Knowhere

A zgeo.* demo application using Grok

The paleolithic geographer isn't concerned about fancy geographic information systems. He wants a know-where-things-are system; hence the name of this demo app: Knowhere (pronounced "Oog"). Knowhere annotates resources with geographic location metadata and publishes them using GeoRSS (Atom, specifically) or KML so that a even a caveman can visualize them in the context of other geographic information on the Web.

Example

http://zcologia.com/kw/demo

See also http://zcologia.com/kw/demo/@@kml-document (KML document, in Google Maps) and http://zcologia.com/kw/demo/@@atom-search-feed (Atom feed with GeoRSS and some OpenSearch? extensions).

Getting Started

Building and launching Knowhere is a 5 step process that requires Python 2.4, gmake, gcc, etc. Within 15 minutes you can be publishing geo-referenced content.

Start by getting the code from its public Mercurial repository, http://zcologia.com/sgillies/hg/knowhere: 

$ hg clone http://zcologia.com/sgillies/hg/knowhere my-knowhere

or by downloading and extracting the archive attached to this page: knowhere-0.4.2.tar.gz

Change into that new directory, make it a virtual environment, get Cython, bootstrap the project, and build it out: 

$ cd my-knowhere
$ virtualenv .
$ source bin/activate
(my-knowhere)$ ./bin/easy_install Cython
(my-knowhere)$ ./bin/python bootstrap.py
(my-knowhere)$ ./bin/buildout

This downloads and builds 2 C/C++ libraries (GEOS and spatialindex), and fetches a heap of eggs. It will take a few minutes.

When the build out is complete, edit 2 configuration files. In parts/zopectl/zope.conf, set the port number to an open value. In parts/app/site.zcml, change the management password from "admin" to one less obvious. That done, start up the application: 

$ ./setenv
$ ./bin/zopectl fg

Browse to http://localhost:8080 (let's presume that's where it's at), authenticate, and you should see a Grok management page like this:

Add a new application named "cities" as shown. Afterwards, the first thing to do is to add a spatial catalog to the cities application by using the http://localhost:8080/cities/@@create-spatialcatalog view. Then return to http://localhost:8080/cities and add a new placemark using the form at the bottom. Try field values like these

  • name: fort-collins
  • title: Fort Collins
  • description: Fort Collins, Colorado, USA
  • text: The little geospatial hothouse on the prairie
  • geometry type: Point
  • coordinates: [-105.08, 40.59]

using a GeoJSON coordinate representation, and submit.

The Map

The more fun way to create new placemarks is through the http://localhost:8080/cities/map view. Select the 3rd tool from the left (pencil) in the toolbar, and click in the map to create a placemark geometry in the map buffer. Should display then in green. Next, fill out the fields on the right and submit.

AtomPub?

You can also post Atom entries (content-type: application/atom+xml;type=entry) to http://http://localhost:8080/cities/atompub-collection. The Ajax map uses this API.

KML for Google Maps/Earth

The zgeo.kml package provides KML representations of containers of georeferenceable objects. Browse to http://localhost:8080/cities/@@kml-document for an example.

The zgeo.atom package provides Atom entry and feed document views with GeoRSS. For examples, browse to http://localhost:8080/cities/fort-collins/atom-entry and http://localhost:8080/cities/atompub-collection.

Browse source

[Tickets]

Credits

Sean Gillies (for Pleiades)

OSX testing: Howard Butler, Kai Lautaportti

Pleiades is an international research network and associated web portal and content management system devoted to the study of ancient geography.

See http://icon.stoa.org/trac/pleiades/wiki.

Funding for the creation of this software was provided by a grant from the U.S. National Endowment for the Humanities (http://www.neh.gov).

Attachments