Support `convert result ::=::,::geom=geom(),length=length(); `

[tordans]

In drolbr/Overpass-API#237 (comment) @drolbr showed this handy way to inject the length of a way into the tags of the osm-tags output.

Unfortunately, that breaks osmtogeojson. When I try to convert, I get an empty result

This works

https://olbricht.nrw/ovt/?Q=%5Bout%3Ajson%5D%3B%0Away%5B%22highway%22%3D%22service%22%5D(%7B%7Bbbox%7D%7D)%3B%0Aout%20geom%3B&C=41.89409;12.49391;20&R

[out:json];
way["highway"="service"]({{bbox}});
out geom;

Output

{
  "version": 0.6,
  "generator": "Overpass API 0.7.56.8 7d656e78",
  "osm3s": {
    "timestamp_osm_base": "2021-11-15T18:29:14Z",
    "copyright": "The data included in this document is from www.openstreetmap.org. The data is made available under ODbL."
  },
  "elements": [

{
  "type": "way",
  "id": 23694377,
  "bounds": {
    "minlat": 41.8943972,
    "minlon": 12.4938181,
    "maxlat": 41.8948117,
    "maxlon": 12.4938504
  },
  "nodes": [
    3134209747,
    256573077,
    256573071
  ],
  "geometry": [
    { "lat": 41.8948117, "lon": 12.4938504 },
    { "lat": 41.8947155, "lon": 12.4938459 },
    { "lat": 41.8943972, "lon": 12.4938181 }
  ],
  "tags": {
    "foot": "yes",
    "highway": "service",
    "name": "Via Monte Polacco",
    "service": "alley",
    "surface": "sett"
  }
},
{
  "type": "way",
  "id": 140757469,
  "bounds": {
    "minlat": 41.8940306,
    "minlon": 12.4943443,
    "maxlat": 41.8942735,
    "maxlon": 12.4949911
  },
  "nodes": [
    1541394684,
    1541394687,
    1541394738,
    1541394751,
    3545433320,
    1541394743,
    3545433319,
    1541394616,
    1541394611,
    1541394620,
    1541394655,
    1541394668,
    1541394684
  ],
  "geometry": [
    { "lat": 41.8942435, "lon": 12.4943814 },
    { "lat": 41.8942381, "lon": 12.4945093 },
    { "lat": 41.8942386, "lon": 12.4947562 },
    { "lat": 41.8942735, "lon": 12.4949444 },
    { "lat": 41.8942665, "lon": 12.4949911 },
    { "lat": 41.8942443, "lon": 12.4949835 },
    { "lat": 41.8941869, "lon": 12.4948972 },
    { "lat": 41.8940349, "lon": 12.4945142 },
    { "lat": 41.8940306, "lon": 12.4944422 },
    { "lat": 41.8940584, "lon": 12.4943616 },
    { "lat": 41.8940992, "lon": 12.4943443 },
    { "lat": 41.8941506, "lon": 12.4943529 },
    { "lat": 41.8942435, "lon": 12.4943814 }
  ],
  "tags": {
    "access": "private",
    "highway": "service",
    "service": "parking_aisle",
    "surface": "asphalt"
  }
},
{
  "type": "way",
  "id": 140757481,
  "bounds": {
    "minlat": 41.8941137,
    "minlon": 12.4939823,
    "maxlat": 41.8942462,
    "maxlon": 12.4943814
  },
  "nodes": [
    1541394684,
    1541394734,
    1541394717,
    1541394666,
    1541394660
  ],
  "geometry": [
    { "lat": 41.8942435, "lon": 12.4943814 },
    { "lat": 41.8942462, "lon": 12.4943089 },
    { "lat": 41.8942317, "lon": 12.4942490 },
    { "lat": 41.8941404, "lon": 12.4940229 },
    { "lat": 41.8941137, "lon": 12.4939823 }
  ],
  "tags": {
    "access": "private",
    "highway": "service",
    "service": "driveway"
  }
},
{
  "type": "way",
  "id": 348410740,
  "bounds": {
    "minlat": 41.8937940,
    "minlon": 12.4938787,
    "maxlat": 41.8939344,
    "maxlon": 12.4942016
  },
  "nodes": [
    3545433304,
    3545433303,
    3545433301
  ],
  "geometry": [
    { "lat": 41.8939344, "lon": 12.4942016 },
    { "lat": 41.8939152, "lon": 12.4941676 },
    { "lat": 41.8937940, "lon": 12.4938787 }
  ],
  "tags": {
    "highway": "service"
  }
}

  ]
}

And transforming it via http://tyrasd.github.io/osmtogeojson/ works.

