The goal for this lesson: To learn how to install QGIS Server on Debian Stretch. With negligible variations (prepending sudo to all admin commands) you can also follow it for any Debian based distribution like Ubuntu and its derivatives.
In this lesson we’re going to do only the install from packages as shown here .
First add the QGIS repository by creating the /etc/apt/sources.list.d/debian-qgis.list file with the following content:
# latest stable
deb http://qgis.org/debian stretch main
deb-src http://qgis.org/debian stretch main
After you add the qgis.org repository public key to your apt keyring (follow the above link on how to do it) you can run the apt-get update command to refresh the packages list and apt-get dist-upgrade to upgrade the packages.
Catatan
Currently Debian stable has LTR qgis packages in the source jessie-backports, so the above steps are not necessary. Just add the jessie-backports repository and install with the -t jessie-backports option.
Install QGIS Server with:
apt-get install qgis-server python-qgis
Catatan
adding -y at the end of the apt-get command will run it straight away, without requiring confirmation.
QGIS Server should be used in production without QGIS Desktop (with the accompagning X Server) installed on the same machine.
The QGIS Server executable is qgis_mapserv.fcgi. You can check where it has been installed by running find / -name 'qgis_mapserv.fcgi' which should output something like /usr/lib/cgi-bin/qgis_mapserv.fcgi.
Optionally, if you want to do a command line test at this time you can run the /usr/lib/cgi-bin/qgis_mapserv.fcgi command which should output something like:
QFSFileEngine::open: No file name specified
Warning 1: Unable to find driver ECW to unload from GDAL_SKIP environment variable.
Warning 1: Unable to find driver ECW to unload from GDAL_SKIP environment variable.
Warning 1: Unable to find driver JP2ECW to unload from GDAL_SKIP environment variable.
Warning 1: Unable to find driver ECW to unload from GDAL_SKIP environment variable.
Warning 1: Unable to find driver JP2ECW to unload from GDAL_SKIP environment variable.
Content-Length: 206
Content-Type: text/xml; charset=utf-8
<ServiceExceptionReport version="1.3.0" xmlns="http://www.opengis.net/ogc">
<ServiceException code="Service configuration error">Service unknown or unsupported</ServiceException>
</ServiceExceptionReport>
This is a good thing, it tells you we’re on the right track as the server is saying that we haven’t asked for a supported service. We’ll see later on how to make WMS requests.
In order to access on the installed QGIS server from an Internet Browser we need to use an HTTP server.
In this lesson we’re going to use the Apache HTTP server, colloquially called Apache.
First we need to install Apache by running the following command in a terminal: apt-get install apache2 libapache2-mod-fcgid.
In the /etc/apache2/sites-available directory let’s create a file called qgis.demo.conf, with this content:
<VirtualHost *:80>
ServerAdmin webmaster@localhost
ServerName qgis.demo
DocumentRoot /var/www/html
# Apache logs (different than QGIS Server log)
ErrorLog ${APACHE_LOG_DIR}/qgis.demo.error.log
CustomLog ${APACHE_LOG_DIR}/qgis.demo.access.log combined
# Longer timeout for WPS... default = 40
FcgidIOTimeout 120
FcgidInitialEnv LC_ALL "en_US.UTF-8"
FcgidInitialEnv PYTHONIOENCODING UTF-8
FcgidInitialEnv LANG "en_US.UTF-8"
# QGIS log (different from apache logs) see http://docs.qgis.org/testing/en/docs/user_manual/working_with_ogc/ogc_server_support.html#qgis-server-logging
FcgidInitialEnv QGIS_SERVER_LOG_FILE /var/log/qgis/qgisserver.log
FcgidInitialEnv QGIS_SERVER_LOG_LEVEL 0
FcgidInitialEnv QGIS_DEBUG 1
# default QGIS project
SetEnv QGIS_PROJECT_FILE /home/qgis/projects/world.qgs
# QGIS_AUTH_DB_DIR_PATH must lead to a directory writeable by the Server's FCGI process user
FcgidInitialEnv QGIS_AUTH_DB_DIR_PATH "/home/qgis/qgisserverdb/"
FcgidInitialEnv QGIS_AUTH_PASSWORD_FILE "/home/qgis/qgisserverdb/qgis-auth.db"
# See http://docs.qgis.org/testing/en/docs/user_manual/working_with_vector/supported_data.html#pg-service-file
SetEnv PGSERVICEFILE /home/qgis/.pg_service.conf
FcgidInitialEnv PGPASSFILE "/home/qgis/.pgpass"
# Tell QGIS Server instances to use a specific display number
FcgidInitialEnv DISPLAY ":99"
# if qgis-server is installed from packages in debian based distros this is usually /usr/lib/cgi-bin/
# run "locate qgis_mapserv.fcgi" if you don't know where qgis_mapserv.fcgi is
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
<Directory "/usr/lib/cgi-bin/">
AllowOverride None
Options +ExecCGI -MultiViews -SymLinksIfOwnerMatch
Order allow,deny
Allow from all
Require all granted
</Directory>
<IfModule mod_fcgid.c>
FcgidMaxRequestLen 26214400
FcgidConnectTimeout 60
</IfModule>
</VirtualHost>
You can do the above in a linux Desktop system by pasting and saving the above configuration after doing sudo nano /etc/apache2/sites-available/qgis.demo.conf.
