pekko/akka-docs/rst/scala/http/common/timeouts.rst

.. _http-timeouts-scala:

Akka HTTP Timeouts
==================

Akka HTTP comes with a variety of built-in timeout mechanisms to protect your servers from malicious attacks or
programming mistakes. Some of these are simply configuration options (which may be overriden in code) while others
are left to the streaming APIs and are easily implementable as patterns in user-code directly.

Common timeouts
---------------

Idle timeouts
^^^^^^^^^^^^^

The ``idle-timeout`` is a global setting which sets the maximum inactivity time of a given connection.
In other words, if a connection is open but no request/response is being written to it for over ``idle-timeout`` time,
the connection will be automatically closed.

The setting works the same way for all connections, be it server-side or client-side, and it's configurable
independently for each of those using the following keys::

    akka.http.server.idle-timeout
    akka.http.client.idle-timeout
    akka.http.http-connection-pool.idle-timeout
    akka.http.http-connection-pool.client.idle-timeout

.. note::
  For the connection pooled client side the idle period is counted only when the pool has no pending requests waiting.


Server timeouts
---------------

.. _request-timeout-scala:

Request timeout
^^^^^^^^^^^^^^^

Request timeouts are a mechanism that limits the maximum time it may take to produce an ``HttpResponse`` from a route.
If that deadline is not met the server will automatically inject a Service Unavailable HTTP response and close the connection
to prevent it from leaking and staying around indefinitely (for example if by programming error a Future would never complete,
never sending the real response otherwise).

The default ``HttpResponse`` that is written when a request timeout is exceeded looks like this:

.. includecode2:: /../../akka-http-core/src/main/scala/akka/http/impl/engine/server/HttpServerBluePrint.scala
   :snippet: default-request-timeout-httpresponse

A default request timeout is applied globally to all routes and can be configured using the
``akka.http.server.request-timeout`` setting (which defaults to 20 seconds).

.. note::
  Please note that if multiple requests (``R1,R2,R3,...``) were sent by a client (see "HTTP pipelining")
  using the same connection and the ``n-th`` request triggers a request timeout the server will reply with an Http Response
  and close the connection, leaving the ``(n+1)-th`` (and subsequent requests on the same connection) unhandled.

The request timeout can be configured at run-time for a given route using the any of the :ref:`TimeoutDirectives`.

Bind timeout
^^^^^^^^^^^^

The bind timeout is the time period within which the TCP binding process must be completed (using any of the ``Http().bind*`` methods).
It can be configured using the ``akka.http.server.bind-timeout`` setting.

Client timeouts
---------------

Connecting timeout
^^^^^^^^^^^^^^^^^^

The connecting timeout is the time period within which the TCP connecting process must be completed.
Tweaking it should rarely be required, but it allows erroring out the connection in case a connection
is unable to be established for a given amount of time.

it can be configured using the ``akka.http.client.connecting-timeout`` setting.