`osm_date` not set for graphs build from files processed with osm-transform

[aoles]

Problem description

The osm_date field in the response from an ORS instance configured against the graph store remains set to the initial value of "1970-01-01T00:00:00Z", as in the following example query.

 $ curl -X POST \
  'https://api.openrouteservice.org/v2/directions/logie-car' \
  -H 'Content-Type: application/json; charset=utf-8' \
  -H 'Accept: application/json, application/geo+json, application/gpx+xml, img/png; charset=utf-8' \
  -H 'Authorization: <API_KEY>' \
  -d '{"coordinates":[[43.67977380752564, 3.1339384711926193],[43.6762547492981, 3.138694939439161]],"instructions":"false","geometry":"false"}'

{
   "bbox":[
      43.67623,
      3.133947,
      43.682263,
      3.139295
   ],
   "routes":[
      {
         "summary":{
            "distance":1466.2,
            "duration":212.3
         },
         "bbox":[
            43.67623,
            3.133947,
            43.682263,
            3.139295
         ]
      }
   ],
   "metadata":{
      "attribution":"openrouteservice.org | OpenStreetMap contributors",
      "service":"routing",
      "timestamp":1759311062251,
      "query":{
         "coordinates":[
            [
               43.67977380752564,
               3.1339384711926193
            ],
            [
               43.6762547492981,
               3.138694939439161
            ]
         ],
         "profile":"driving-car",
         "profileName":"logie-car",
         "format":"json"
      },
      "engine":{
         "version":"9.4.0",
         "build_date":"2025-09-22T15:33:11Z",
         "graph_date":"2025-09-27T23:30:57Z",
         "osm_date":"1970-01-01T00:00:00Z"
      },
      "system_message":"This is a test instance of openrouteservice, using the staging configuration."
   }
}

Normally, the field is expected to contain the snapshot date of the OSM data from the PBF used for building the graphs.

$ curl -X POST \
>   'https://api.openrouteservice.org/v2/directions/driving-car' \
>   -H 'Content-Type: application/json; charset=utf-8' \
>   -H 'Accept: application/json, application/geo+json, application/gpx+xml, img/png; charset=utf-8' \
>   -H 'Authorization: <API_KEY>' \
>   -d '{"coordinates":[[43.67977380752564, 3.1339384711926193],[43.6762547492981, 3.138694939439161]],"instructions":"false","geometry":"false"}'

{
   "bbox":[
      43.67623,
      3.133947,
      43.682263,
      3.139295
   ],
   "routes":[
      {
         "summary":{
            "distance":1466.2,
            "duration":212.3
         },
         "bbox":[
            43.67623,
            3.133947,
            43.682263,
            3.139295
         ]
      }
   ],
   "metadata":{
      "attribution":"openrouteservice.org | OpenStreetMap contributors",
      "service":"routing",
      "timestamp":1759839376477,
      "query":{
         "coordinates":[
            [
               43.67977380752564,
               3.1339384711926193
            ],
            [
               43.6762547492981,
               3.138694939439161
            ]
         ],
         "profile":"driving-car",
         "profileName":"driving-car",
         "format":"json"
      },
      "engine":{
         "version":"9.3.0",
         "build_date":"2025-06-06T15:39:25Z",
         "graph_date":"2025-10-05T11:13:35Z",
         "osm_date":"2025-09-29T00:00:01Z"
      }
   }
}

Proposed solution

Investigate the root cause and come up with a solution to the described issue.

[aoles]

The actual issue seems to be the missing OSM timestamp in file header.