Phoenix.Logger (Phoenix v1.6.2) View Source
Instrumenter to handle logging of various instrumentation events.
Instrumentation
Phoenix uses the :telemetry
library for instrumentation. The following events
are published by Phoenix with the following measurements and metadata:
[:phoenix, :endpoint, :start]
- dispatched byPlug.Telemetry
in your endpoint, usually after code reloading- Measurement:
%{system_time: system_time}
- Metadata:
%{conn: Plug.Conn.t, options: Keyword.t}
- Options:
%{log: Logger.level | false}
- Disable logging: In your endpoint
plug Plug.Telemetry, ..., log: Logger.level | false
- Configure log level dynamically:
plug Plug.Telemetry, ..., log: {Mod, Fun, Args}
- Measurement:
[:phoenix, :endpoint, :stop]
- dispatched byPlug.Telemetry
in your endpoint whenever the response is sent- Measurement:
%{duration: native_time}
- Metadata:
%{conn: Plug.Conn.t, options: Keyword.t}
- Options:
%{log: Logger.level | false}
- Disable logging: In your endpoint
plug Plug.Telemetry, ..., log: Logger.level | false
- Configure log level dynamically:
plug Plug.Telemetry, ..., log: {Mod, Fun, Args}
- Measurement:
[:phoenix, :router_dispatch, :start]
- dispatched byPhoenix.Router
before dispatching to a matched route- Measurement:
%{system_time: System.system_time}
- Metadata:
%{conn: Plug.Conn.t, route: binary, plug: module, plug_opts: term, path_params: map, pipe_through: [atom], log: Logger.level | false}
- Disable logging: Pass
log: false
to the router macro, for example:get("/page", PageController, :index, log: false)
- Configure log level dynamically:
get("/page", PageController, :index, log: {Mod, Fun, Args}
- Measurement:
[:phoenix, :router_dispatch, :exception]
- dispatched byPhoenix.Router
after exceptions on dispatching a route- Measurement:
%{duration: native_time}
- Metadata:
%{conn: Plug.Conn.t, kind: :throw | :error | :exit, reason: term(), stacktrace: Exception.stacktrace()}
- Disable logging: This event is not logged
- Measurement:
[:phoenix, :router_dispatch, :stop]
- dispatched byPhoenix.Router
after successfully dispatching a matched route- Measurement:
%{duration: native_time}
- Metadata:
%{conn: Plug.Conn.t, route: binary, plug: module, plug_opts: term, path_params: map, pipe_through: [atom], log: Logger.level | false}
- Disable logging: This event is not logged
- Measurement:
[:phoenix, :error_rendered]
- dispatched at the end of an error view being rendered- Measurement:
%{duration: native_time}
- Metadata:
%{conn: Plug.Conn.t, status: Plug.Conn.status, kind: Exception.kind, reason: term, stacktrace: Exception.stacktrace}
- Disable logging: Set
render_errors: [log: false]
on your endpoint configuration
- Measurement:
[:phoenix, :socket_connected]
- dispatched byPhoenix.Socket
, at the end of a socket connection- Measurement:
%{duration: native_time}
- Metadata:
%{endpoint: atom, transport: atom, params: term, connect_info: map, vsn: binary, user_socket: atom, result: :ok | :error, serializer: atom, log: Logger.level | false}
- Disable logging:
use Phoenix.Socket, log: false
orsocket "/foo", MySocket, websocket: [log: false]
in your endpoint
- Measurement:
[:phoenix, :channel_joined]
- dispatched at the end of a channel join- Measurement:
%{duration: native_time}
- Metadata:
%{result: :ok | :error, params: term, socket: Phoenix.Socket.t}
- Disable logging: This event cannot be disabled
- Measurement:
[:phoenix, :channel_handled_in]
- dispatched at the end of a channel handle in- Measurement:
%{duration: native_time}
- Metadata:
%{event: binary, params: term, socket: Phoenix.Socket.t}
- Disable logging: This event cannot be disabled
- Measurement:
To see an example of how Phoenix LiveDashboard uses these events to create metrics, visit https://hexdocs.pm/phoenix_live_dashboard/metrics.html.
Parameter filtering
When logging parameters, Phoenix can filter out sensitive parameters
such as passwords and tokens. Parameters to be filtered can be
added via the :filter_parameters
option:
config :phoenix, :filter_parameters, ["password", "secret"]
With the configuration above, Phoenix will filter any parameter
that contains the terms password
or secret
. The match is
case sensitive.
Phoenix's default is ["password"]
.
Phoenix can filter all parameters by default and selectively keep parameters. This can be configured like so:
config :phoenix, :filter_parameters, {:keep, ["id", "order"]}
With the configuration above, Phoenix will filter all parameters,
except those that match exactly id
or order
. If a kept parameter
matches, all parameters nested under that one will also be kept.
Dynamic log level
In some cases you may wish to set the log level dynamically
on a per-request basis. To do so, set the :log
option to
a tuple, {Mod, Fun, Args}
. The Plug.Conn.t()
for the
request will be prepended to the provided list of arguments.
When invoked, your function must return a
Logger.level()
or false
to
disable logging for the request.
For example, in your Endpoint you might do something like this:
# lib/my_app_web/endpoint.ex
plug Plug.Telemetry,
event_prefix: [:phoenix, :endpoint],
log: {__MODULE__, :log_level, []}
# Disables logging for routes like /status/*
def log_level(%{path_info: ["status" | _]}), do: false
def log_level(_), do: :info
Disabling
When you are using custom logging system it is not always desirable to enable
Phoenix.Logger
by default. You can always disable this in general by:
config :phoenix, :logger, false