"Near" fix for where clauses

See loopbackio#993 for original code

Tests for "Near" fix for where clause

See loopbackio#993 for original code

Fix `nearFilter` key array

Author: viki53

lib/geo.js

@@ -9,80 +9,119 @@ var assert = require('assert');
 
 /*!
  * Get a near filter from a given where object. For connector use only.
+ * NB: This only supports one near parameter per where object.  eg, this:
+ * {where: {or: [{location: {near: "29,-90"}},{location: {near: "50,-72"}}]}}
+ * would throw an error.
  */
 
 exports.nearFilter = function nearFilter(where) {
-  var result = false;
-
-  if (where && typeof where === 'object') {
-    Object.keys(where).forEach(function(key) {
-      var ex = where[key];
-
-      if (ex && ex.near) {
-        result = {
-          near: ex.near,
-          maxDistance: ex.maxDistance,
-          unit: ex.unit,
-          key: key,
-        };
+  function nearSearch(clause, parentKeys) {
+    if (typeof clause !== 'object') {
+      return false;
+    }
+    if (!parentKeys) {
+      parentKeys = [];
+    }
+
+    Object.keys(clause).forEach(function(clauseKey) {
+      if (Array.isArray(clause[clauseKey])) {
+        clause[clauseKey].forEach(function(el) {
+          var ret = nearSearch(el, parentKeys.concat(clauseKey));
+          if (ret) return ret;
+        });
+      } else {
+        if (clause[clauseKey].hasOwnProperty('near')) {
+          var result = clause[clauseKey];
+          nearResults.push({
+            near: result.near,
+            maxDistance: result.maxDistance,
+            unit: result.unit,
+            key: parentKeys.concat(clauseKey),
+          });
+        }
       }
     });
   }
+  var nearResults = [];
+  nearSearch(where);
 
-  return result;
+  if (nearResults.length === 0) {
+    return false;
+  }
+  return nearResults;
 };
 
 /*!
- * Filter a set of objects using the given `nearFilter`.
+ * Filter a set of objects using the given `nearFilter`. Can support multiple
+ * locations, but will include results from all of them.
+ *
+ * WARNING: "or" operator with GeoPoint does not work as expected, eg:
+ * {where: {or: [{location: {near: (29,-90)}},{name:'Sean'}]}}
+ * Will actually work as if you had used "and".  This is because geo filtering
+ * takes place outside of the SQL query, so the result set of "name = Sean" is
+ * returned by the database, and then the location filtering happens in the app
+ * logic.  So the "near" operator is always an "and" of the SQL filters, and "or"
+ * of other GeoPoint filters.
+ *
+ * Additionally, since this step occurs after the SQL result set is returned,
+ * if using GeoPoints with pagination the result set may be smaller than the
+ * page size.  The page size is enforced at the DB level, and then we may
+ * remove results at the Geo-app level.  If we "limit: 25", but 4 of those results
+ * do not have a matching geopoint field, the request will only return 21 results.
+ * This may make it erroneously look like a given page is the end of the result set.
  */
 
 exports.filter = function(arr, filter) {
-  var origin = filter.near;
-  var max = filter.maxDistance > 0 ? filter.maxDistance : false;
-  var unit = filter.unit;
-  var key = filter.key;
-
-  // create distance index
   var distances = {};
   var result = [];
 
-  arr.forEach(function(obj) {
-    var loc = obj[key];
+  filters.forEach(function(filter) {
+    var origin = filter.near;
+    var max = filter.maxDistance > 0 ? filter.maxDistance : false;
+    var unit = filter.unit;
+    var key = filter.key;
 
-    // filter out objects without locations
-    if (!loc) return;
+    // create distance index
+    arr.forEach(function(obj) {
+      var loc = obj[key];
 
-    if (!(loc instanceof GeoPoint)) {
-      loc = GeoPoint(loc);
-    }
+      // filter out objects without locations
+      if (!loc) return;
+
+      if (!(loc instanceof GeoPoint)) {
+        loc = GeoPoint(loc);
+      }
 
-    if (typeof loc.lat !== 'number') return;
-    if (typeof loc.lng !== 'number') return;
+      if (typeof loc.lat !== 'number') return;
+      if (typeof loc.lng !== 'number') return;
 
-    var d = GeoPoint.distanceBetween(origin, loc, {type: unit});
+      var d = GeoPoint.distanceBetween(origin, loc, { type: unit });
 
