  type: "my_type_of_app_or_node",
  version: "my_version_of_app_or_node",
  metadata: [
    extra_fields: "go here"
  ]

or

config :logger,
  backends: [{LoggerLogstashBackend, :error_log}, :console]

config :logger, :error_log,
  host: {:system, "LOGSTASH_BACKEND_HOST"},
  port: {:system, "LOGSTASH_BACKEND_PORT"},
  level: :error,
  type: "my_type_of_app_or_node",
  version: "my_version_of_app_or_node",
  metadata: [
    extra_fields: "go here"
  ]