Testing changes before upload
Before you upload a changeset, you may wish to test it in one or more applications that use OpenStreetMap data to ensure that your changes have the effect you intended. Many OpenStreetMap-based applications have ways that you can load custom data for this purpose, though the procedures vary widely in difficulty. There's no general expectation that contributors do such testing. But testing your own change while you have it fresh in your mind can sometimes be the most efficient way to detect and fix any problems, compared to uploading, waiting for the main instances of OpenStreetMap-based applications to update their map data to include your changeset, and then testing your changes there (or leaving any problems for other contributors to notice and investigate later). This can be especially useful for certain kinds of changes, such as changes to routing restrictions, where you may want to query several example routes to ensure that your restriction only affected the intended routes.
In general, the testing process works like this:
- First, you need to have access to an instance of the application in which you have the ability to load custom data. For an application designed to run on your own computer or phone (such as OsmAnd), this may be as easy as installing the application the normal way, whereas for a web-based application (such as OSRM), the process to install your own instance is often not very user-friendly. (Providing shared instances of popular web-based applications that allow contributors to load custom data for testing would be an interesting future possibility for the community.)
- Then, you load your data. Typically, you have your editor save a JOSM-style OSM file of a small region that includes your change. Then you convert the OSM file to an application-specific format by a process similar to the one used by the main instance of the application on the official map, but just on your small custom file, so the computing resources required will typically be much lower than what the documentation suggests for large regions of the map.
The rest of this page has some details about testing changes in particular applications.
OsmAnd
OsmAnd is one of the best applications for testing changes because loading custom data is relatively easy and the set of things you can test is relatively complete (notably, routing). Use OsmAndMapCreator to convert the OSM file to OsmAnd's OBF format and follow the instructions to install your OBF file on your phone. When you're done testing, just delete your OBF file and reactivate the official map of the region.
One feature that would be useful for testing that OsmAnd doesn't have as of this writing is the ability to set a custom time to evaluate conditional restrictions (unless you're willing to change your phone's system clock or use an emulator, etc.).