-    if (max && d > max) {
-      // dont add
-    } else {
-      distances[obj.id] = d;
-      result.push(obj);
-    }
-  });
+      if (max && d > max) {
+        // dont add
+      } else {
+        distances[obj.id] = d;
+        result.push(obj);
+      }
+    });
 
-  return result.sort(function(objA, objB) {
-    var a = objA[key];
-    var b = objB[key];
+    result.sort(function(objA, objB) {
+      var a = objA[key];
+      var b = objB[key];
 
-    if (a && b) {
-      var da = distances[objA.id];
-      var db = distances[objB.id];
+      if (a && b) {
+        var da = distances[objA.id];
+        var db = distances[objB.id];
 
-      if (db === da) return 0;
-      return da > db ? 1 : -1;
-    } else {
-      return 0;
-    }
+        if (db === da) return 0;
+        return da > db ? 1 : -1;
+      } else {
+        return 0;
+      }
+    });
   });
+
+  return result;
 };
 
 exports.GeoPoint = GeoPoint;

test/basic-querying.test.js

@@ -22,6 +22,7 @@ describe('basic-querying', function() {
       role: {type: String, index: true},
       order: {type: Number, index: true, sort: true},
       vip: {type: Boolean},
+      addressLoc: { type: 'GeoPoint' },
     });
 
     db.automigrate(done);
@@ -520,6 +521,48 @@ describe('basic-querying', function() {
       });
     });
 
+    it('should support nested GeoPoint near queries', function(done) {
+      User.find({
+        where: { and: [{ addressLoc: { near: '29.9,-90.07' }}, { vip: true }] },
+      }, function(err, users) {
+        if (err) return done(err);
+        users.should.have.property('length', 2);
+        users[0].addressLoc.should.not.equal(null);
+        done();
+      });
+    });
+
+    it('should support very nested GeoPoint near queries', function(done) {
+      User.find({
+        where: { and: [
+          { and: [{ addressLoc: { near: '29.9,-90.07' }}, { order: 2 }] },
+          { vip: true },
+        ] },
+      }, function(err, users) {
+        if (err) return done(err);
+        users.should.have.property('length', 1);
+        users[0].addressLoc.should.not.equal(null);
+        done();
+      });
+    });
+
+    it('should support multiple GeoPoint near queries', function(done) {
+      User.find({
+        where: { and: [
+          { or: [
+            { addressLoc: { near: '29.9,-90.04', maxDistance: 300 }},
+            { addressLoc: { near: '22.97, -88.03', maxDistance: 300 }},
+          ] },
+          { vip: true },
+        ] },
+      }, function(err, users) {
+        if (err) return done(err);
+        users.should.have.property('length', 2);
+        users[0].addressLoc.should.not.equal(null);
+        done();
+      });
+    });
+
     it('should only include fields as specified', function(done) {
       var remaining = 0;
 
@@ -557,7 +600,9 @@ describe('basic-querying', function() {
       }
 
       sample({name: true}).expect(['name']);
-      sample({name: false}).expect(['id', 'seq', 'email', 'role', 'order', 'birthday', 'vip']);
+      sample({ name: false }).expect([
+        'id', 'seq', 'email', 'role', 'order', 'birthday', 'vip', 'addressLoc'
+      ]);
       sample({name: false, id: true}).expect(['id']);
       sample({id: true}).expect(['id']);
       sample('id').expect(['id']);
@@ -869,6 +914,7 @@ function seed(done) {
       birthday: new Date('1980-12-08'),
       order: 2,
       vip: true,
+      addressLoc: { lat: 29.97, lng: -90.03 },
     },
     {
       seq: 1,
@@ -878,8 +924,15 @@ function seed(done) {
       birthday: new Date('1942-06-18'),
       order: 1,
       vip: true,
+      addressLoc: { lat: 22.97, lng: -88.03 },
+    },
+    {
+      seq: 2,
+      name: 'George Harrison',
+      order: 5,
+      vip: false,
+      addressLoc: { lat: 22.7, lng: -89.03 },
     },
-    {seq: 2, name: 'George Harrison', order: 5, vip: false},
     {seq: 3, name: 'Ringo Starr', order: 6, vip: false},
     {seq: 4, name: 'Pete Best', order: 4},
     {seq: 5, name: 'Stuart Sutcliffe', order: 3, vip: true},