Add docs on how to compile on Debian 12 (#309)

* Copy the Ubuntu 20.04 docs to Debian 12

* Update debian docs to refer to proper location of example map

* update debian docs to match what mapnik installs

* Update debian docs to match the installed URL

* Link to debian docs in README

Author: amandasaurus

README.rst

@@ -61,6 +61,7 @@ distributions:
 * `CentOS 7 <docs/build/building_on_centos_7.md>`__
 * `Fedora 34 </docs/build/building_on_fedora_34.md>`__
 * `Ubuntu 20.04 </docs/build/building_on_ubuntu_20_04.md>`__ (this should work as well for Debian 10)
+* `Debian 12 </docs/build/building_on_debian_12.md>`__
 
 Configuration
 -------------

docs/build/building_on_debian_12.md

@@ -0,0 +1,68 @@
+# Building on Debian 12
+
+This documents step by step on how to compile and put into use the software `mod_tile` and `renderd`.
+Please see our [Continuous Integration script](../../.github/workflows/build-and-test.yml) for more detail.
+
+```shell
+#!/usr/bin/env bash
+
+# Update installed packages
+sudo apt update && sudo apt upgrade --yes
+
+# Install build dependencies
+# (the last two are optional)
+sudo apt install build-essential \
+  autoconf \
+  apache2-dev \
+  libcairo2-dev \
+  libcurl4-gnutls-dev \
+  libglib2.0-dev \
+  libiniparser-dev \
+  libmapnik-dev \
+  libmemcached-dev \
+  librados-dev
+
+# Download, build & install
+git clone https://github.com/openstreetmap/mod_tile.git /usr/local/src/mod_tile
+cd /usr/local/src/mod_tile
+./autogen.sh
+./configure
+make
+
+# Create tiles directory
+sudo mkdir --parents /run/renderd /var/cache/renderd/tiles
+
+# Move files of example map
+sudo mkdir --parents /usr/share/renderd/
+sudo cp -r "utils/example-map" /usr/share/renderd/example-map
+
+# Link leaflet library
+sudo ln --symbolic \
+  /usr/share/javascript/leaflet \
+  /usr/share/renderd/example-map/leaflet
+
+# Add configuration
+sudo cp "etc/renderd/renderd.conf.examples" /etc/renderd.conf
+sudo cp "etc/apache2/renderd.conf" /etc/apach2/conf.d/renderd.conf
+sudo cp "etc/apache2/renderd-example-map.conf" \
+  /etc/apache2/conf-enabled/renderd-example-map.conf
+
+# Apply Debian specific changes to configuration files
+sudo sed --in-place \
+  "s#/usr/lib/mapnik/3.0/input#/usr/lib/mapnik/3.1/input#g" \
+  /etc/renderd.conf
+
+# Add and activate mod_tile for Apache
+echo "LoadModule tile_module /usr/lib/apache2/modules/mod_tile.so" \
+  | sudo tee --append /etc/apache2/mods-enabled/mod_tile.load
+
+# Install software
+sudo make install
+sudo make install-mod_tile
+
+# Start services
+sudo systemctl --now enable apache2
+sudo renderd -f
+```
+
+Then you can visit: `http://localhost:8081/renderd-example-map`