# Τεκμηρίωση του Django - 6.0.7

# GeoDjango Installation

## Overview

In general, GeoDjango installation requires:

1. Python and Django

2. Spatial database

3. Geospatial libraries

Details for each of the requirements and installation instructions are provided in the sections below. In addition, platform-specific instructions are available for:

- macOS

- Windows

Use the Source

Because GeoDjango takes advantage of the latest in the open source geospatial software technology, recent versions of the libraries are necessary. If binary packages aren’t available for your platform, installation from source may be required. When compiling the libraries from source, please follow the directions closely, especially if you’re a beginner.

## Requirements

### Python and Django

Because GeoDjango is included with Django, please refer to Django’s installation instructions for details on how to install.

### Spatial database

PostgreSQL (with PostGIS), MySQL, Oracle, and SQLite (with SpatiaLite) are the spatial databases currently supported.

Σημείωση

PostGIS is recommended, because it is the most mature and feature-rich open source spatial database.

The geospatial libraries required for a GeoDjango installation depends on the spatial database used. The following lists the library requirements, supported versions, and any notes for each of the supported database backends:

Database | Library Requirements | Supported Versions | Notes
--- | --- | --- | ---
PostgreSQL | GEOS, GDAL, PROJ, PostGIS | 15+ | Requires PostGIS.
MySQL | GEOS, GDAL | 8.4+ | Limited functionality.
Oracle | GEOS, GDAL | 19+ | XE not supported.
SQLite | GEOS, GDAL, PROJ, SpatiaLite | 3.37.0+ | Requires SpatiaLite 4.3+

See also this comparison matrix on the OSGeo Wiki for PostgreSQL/PostGIS/GEOS/GDAL possible combinations.

## Installation

### Geospatial libraries

- Installing Geospatial libraries

### Database installation

- Installing PostGIS
- Installing SpatiaLite

### `DATABASES` configuration

Set the `ENGINE` setting to one of the spatial backends.

### Add `django.contrib.gis` to `INSTALLED_APPS`

Like other Django contrib applications, you will only need to add `django.contrib.gis` to `INSTALLED_APPS` in your settings. This is so that the `gis` templates can be located – if not done, then features such as the geographic admin or KML sitemaps will not function properly.

## Troubleshooting

If you can’t find the solution to your problem here then participate in the community! You can:

- Ask your question on the GeoDjango forum.

- File a ticket on the Django trac if you think there’s a bug. Make sure to provide a complete description of the problem, versions used, and specify the component as «GIS».

### Library environment settings

By far, the most common problem when installing GeoDjango is that the external shared libraries (e.g., for GEOS and GDAL) cannot be located. [1] Typically, the cause of this problem is that the operating system isn’t aware of the directory where the libraries built from source were installed.

In general, the library path may be set on a per-user basis by setting an environment variable, or by configuring the library path for the entire system.

#### `LD_LIBRARY_PATH` environment variable

A user may set this environment variable to customize the library paths they want to use. The typical library directory for software built from source is `/usr/local/lib`. Thus, `/usr/local/lib` needs to be included in the `LD_LIBRARY_PATH` variable. For example, the user could place the following in their bash profile:

    export LD_LIBRARY_PATH=/usr/local/lib

#### Setting system library path

On GNU/Linux systems, there is typically a file in `/etc/ld.so.conf`, which may include additional paths from files in another directory, such as `/etc/ld.so.conf.d`. As the root user, add the custom library path (like `/usr/local/lib`) on a new line in `ld.so.conf`. This is one example of how to do so:

    $ sudo echo /usr/local/lib >> /etc/ld.so.conf
    $ sudo ldconfig

For OpenSolaris users, the system library path may be modified using the `crle` utility. Run `crle` with no options to see the current configuration and use `crle -l` to set with the new library path. Be very careful when modifying the system library path:

    # crle -l $OLD_PATH:/usr/local/lib

#### Install `binutils`

GeoDjango uses the `find_library` function (from the `ctypes.util` Python module) to discover libraries. The `find_library` routine uses a program called `objdump` (part of the `binutils` package) to verify a shared library on GNU/Linux systems. Thus, if `binutils` is not installed on your Linux system then Python’s ctypes may not be able to find your library even if your library path is set correctly and geospatial libraries were built perfectly.

The `binutils` package may be installed on Debian and Ubuntu systems using the following command:

    $ sudo apt-get install binutils

Similarly, on Red Hat and CentOS systems:

    $ sudo yum install binutils

## Platform-specific instructions

### macOS

Because of the variety of packaging systems available for macOS, users have several different options for installing GeoDjango. These options are:

- Postgres.app (easiest and recommended)

- Homebrew

- Fink

- MacPorts

- Building from source

This section also includes instructions for installing an upgraded version of Python from packages provided by the Python Software Foundation, however, this is not required.

#### Python

Although macOS comes with Python installed, users can use framework installers provided by the Python Software Foundation. An advantage to using the installer is that macOS’s Python will remain «pristine» for internal operating system use.

Σημείωση

You will need to modify the `PATH` environment variable in your `.profile` file so that the new version of Python is used when `python` is entered at the command-line:

    export PATH=/Library/Frameworks/Python.framework/Versions/Current/bin:$PATH

#### Postgres.app

Postgres.app is a standalone PostgreSQL server that includes the PostGIS extension. You will also need to install `gdal` with Homebrew.

