fix: enable support for firebasedatabase.app

Author: thameezb

db/db.go

@@ -48,8 +48,8 @@ func NewClient(ctx context.Context, c *internal.DatabaseConfig) (*Client, error)
 		return nil, err
 	} else if p.Scheme != "https" {
 		return nil, fmt.Errorf("invalid database URL: %q; want scheme: %q", c.URL, "https")
-	} else if !strings.HasSuffix(p.Host, ".firebaseio.com") {
-		return nil, fmt.Errorf("invalid database URL: %q; want host: %q", c.URL, "firebaseio.com")
+	} else if !(strings.HasSuffix(p.Host, ".firebaseio.com") || strings.HasSuffix(p.Host, ".firebasedatabase.app")) {
+		return nil, fmt.Errorf("invalid database URL: %q; want host: %q or %q", c.URL, "firebaseio.com", ".firebasedatabase.app")
 	}
 
 	var ao []byte

db/db_test.go

@@ -136,6 +136,25 @@ func TestNewClientAuthOverrides(t *testing.T) {
 	}
 }
 
+func TestValidURLS(t *testing.T) {
+	cases := []string{
+		"https://test-db.firebaseio.com",
+		"https://test-db.firebasedatabase.app",
+	}
+	for _, tc := range cases {
+		c, err := NewClient(context.Background(), &internal.DatabaseConfig{
+			Opts: testOpts,
+			URL:  tc,
+		})
+		if err != nil {
+			t.Fatal(err)
+		}
+		if c.url != tc {
+			t.Errorf("NewClient(%v).url = %q; want = %q", tc, c.url, testURL)
+		}
+	}
+}
+
 func TestInvalidURL(t *testing.T) {
 	cases := []string{
 		"",