How to use the osm-p2p-server/api/index function in osm-p2p-server

.then(poiTypes => {
      const bbox = [-180, -90, 180, 90];
      const toOsmOptions = {
        bounds: {minlon: bbox[0], minlat: bbox[1], maxlon: bbox[2], maxlat: bbox[3]}
      };
      const osmDb = getDatabase(projId, scId);
      const formatTransform = obj2osm(toOsmOptions);

      formatTransform.on('error', (err) => {
        throw err;
      });

      logger && logger.log('Exporting data from osm-p2p');

      let stream = osmP2PApi(osmDb).getMap(bbox, {order: 'type'})
        .pipe(processOSMP2PExport());

      // Extract the POI into a promise and continue with the road network.
      let splitting = collectPOIs(stream, poiTypes);

      stream = splitting.stream.pipe(formatTransform);

      function processRN () {
        const fileName = `road-network_${Date.now()}`;
        const filePath = `scenario-${scId}/${fileName}`;

        return putFileStream(filePath, stream)
          // Get previous file.
          .then(() => db('scenarios_files')
            .select('path')
            .where('type', 'road-network')