osm-watch

Advanced watching of OpenStreetMap changes

Features

Watching

Watch a bounding-box, get notified for changes that are truly within the bbox, not overlap
Watch an admin relation, get notified within
Watch a tag (within a bbox ?), get notified when
- NWR with the tag is modified
- Tag is added on a NWR
- Tag is removed from a NWR
- NWR with the tag is deleted
Watch an OSM user, get notified whenever he/she makes a commit

Notifications

Options:

Get notified only if first matching edit by a given contributor
Real-time / Scheduled
Generated RSS feed

Implementation

In order to provide the "tag is removed from a NWR" feature, it builds on the augmented diffs from overpass: http://overpass-api.de/augmented_diffs/

The OSC files are fetched, and processed:

The geometry of ways is reconstructed
The really deleted objects are identified and segregated
For modified objects, a previous/new version is created
Aggregated modifications are sent to the matchers

This backend is in Java, and is API only. A frontend TBD exists to set up the alerts

Third party code

OSM-Watch embeds some code from the JOSM project for the filtering part. The JOSM code is Copyright 2007 by Immanuel Scholz and others, Copyright 2008 by Petr Nejedly, and is used according to the terms of the GPL license