This does not work

https://olbricht.nrw/ovt/?Q=%5Bout%3Ajson%5D%3B%0Away%5B%22highway%22%3D%22service%22%5D(%7B%7Bbbox%7D%7D)%3B%0Aconvert%20result%20%3A%3A%3D%3A%3A%2C%3A%3Ageom%3Dgeom()%2Clength%3Dlength()%3B%0Aout%20geom%3B&C=41.89409;12.49391;20&R

[out:json];
way["highway"="service"]({{bbox}});
convert result ::=::,::geom=geom(),length=length();
out geom;

Output

{
  "version": 0.6,
  "generator": "Overpass API 0.7.57 93a4d346",
  "osm3s": {
    "timestamp_osm_base": "2021-11-15T18:16:02Z",
    "copyright": "The data included in this document is from www.openstreetmap.org. The data is made available under ODbL."
  },
  "elements": [

{
  "type": "result",
  "id": 1,
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [12.4942016, 41.8939344],
      [12.4941676, 41.8939152],
      [12.4938787, 41.8937940]
    ]
  },
  "tags": {
    "highway": "service",
    "length": "30.959"
  }
},
{
  "type": "result",
  "id": 2,
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [12.4938504, 41.8948117],
      [12.4938459, 41.8947155],
      [12.4938181, 41.8943972]
    ]
  },
  "tags": {
    "foot": "yes",
    "highway": "service",
    "name": "Via Monte Polacco",
    "service": "alley",
    "surface": "sett",
    "length": "46.137"
  }
},
{
  "type": "result",
  "id": 3,
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [12.4943814, 41.8942435],
      [12.4945093, 41.8942381],
      [12.4947562, 41.8942386],
      [12.4949444, 41.8942735],
      [12.4949911, 41.8942665],
      [12.4949835, 41.8942443],
      [12.4948972, 41.8941869],
      [12.4945142, 41.8940349],
      [12.4944422, 41.8940306],
      [12.4943616, 41.8940584],
      [12.4943443, 41.8940992],
      [12.4943529, 41.8941506],
      [12.4943814, 41.8942435]
    ]
  },
  "tags": {
    "access": "private",
    "highway": "service",
    "service": "parking_aisle",
    "surface": "asphalt",
    "length": "133.432"
  }
},
{
  "type": "result",
  "id": 4,
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [12.4943814, 41.8942435],
      [12.4943089, 41.8942462],
      [12.4942490, 41.8942317],
      [12.4940229, 41.8941404],
      [12.4939823, 41.8941137]
    ]
  },
  "tags": {
    "access": "private",
    "highway": "service",
    "service": "driveway",
    "length": "36.969"
  }
}

  ]
}

Transforming it via http://tyrasd.github.io/osmtogeojson/ returns:

{
"type": "FeatureCollection",
"features": [

]
}

[tordans]

Update in case someone finds this in search for a workaround: I build my own GeoJSON transformation.

I was using the stats workaround described in drolbr/Overpass-API#237 (comment) before and used this script https://github.com/FixMyBerlin/osm-scripts/blob/7c70603210bc4dbf9f334e61f7dedb5da70cb4c4/ZESPlus/utils/transpose/_addLenghtFromOverpassStatsResultToGeoJson.ts to re-add the length as properties to the OSM-ways.

However, that had bad performance. I am now using convert approach described above and use a custom transformation to create GeoJSON from the output.

• Example Query FixMyBerlin/osm-scripts@7c70603#diff-de511de8bd72881c9647915c9ee442abdcab5bbc9b4092de6af427195575a35fR14-R24
• Overpass-Compose-JSON-To-GeoJSON: FixMyBerlin/osm-scripts@7c70603#diff-72dcf37f75222b49e691fbb4915bbec0ba2193b6de389e2bd93721423e2b0313R28-R50
• An important part to get this running is, to add the OSM-id and OSM-type to the output which can them be used to re-create the OSM-ID.
  Example convert result ::=::,::geom= geom(),::id=id(),"__type"=type(),"FMC:length"=length(); (based on the initial example but with id and __type).

For this ticket, this also means, that it is not easy to just support the generated JSON since essential info (OSM id and OSM type) are missing by default.