This is a library for extracting OSM entities from PBF files. It is intended to be used for simple one-off tasks, searching an area of no more than a few square kilometers, where setting up a PostgreSQL database would be a disproportionate effort.
It performs reasonably well when working with OSM extracts, such as the ones obtained from download.geofabrik.de. With modest hardware (e.g. an old ThinkPad T480) PBF files can be read at roughly 80MiB/s to 300MiB/s. When reading through an extract of the Czech Republic (828MiB), roughly 320MiB of RAM are used (but this will depend on the amount of cores on your CPU).
Performance can be improved, by changing the compression inside PBF files to zstd. This can be done with the zstd-pbf tool.
Find the full documentation of this library at godocs.io/github.com/codesoap/pbf.
filter := pbf.Filter{
Location: func(lat, lon int64) bool {
// A square filter matching the city center of Bremen, Germany.
return lat >= 53_071_495_496 &&
lat <= 53_080_504_504 &&
lon >= 8_799_510_372 &&
lon <= 8_814_489_628
},
Tags: map[string][]string{
// Find bicycle shops.
"shop": {"bicycle"},
},
}
// wget https://download.geofabrik.de/europe/germany/bremen-latest.osm.pbf
results, err := pbf.ExtractEntities("/tmp/bremen-latest.osm.pbf", filter)
resultCount := len(results.Nodes) + len(results.Ways) + len(results.Relations)
fmt.Printf("Found %d bicycle shop(s) in the center of Bremen.\n", resultCount)To generate some protobuf related code, you need the protoc tool, the
protoc-gen-go tool and the protoc-gen-go-vtproto tool; the latter
two can be installed like this:
go install google.golang.org/protobuf/cmd/protoc-gen-go@v1.34.2
go install github.com/planetscale/vtprotobuf/cmd/protoc-gen-go-vtproto@v0.6.0
For now, ways and relations will be incomplete, if they only partially lie within the location filter or their members didn't match the tag filter. This is undesirable, for example, when trying to render an extracted area as an image. Thus it would be useful to have a flag that makes the library return "ancillary entities". An idea for the interface can be found at commit 9b673e35bd0510e4ad53a2875dcf4a7ea4ca085a.