QGIS embedded WMS/WFS/WCS asynchronous scalable server

Description

This is an asynchronous HTTP QGIS server written in python on top of the tornado framework and the 0MQ messaging framework for distributing requests workers.

It is based on the QGIS 3 server API for efficiently passing requests/responses using 0MQ messaging framework to workers.

The server may run as a self-contained single service or as a proxy server with an arbitrary number of workers running remotely or locally. Independent workers connect automatically to the front-end proxy with no need of special configuration on the proxy side. Thus, this is ideal for auto-scaling configuration for use with container orchestrator as Rancher, Swarm or Kubernetes.

The server is aimed at solving some real situations encountered in production environment: zero conf scalability, handle long-running request situation, auto restart...

Py-Qgis-server is constantly tested against QGIS release and ltr version. See the QGIS roadmap.

Features

• Multiples workers
• Fair queuing request dispatching
• Timeout for long-running/stalled requests
• Full support of qgis server plugins
• Auto-restart trigger for workers
• Support streamed/chunked responses
• SSL support
• Support for access control extensions
• Support for Qgis project stored in postgres database
• Support adding new projects cache handlers as python extension
• Preloading of Qgis projects in static cache
• WFS3 support
• Control exposition of Qgis API
• Management API (experimental)

Requirements:

• OS: Unix/Posix variants (Linux or OSX) (Windows not officially supported)
• Python >= 3.8
• Qgis >= 3.28
• Some python knowledge about python virtualenv and package installation.
• libzmq >= 4.0.1 and pyzmq >= 17

Documentation:

Latest documentation is available on docs.3liz.org

Installation

From Pypi

pip install py-qgis-server

From docker

Docker is the recommended way to deploy py-qgis-server as it ensure a working environment for running py-qgis-server

Follow the readme in the docker/ folder.

From source

Install in development mode

pip install -e .

Running the server

The server does not run as a daemon by itself, there are several ways to run a command as a daemon.

For example:

• Use Supervisor http://supervisord.org/. Will gives you full control over logs and server status notifications.
• Use the daemon command.
• Use systemd
• ...

Running the server

usage: qgisserver [-h] [-d] [-c [PATH]]
                  [--version] [-p PORT] [-b IP] [-w NUM] [-j NUM] [-u SETUID]
                  [--rootdir PATH] [--proxy] [--timeout SECONDS]

qgis/HTTP/0MQ scalable server

optional arguments:
  -h, --help            show this help message and exit
  -d, --debug           debug mode
  -c [PATH], --config [PATH]
                        Configuration file
  --version             Return version number and exit
  -p PORT, --port PORT  http port
  -b IP, --bind IP      Interface to bind to
  -w NUM, --workers NUM
                        Num workers
  -j NUM, --jobs NUM    Num server instances
  -u SETUID, --setuid SETUID
                        uid to switch to
  --rootdir PATH        Path to qgis projects
  --proxy               Run only as proxy
  --timeout SECONDS     Set client timeout in seconds

By default, the command will run server instances with workers and use unix sockets to communicate. This can be used to run the server as a single command.

Running proxy and workers separately

If the --proxy option the server will act as a proxy server to talk to independent qgis workers.

Qgis workers can be run using the command:

qgisserver-worker --host=localhost --rootdir=path/to/projects

Requests to OWS services

The OWS requests use the following format: /ows/?<ows_query_params>

Example:

http://myserver:8080/ows/?SERVICE=WFS&VERSION=1.1.0&REQUEST=GetCapabilities&MAP=<qgis_project_spec>

Requests to WFS3 OAPI

The requests use the following format: /wfs3/<wfs3_api_endpoint>?MAP=<qgis_project_spec>

Example:

http://myserver:8080/wfs3/collections.html?MAP=<qgis_project_spec>

Accessing the Qgis landing page and other qgis API

By default, the landing page is not enabled, see the documentation on how to enable the landing page.

Qgis api may be exposed on demand by configuring the api endpoints

Using with lizmap

In order to use the server with lizmap, you must set the following configuration in your lizmapConfig.ini.php:

[services]
wmsServerURL="http://my.domain:<port>/ows/"
...

; Use relative path
relativeWMSPath=true

Configuration

The configuration can be done either as configuration .ini file in or as environment variables.

The precedences of the configuration parameters is the following (from lowest to highest)

• Defaults values
• Environment variables
• Config file
• Command line options

Configuration parameters

Please look at the documentation for configuration options

Logging

By default, the server log on stdout/stderr and you have to configure redirection and log rotation on your infrastructure environment