standalone_servers.rst

How-to — Standalone Servers

Table of Contents

• Introduction
• Server Object
  • Run Server In Background

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Introduction

Standalone servers are classes that can create ready-to-run servers with no predefined asynchronous context (i.e., no :keyword:`async` / :keyword:`await`). They use (and block) a thread to accept requests, and their methods are meant to be used by other threads for control (e.g. shutdown).

By default, the runner is "asyncio", but it can be changed during object creation.

Server Object

.. tabs::

   .. group-tab:: StandaloneTCPNetworkServer

      .. literalinclude:: ../../_include/examples/howto/tcp_servers/standalone/server.py
         :linenos:
         :emphasize-lines: 10,21-26,46-50

   .. group-tab:: StandaloneUDPNetworkServer

      .. literalinclude:: ../../_include/examples/howto/udp_servers/standalone/server.py
         :linenos:
         :emphasize-lines: 10,21-26,46-50

Run Server In Background

Unlike asynchronous tasks, it is mandatory to spawn a separate execution thread. :class:`.NetworkServerThread` is useful for this case:

.. tabs::

   .. group-tab:: StandaloneTCPNetworkServer

      .. literalinclude:: ../../_include/examples/howto/tcp_servers/standalone/background_server.py
         :linenos:

   .. group-tab:: StandaloneUDPNetworkServer

      .. literalinclude:: ../../_include/examples/howto/udp_servers/standalone/background_server.py
         :linenos:

The output of the example should look something like this:

.. tabs::

   .. group-tab:: StandaloneTCPNetworkServer

      .. code:: console

         $ python background_server.py
         Server loop running in thread: Thread-1
         From server: {'thread': 'Thread-1', 'task': 'Task-6', 'request': {'message': 'Hello world 1'}}
         From server: {'thread': 'Thread-1', 'task': 'Task-8', 'request': {'message': 'Hello world 2'}}
         From server: {'thread': 'Thread-1', 'task': 'Task-10', 'request': {'message': 'Hello world 3'}}

   .. group-tab:: StandaloneUDPNetworkServer

      .. code:: console

         $ python background_server.py
         Server loop running in thread: Thread-1
         From server: {'thread': 'Thread-1', 'task': 'Task-5', 'request': {'message': 'Hello world 1'}}
         From server: {'thread': 'Thread-1', 'task': 'Task-6', 'request': {'message': 'Hello world 2'}}
         From server: {'thread': 'Thread-1', 'task': 'Task-7', 'request': {'message': 'Hello world 3'}}