Book Image

Python Geospatial Development - Third Edition

By : Erik Westra
Book Image

Python Geospatial Development - Third Edition

By: Erik Westra

Overview of this book

Geospatial development links your data to locations on the surface of the Earth. Writing geospatial programs involves tasks such as grouping data by location, storing and analyzing large amounts of spatial information, performing complex geospatial calculations, and drawing colorful interactive maps. In order to do this well, you’ll need appropriate tools and techniques, as well as a thorough understanding of geospatial concepts such as map projections, datums, and coordinate systems. This book provides an overview of the major geospatial concepts, data sources, and toolkits. It starts by showing you how to store and access spatial data using Python, how to perform a range of spatial calculations, and how to store spatial data in a database. Further on, the book teaches you how to build your own slippy map interface within a web application, and finishes with the detailed construction of a geospatial data editor using the GeoDjango framework. By the end of this book, you will be able to confidently use Python to write your own geospatial applications ranging from quick, one-off utilities to sophisticated web-based applications using maps and other geospatial data.
Table of Contents (20 chapters)
Python Geospatial Development Third Edition
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Setting up the ShapeEditor project


We now have to create the Django project for our ShapeEditor system. To do this, cd into the directory where you want the project's directory to be placed, and type the following:

% django-admin.py startproject shapeEditor

Tip

When you installed Django, it should have placed the django-admin.py program into your path, so you shouldn't need to tell the computer where this script resides.

All going well, Django will create a directory named shapeEditor with the following contents:

Now that the project has been created, we need to configure it. To do this, edit the settings.py file in the shapeEditor package directory. We need to tell our project how to access the database we set up, and we also want to enable the GeoDjango extension.

Start by searching for the DATABASES variable, and change it to look like the following:

DATABASES = {
    'default': {
        'ENGINE'   : 'django.contrib.gis.db.backends.postgis',
        'NAME'     : 'shapeeditor',
        'USER...