Allow query on collection group (#10)

* Allow query on collection group

Fix #8

* Fix tests

* Update README.md

* Fix tests

README.md

@@ -69,6 +69,7 @@ Read the [documentation](https://pgollangi.github.io/FireQL/) for more informati
 Some cool `SELECT` queries that are possible with `FireQL`:
 ```sql
 select * from users
+select * from `[contacts]` // To query collection group. enclose subcollect name in square brackets.
 select *, id as user_id from users
 select id, email as email_address, `address.city` AS city from `users`
 select * from users order by 'address.city' desc limit 10

pkg/select/select.go

@@ -55,8 +55,15 @@ func (sel *SelectStatement) Execute() (*util.QueryResult, error) {
 	defer fireClient.Close()
 
 	qCollectionName = strings.Trim(qCollectionName, "`")
-	fCollection := fireClient.Collection(qCollectionName)
-	fQuery := fCollection.Query
+
+	var fQuery firestore.Query
+	if strings.HasPrefix(qCollectionName, "[") && strings.HasSuffix(qCollectionName, "]") {
+		groupName := strings.TrimPrefix(qCollectionName, "[")
+		groupName = strings.TrimSuffix(groupName, "]")
+		fQuery = fireClient.CollectionGroup(groupName).Query
+	} else {
+		fQuery = fireClient.Collection(qCollectionName).Query
+	}
 
 	fQuery, selectedFields, err := sel.selectFields(fQuery, sQuery)
 	if err != nil {

pkg/select/select_test.go

@@ -35,6 +35,11 @@ var selectTests = []TestExpect{
 		columns: []string{"id", "email", "username", "address", "name"},
 		length:  "21",
 	},
+	TestExpect{
+		query:   "select * from `users`",
+		columns: []string{"id", "email", "username", "address", "name"},
+		length:  "21",
+	},
 	TestExpect{
 		query:   "select id as uid, * from users",
 		columns: []string{"uid", "id", "email", "username", "address", "name"},
@@ -97,7 +102,7 @@ func newFirestoreTestClient(ctx context.Context) *firestore.Client {
 
 func TestMain(m *testing.M) {
 	// command to start firestore emulator
-	cmd := exec.Command("gcloud", "beta", "emulators", "firestore", "start", "--host-port=localhost")
+	cmd := exec.Command("gcloud", "beta", "emulators", "firestore", "start", "--host-port=localhost:8765")
 
 	// this makes it killable
 	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}
@@ -151,19 +156,14 @@ func TestMain(m *testing.M) {
 					wg.Done()
 				}
 
-				// and capturing the FIRESTORE_EMULATOR_HOST value to set
-				pos := strings.Index(d, FirestoreEmulatorHost+"=")
-				if pos > 0 {
-					host := d[pos+len(FirestoreEmulatorHost)+1 : len(d)-1]
-					os.Setenv(FirestoreEmulatorHost, host)
-				}
 			}
 		}
 	}()
 
 	// wait until the running message has been received
 	wg.Wait()
 
+	os.Setenv(FirestoreEmulatorHost, "localhost:8765")
 	ctx := context.Background()
 	users := newFirestoreTestClient(ctx).Collection("users")