After installing Postgres.app, add the following to your `.bash_profile` so you can run the package’s programs from the command-line. Replace `X.Y` with the version of PostgreSQL in the Postgres.app you installed:

    export PATH=$PATH:/Applications/Postgres.app/Contents/Versions/X.Y/bin

You can check if the path is set up correctly by typing `which psql` at a terminal prompt.

#### Homebrew

Homebrew provides «recipes» for building binaries and packages from source. It provides recipes for the GeoDjango prerequisites on Macintosh computers running macOS. Because Homebrew still builds the software from source, Xcode is required.

Summary:

    $ brew install postgresql
    $ brew install postgis
    $ brew install gdal

##### Fink

Kurt Schwehr has been gracious enough to create GeoDjango packages for users of the Fink package system. Different packages are available (starting with `django-gis`), depending on which version of Python you want to use.

#### MacPorts

MacPorts may be used to install GeoDjango prerequisites on computers running macOS. Because MacPorts still builds the software from source, Xcode is required.

Summary:

    $ sudo port install postgresql15-server
    $ sudo port install geos
    $ sudo port install proj6
    $ sudo port install postgis3
    $ sudo port install gdal

Σημείωση

You will also have to modify the `PATH` in your `.profile` so that the MacPorts programs are accessible from the command-line:

    export PATH=/opt/local/bin:/opt/local/lib/postgresql15/bin

In addition, add the `DYLD_FALLBACK_LIBRARY_PATH` setting so that the libraries can be found by Python:

    export DYLD_FALLBACK_LIBRARY_PATH=/opt/local/lib:/opt/local/lib/postgresql15

### Windows

Proceed through the following sections sequentially in order to install GeoDjango on Windows. In this tutorial we will install 64 bit versions of each application.

#### Python

Install a 64 bit version of Python. See Install Python for further information.

#### PostgreSQL

Download the latest PostgreSQL 15.x installer from the EnterpriseDB website. After downloading, run the installer, follow the on-screen directions, and keep the default options unless you know the consequences of changing them.

Σημείωση

The PostgreSQL installer creates a new `postgres` database superuser You will be prompted once to set the password – make sure to remember it!

When the installer completes, it will ask to «Launch Stack Builder at exit?» – keep this checked, as it is necessary to install PostGIS.

Σημείωση

If installed successfully, the PostgreSQL server will run in the background each time the system is started as a Windows service. A PostgreSQL 15 start menu group will created and contains shortcuts for the Application Stack Builder (ASB) as well as the “SQL Shell”, which will launch a `psql` command window.

#### PostGIS

From within the Stack Builder (to run outside of the installer, Start ‣ PostgreSQL 15 ‣ Application Stack Builder), select PostgreSQL 15 (x64) on port 5432 from the drop down menu and click next. Expand the Categories ‣ Spatial Extensions menu tree and select PostGIS X.Y for PostgreSQL 15.

After clicking next, you will be prompted to confirm the selected package and «Download directory». Click next again, this will download PostGIS and you will be asked to click next to begin the PostGIS installer. Select the default options during install. The install process includes four Yes/No dialog boxes, the default option for all four is «No».

#### OSGeo4W

The OSGeo4W installer helps to install the PROJ, GDAL, and GEOS libraries required by GeoDjango. First, download the OSGeo4W installer, and run it. Select Express Web-GIS Install and click next. In the “Select Packages” list, ensure that GDAL is selected. If any other packages are enabled by default, they are not required by GeoDjango and may be unchecked safely. After clicking next and accepting the license agreements, the packages will be automatically downloaded and installed, after which you may exit the installer.

#### Modify Windows environment

In order to use GeoDjango, you will need to add your OSGeo4W directories to your Windows system `Path`, as well as create `GDAL_DATA` and `PROJ_LIB` environment variables. The following set of commands, executable with `cmd.exe`, will set this up. Restart your device once this is complete for new environment variables to be recognized:

    set OSGEO4W_ROOT=C:\OSGeo4W
    set GDAL_DATA=%OSGEO4W_ROOT%\apps\gdal\share\gdal
    set PROJ_LIB=%OSGEO4W_ROOT%\share\proj
    set PATH=%PATH%;%OSGEO4W_ROOT%\bin
    reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v Path /t REG_EXPAND_SZ /f /d "%PATH%"
    reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v GDAL_DATA /t REG_EXPAND_SZ /f /d "%GDAL_DATA%"
    reg ADD "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v PROJ_LIB /t REG_EXPAND_SZ /f /d "%PROJ_LIB%"

Σημείωση

Administrator privileges are required to execute these commands. To do this, run command prompt as administrator and enter the commands above. You need to log out and log back in again for the settings to take effect.

Σημείωση

If you customized the OSGeo4W installation directories, then you will need to modify the `OSGEO4W_ROOT` variables accordingly.

#### Install Django and set up database

Install Django on your system. It is recommended that you create a virtual environment for each project you create.

#### psycopg

The `psycopg` Python module provides the interface between Python and the PostgreSQL database. `psycopg` can be installed via pip within your Python virtual environment:

    ...\> py -m pip install psycopg

Footnotes

[1]

GeoDjango uses the `find_library()` routine from `ctypes.util` to locate shared libraries.