Add location bias for geocoding

Author: rinigus

README.api.md

@@ -193,6 +193,23 @@ where meaning of the query parameters is the same as for the version
 one. However, the result includes parsing feedback when geocoder-nlp
 is used, see [example](examples/search_v2.json).
 
+### Location bias, supported by versions 1 and 2
+
+Optional parameters can be used for location bias of geocoding:
+
+`lng={lng}` - longitude for reference location, must be specified for bias
+
+`lat={lat}` - latitude for reference location, must be specified for bias
+
+`zoom={zoom}` - zoom level of a map used as a basemap for showing
+search result. This level is used to calculate location bias reference
+distance. This is an optional integer parameter with the default value
+of 16.
+
+`importance={importance}` - importance of location bias (range from
+0.0-1.0, 1.0 corresponding to high location bias). This is an optional
+parameter with the default value of 0.75.
+
 
 ## List of available POI types
 

server/src/geomaster.cpp

@@ -287,7 +287,8 @@ static std::string v2s(const std::vector<std::string> &v)
   return s;
 }
 
-bool GeoMaster::search(const QString &searchPattern, QJsonObject &result, size_t limit,
+bool GeoMaster::search(const QString &searchPattern, QJsonObject &result,
+                       const GeoNLP::Geocoder::GeoReference &reference, size_t limit,
                        double &lat, double &lon, std::string &name, size_t &number_of_results)
 {
   QMutexLocker lk(&m_mutex);
@@ -378,7 +379,7 @@ bool GeoMaster::search(const QString &searchPattern, QJsonObject &result, size_t
       // search
       m_geocoder.set_max_results(limit);
       std::vector<GeoNLP::Geocoder::GeoResult> search_result_country;
-      if ( !m_geocoder.search(parsed_query, search_result_country, levels_resolved) )
+      if ( !m_geocoder.search(parsed_query, search_result_country, levels_resolved, reference) )
         {
           InfoHub::logError(tr("Error while searching with geocoder-nlp"));
           return false;
@@ -412,6 +413,7 @@ bool GeoMaster::search(const QString &searchPattern, QJsonObject &result, size_t
   result.insert("query", searchPattern);
   result.insert("parsed", parsed);
   result.insert("parsed_normalized", parsed_normalized);
+  result.insert("reference_used", reference.is_set() ? 1 : 0);
 
   {
     QJsonArray arr;
@@ -452,8 +454,9 @@ bool GeoMaster::search(const QString &searchPattern, double &lat, double &lon, s
 {
   QJsonObject obj;
   size_t number_of_results;
+  GeoNLP::Geocoder::GeoReference reference;
 
-  if ( !search(searchPattern, obj, 1, lat, lon, name, number_of_results ) )
+  if ( !search(searchPattern, obj, reference, 1, lat, lon, name, number_of_results ) )
     {
       InfoHub::logWarning("Search for reference point failed");
       return false;
@@ -466,14 +469,14 @@ bool GeoMaster::search(const QString &searchPattern, double &lat, double &lon, s
   return false;
 }
 
-bool GeoMaster::searchExposed(const QString &searchPattern, QByteArray &result, size_t limit, bool full_result)
+bool GeoMaster::searchExposed(const QString &searchPattern, QByteArray &result, GeoNLP::Geocoder::GeoReference reference, size_t limit, bool full_result)
 {
   QJsonObject sres;
   double lat, lon;
   std::string name;
   size_t number_of_results;
 
-  if ( !search(searchPattern, sres, limit, lat, lon, name, number_of_results ) )
+  if ( !search(searchPattern, sres, reference, limit, lat, lon, name, number_of_results ) )
     return false;
 
   if (!full_result)

server/src/geomaster.h

@@ -63,7 +63,9 @@ class GeoMaster : public QObject
   /// \param result
   /// \param limit
   /// \return
-  bool searchExposed(const QString &searchPattern, QByteArray &result, size_t limit, bool full_result);
+  bool searchExposed(const QString &searchPattern, QByteArray &result,
+                     GeoNLP::Geocoder::GeoReference reference,
+                     size_t limit, bool full_result);
 
   /////////////////////////////////////////////////////////////
   /// \brief Search for a pattern and return the coordinates of the first found object
@@ -103,7 +105,8 @@ public slots:
   void warnLargeRamLangNotSpecifiedChanged(bool warning);
 
 protected:
-  bool search(const QString &searchPattern, QJsonObject &result, size_t limit,
+  bool search(const QString &searchPattern, QJsonObject &result, const
+              GeoNLP::Geocoder::GeoReference &reference, size_t limit,
               double &lat, double &lon, std::string &name, size_t &number_of_results);
 
   void checkWarnings(bool lang_specified);

server/src/requestmapper.cpp

@@ -638,6 +638,11 @@ unsigned int RequestMapper::service(const char *url_c,
       bool ok = true;
       size_t limit = q2value<size_t>("limit", 25, options, connection, ok);
       QString search = q2value<QString>("search", "", options, connection, ok);
+      double lon = q2value<double>("lng", 0, options, connection, ok);
+      double lat = q2value<double>("lat", 0, options, connection, ok);
+      size_t zoom = q2value<size_t>("zoom", 16, options, connection, ok);
+      double importance = q2value<double>("importance", 0.75, options, connection, ok);
+      GeoNLP::Geocoder::GeoReference reference;
 
       search = search.simplified();
 
@@ -647,6 +652,10 @@ unsigned int RequestMapper::service(const char *url_c,
           return MHD_HTTP_BAD_REQUEST;
         }
 
+      if (has("lng", options, connection) &&
+          has("lat", options, connection))
+        reference.set(lat, lon, zoom, importance);
+
       Task *task;
       bool extended_reply = (path == "/v2/search");
 
@@ -660,7 +669,7 @@ unsigned int RequestMapper::service(const char *url_c,
 #endif
         task = new Task(connection_id,
                         std::bind( &GeoMaster::searchExposed, GeoMaster::instance(),
-                                   search, std::placeholders::_1, limit,
+                                   search, std::placeholders::_1, reference, limit,
                                    extended_reply),
                         "Error while searching");