One of the killer features of OpenStreetMap, which makes it completely different to Google Maps and the rest, is that we provide totally free geodata. In fact it’s really the primary purpose of OpenStreetMap – the various maps shown on the homepage are just a tasty preview.
For those of us lacking the time, money and skills enjoyed by some of the cooler data users (i.e. unable to run a dedicated server with a PostgreSQL database and all the programs and storage space needed to maintain an up-to-date clone of the OpenStreetMap database) there are two main ways to grab OpenStreetMap data.
One is to simply download a defined area using the API. The “export” tab on the web site and editors like JOSM make this easy. The disadvantage is that you get everything in that area. If you wanted to get, say, all the power generators in the UK you would need to download and process gigabytes of data for the whole of the UK to pull them out.
Thankfully we have the wonderful eXtended API (XAPI, or “zappy”). This lets you define the features you want to download, and the area you want them for. So I can easily download a small file just containing power generators in the UK.
I have used XAPI for my OpenEcoMaps project. It’s great. It lets me build a web site on cheap shared hosting without needing ninja data processing skills. I love it.
Unfortunately, for the past few months XAPI has gradually become so overloaded that it is useless. I don’t think I have been able to make a batch of five calls for data from XAPI for weeks. OpenEcoMaps tries to download fresh data every hour, to no avail. Downloads either time out, return empty files, or return partial files that stop half-way through.
As a result I’ve not been able to launch OpenEcoMaps, and I’ve had to slow down conversations with local community groups, charities, councils and regional government about various exciting collaboration ideas.
I don’t begrudge hard-pressed volunteers who set XAPI up, especially when so much good work has gone into making the main web site, the default map, the wiki and the underlying database run so reliably.
But I wish and cross my fingers for the day when there is a resource – either from the community or a company – to run a reliable XAPI service. I’d even be willing to pay a small annual fee for access. In the meantime, sadly for me, the work I’ve been building up over the past few years networking with those other groups has ground to a halt because of my inability to get data out of OpenStreetMap. Suggestions are welcome.