feat(database): support optional endAt/equalTo key

docs/4-querying-lists.md

@@ -25,13 +25,13 @@ const queryObservable = af.database.list('/items', {
 | `orderByKey` | Boolean to order by Firebase Database keys. |
 | `orderByPriority` | Boolean to order by Firebase Database priority. |
 | `orderByValue` | Specify a value to order by. |
-| `equalTo` | Limit list to items that contain certain value. |
+| `equalTo` <sup>1</sup> | Limit list to items that contain certain value. |
 | `limitToFirst` | Sets the maximum number of items to return from the beginning of the ordered list of results. |
 | `limitToLast` | Sets the maximum number of items to return from the end of the ordered list of results. |
 | `startAt` <sup>1</sup> | Return items greater than or equal to the specified key or value, depending on the order-by method chosen. |
-| `endAt` | Return items less than or equal to the specified key or value, depending on the order-by method chosen. |
+| `endAt` <sup>1</sup> | Return items less than or equal to the specified key or value, depending on the order-by method chosen. |
 
-<sup>1</sup> The Firebase SDK supports [an optional `key` parameter](https://firebase.google.com/docs/reference/js/firebase.database.Reference#startAt) when ordering by child, value, or priority. You can specify the `key` parameter using `startAt: { value: 'some-value', key: 'some-key' }`
+<sup>1</sup> The Firebase SDK supports an optional `key` parameter for [`startAt`](https://firebase.google.com/docs/reference/js/firebase.database.Reference#startAt), [`endAt`](https://firebase.google.com/docs/reference/js/firebase.database.Reference#endAt), and [`equalTo`](https://firebase.google.com/docs/reference/js/firebase.database.Reference#equalTo) when ordering by child, value, or priority. You can specify the `key` parameter using an object literal that contains the `value` and the `key`. For example: `startAt: { value: 'some-value', key: 'some-key' }`.
 
 ## Invalid query combinations
 

src/database/firebase_list_factory.spec.ts

@@ -761,6 +761,86 @@ describe('FirebaseListFactory', () => {
 
     });
 
+    describe('equalTo(value, key)', () => {
+
+      it('should support the optional key parameter to equalTo', (done) => {
+
+        questions.$ref.ref.set({
+          val1: Object.assign({}, val1, { data: 0 }),
+          val2: Object.assign({}, val2, { data: 0 }),
+          val3: Object.assign({}, val3, { data: 0 })
+        })
+        .then(() => {
+
+          let query1 = FirebaseListFactory(`${rootDatabaseUrl}/questions`, {
+            query: {
+              orderByChild: 'data',
+              equalTo: { value: 0 }
+            }
+          });
+          query1 = take.call(query1, 1);
+          query1 = toPromise.call(query1);
+
+          let query2 = FirebaseListFactory(`${rootDatabaseUrl}/questions`, {
+            query: {
+              orderByChild: 'data',
+              equalTo: { value: 0, key: 'val2' }
+            }
+          });
+          query2 = take.call(query2, 1);
+          query2 = toPromise.call(query2);
+
+          Promise.all([query1, query2]).then(([list1, list2]) => {
+            expect(list1.map(i => i.$key)).toEqual(['val1', 'val2', 'val3']);
+            expect(list2.map(i => i.$key)).toEqual(['val2']);
+            done();
+          });
+        })
+        .catch(done.fail);
+      });
+
+    });
+
+    describe('endAt(value, key)', () => {
+
+      it('should support the optional key parameter to endAt', (done) => {
+
+        questions.$ref.ref.set({
+          val1: Object.assign({}, val1, { data: 0 }),
+          val2: Object.assign({}, val2, { data: 0 }),
+          val3: Object.assign({}, val3, { data: 0 })
+        })
+        .then(() => {
+
+          let query1 = FirebaseListFactory(`${rootDatabaseUrl}/questions`, {
+            query: {
+              orderByChild: 'data',
+              endAt: { value: 0 }
+            }
+          });
+          query1 = take.call(query1, 1);
+          query1 = toPromise.call(query1);
+
+          let query2 = FirebaseListFactory(`${rootDatabaseUrl}/questions`, {
+            query: {
+              orderByChild: 'data',
+              endAt: { value: 0, key: 'val2' }
+            }
+          });
+          query2 = take.call(query2, 1);
+          query2 = toPromise.call(query2);
+
+          Promise.all([query1, query2]).then(([list1, list2]) => {
+            expect(list1.map(i => i.$key)).toEqual(['val1', 'val2', 'val3']);
+            expect(list2.map(i => i.$key)).toEqual(['val1', 'val2']);
+            done();
+          });
+        })
+        .catch(done.fail);
+      });
+
+    });
+
     describe('observable queries (issue #830)', () => {
 
       it('should not emit the results of previous queries', (done) => {

src/database/firebase_list_factory.ts

@@ -50,7 +50,11 @@ export function FirebaseListFactory (
 
       // check equalTo
       if (utils.hasKey(query, "equalTo")) {
-        queried = queried.equalTo(query.equalTo);
+        if (utils.hasKey(query.equalTo, "value")) {
+          queried = queried.equalTo(query.equalTo.value, query.equalTo.key);
+        } else {
+          queried = queried.equalTo(query.equalTo);
+        }
 
         if (utils.hasKey(query, "startAt") || utils.hasKey(query, "endAt")) {
           throw new Error('Query Error: Cannot use startAt or endAt with equalTo.');
@@ -78,7 +82,11 @@ export function FirebaseListFactory (
       }
 
       if (utils.hasKey(query, "endAt")) {
+        if (utils.hasKey(query.endAt, "value")) {
+          queried = queried.endAt(query.endAt.value, query.endAt.key);
+        } else {
           queried = queried.endAt(query.endAt);
+        }
       }
 
       if (!utils.isNil(query.limitToFirst) && query.limitToLast) {