Catatan
See some of the configuration options are explained in the Server Advanced configuration section.
Let’s now create the directories that will store the QGIS Server logs and the authentication database:
sudo mkdir /var/log/qgis/
sudo chown www-data:www-data /var/log/qgis
mkdir /home/qgis/qgisserverdb
sudo chown www-data:www-data /home/qgis/qgisserverdb
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www-data is the Apache user on Debian based systems and we need Apache to have access to those locations or files. The chown www-data... commands changes the owner of the respective directories and files to www-data.
We can now enable the virtual host, enable the fcgid mod if it’s not already enabled and restart the apache2 service:
sudo a2enmod fcgid
sudo a2ensite qgis.demo
sudo service apache2 restart
Catatan
If you installed QGIS Server without running an X Server (included in Linux Desktop) and if you also want to use the GetPrint command then you should install a fake X Server and tell QGIS Server to use it. You can do that by running the following commands.
Install xvfb:
sudo apt-get install xvfb
Create the service file:
sudo sh -c \
"echo \
'[Unit]
Description=X Virtual Frame Buffer Service
After=network.target
[Service]
ExecStart=/usr/bin/Xvfb :99 -screen 0 1024x768x24 -ac +extension GLX +render -noreset
[Install]
WantedBy=multi-user.target' \
> /etc/systemd/system/xvfb.service"
Enable, start and check the status of the xvfb.service:
sudo systemctl enable xvfb.service
sudo systemctl start xvfb.service
sudo systemctl status xvfb.service
In the above configuration file there’s a FcgidInitialEnv DISPLAY ":99" that tells QGIS Server instances to use display no. 99. If you’re running the Server in Desktop then there’s no need to install xvfb and you should simply comment with # this specific setting in the configuration file. More info at http://www.itopen.it/qgis-server-setup-notes/.
Now that Apache knows that he should answer requests to http://qgis.demo we also need to setup the client system so that it knows who qgis.demo is. We do that by adding 127.0.0.1 qgis.demo in the hosts file. We can do it with sudo sh -c "echo '127.0.0.1 qgis.demo' >> /etc/hosts". Replace 127.0.0.1 with the IP of your server.
Catatan
Remember that both the myhost.conf and /etc/hosts files should be configured for our setup to work. You can also test the access to your QGIS Server from other clients on the network (e.g. Windows or Macos machines) by going to their /etc/hosts file and point the myhost name to whatever IP the server machine has on the network. You can be sure that that specific IP is not 127.0.0.1 as that’s the local IP, only accessible from the local machine. On *nix machines the hosts file is located in /etc, while on Windows it’s under the C:\Windows\System32\drivers\etc directory. Under Windows you need to start your text editor with administrator privileges before opening the hosts file.
We can test one of the installed qgis servers with a http request from command line with curl http://qgis.demo/cgi-bin/qgis_mapserv.fcgi which should output:
<ServiceExceptionReport version="1.3.0" xmlns="http://www.opengis.net/ogc">
<ServiceException code="Service configuration error">Service unknown or unsupported</ServiceException>
</ServiceExceptionReport>
Catatan
curl can be installed with sudo apt-get install curl.
Apache is now configured.
Let’s create another Apache virtual host pointing to QGIS Server. You can choose whatever name you like (coco.bango, super.duper.training, example.com, etc.) but for simplicity sake we’re going to use myhost.
qgis@qgis:~$ ping myhost
PING myhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.024 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.029 ms
..
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>404 Not Found</title>
</head><body>
<h1>Not Found</h1>
<p>The requested URL /cgi-bin/qgis_mapserv.fcgi was not found on this server.</p>
<hr>
<address>Apache/2.4.25 (Debian) Server at myhost Port 80</address>
</body></html>
You learned how to install different QGIS Server versions from packages, how to configure Apache with QGIS Server, on Debian based Linux distros.
Now that you’ve installed QGIS Server and it’s accesible through the HTTP protocol, we need to learn how to access some of the services it can offer. The topic of the next lesson is to learn how to access QGIS Server WMS services.