This repo contains code for three functions to be loaded into PostgreSQL as a shared library:
1. `maptile_for_point`, which is used only by the `/changes` API call. This API call is little-used and IMHO should be deprecated and removed. However, even now it's hardly on the hot path for most development activities.
2. `tile_for_point`, which is used only in migrations. At this point, it seems unlikely that anyone will be doing a migration on existing data which would call this function (most developers will be running migrations on an empty database, to set it up).
3. `xid_to_int4`, which is only used for replication using Osmosis and isn't used in the Rails code at all. Hopefully this will be replaced Real Soon Now, but until then it's a quite advanced feature that most developers won't need.
Therefore, this patch proposes to replace the above three shared library functions with SQL implementations of the first two. These are _much_ slower - by a factor of about 30x, however this makes no difference when they're run on a completely empty database. In return, we're able to drop a dependency on the PostgreSQL server development package, and clean a few lines out of the installation instructions.
It's still possible to make and install the shared library functions, and I've included instructions about how to do that - although it shouldn't be necessary for the vast majority of `openstreetmap-website` developers.
In bundle < 2.0, warnings are printed to stdout, along with the path information
that we need. This takes the final line of the output and assumes it's the path.
Fixes#1930
Quad tile functions are now installed via a gem with native extension
automatically. This improves the run time of the test suite by ~30% for
users that didn't bother to build the C version of the functions.
Closes#1314Closes#1899
