We just released GOL Tool 2.3, which now allows you to export the results of a query in OSM PBF format. This makes it easy to create regional or thematic extracts.

You can also filter tags using the --keys (-k) option.

Example:

gol query germany na[amenity=restaurant] 
    -a bavaria.wkt 
    -k amenity,cuisine,opening_hours 
    > restaurants.osm.pbf

This queries germany.gol and creates a PBF containing all restaurants in Bavaria (specified as a Well-Known Text multipolygon), including only the amenity, cuisine and opening_hours tags.

To ensure that untagged way-nodes are included in the output, build or load your GOL with the --waynode-ids (-w) option.

To get the (multi)polygon for the query’s --area (-a) option, first export the desired region like this:

gol query germany a[boundary=administrative][name:en=Bavaria] 
    > bavaria.wkt

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