Force refresh token if RPC fails with "Unauthenticated" error (#1373)

"Unauthenticated" is presumed to mean that token is expired (which might happen if local clock is wrong) and retried, subject to the usual backoff logic.

2 files changed, 79 insertions, 0 deletions

diff --git a/Firestore/Example/Tests/Integration/FSTStreamTests.mm b/Firestore/Example/Tests/Integration/FSTStreamTests.mm
index b944a93..3ad6868 100644
--- a/Firestore/Example/Tests/Integration/FSTStreamTests.mm
+++ b/Firestore/Example/Tests/Integration/FSTStreamTests.mm
@@ -18,8 +18,11 @@
 
 #import <GRPCClient/GRPCCall.h>
 
+#import <FirebaseFirestore/FIRFirestoreErrors.h>
 #import <FirebaseFirestore/FIRFirestoreSettings.h>
 
+#include <utility>
+
 #import "Firestore/Example/Tests/Util/FSTHelpers.h"
 #import "Firestore/Example/Tests/Util/FSTIntegrationTestCase.h"
 #import "Firestore/Source/Remote/FSTDatastore.h"
@@ -327,4 +330,74 @@ using firebase::firestore::model::SnapshotVersion;
   ]];
 }
 
+class MockCredentialsProvider : public firebase::firestore::auth::EmptyCredentialsProvider {
+ public:
+  MockCredentialsProvider() {
+    observed_states_ = [NSMutableArray new];
+  }
+
+  void GetToken(firebase::firestore::auth::TokenListener completion) override {
+    [observed_states_ addObject:@"GetToken"];
+    EmptyCredentialsProvider::GetToken(std::move(completion));
+  }
+
+  void InvalidateToken() override {
+    [observed_states_ addObject:@"InvalidateToken"];
+    EmptyCredentialsProvider::InvalidateToken();
+  }
+
+  NSMutableArray<NSString *> *observed_states() const {
+    return observed_states_;
+  }
+
+ private:
+  NSMutableArray<NSString *> *observed_states_;
+};
+
+- (void)testStreamRefreshesTokenUponExpiration {
+  MockCredentialsProvider credentials;
+  FSTDatastore *datastore = [[FSTDatastore alloc] initWithDatabaseInfo:&_databaseInfo
+                                                   workerDispatchQueue:_workerDispatchQueue
+                                                           credentials:&credentials];
+  FSTWatchStream *watchStream = [datastore createWatchStream];
+
+  [_delegate awaitNotificationFromBlock:^{
+    [watchStream startWithDelegate:_delegate];
+  }];
+
+  // Simulate callback from GRPC with an unauthenticated error -- this should invalidate the token.
+  NSError *unauthenticatedError = [NSError errorWithDomain:FIRFirestoreErrorDomain
+                                                      code:FIRFirestoreErrorCodeUnauthenticated
+                                                  userInfo:nil];
+  dispatch_async(_testQueue, ^{
+    [watchStream.callbackFilter writesFinishedWithError:unauthenticatedError];
+  });
+  // Drain the queue.
+  dispatch_sync(_testQueue, ^{
+                });
+
+  // Try reconnecting.
+  [_delegate awaitNotificationFromBlock:^{
+    [watchStream startWithDelegate:_delegate];
+  }];
+  // Simulate a different error -- token should not be invalidated this time.
+  NSError *unavailableError = [NSError errorWithDomain:FIRFirestoreErrorDomain
+                                                  code:FIRFirestoreErrorCodeUnavailable
+                                              userInfo:nil];
+  dispatch_async(_testQueue, ^{
+    [watchStream.callbackFilter writesFinishedWithError:unavailableError];
+  });
+  dispatch_sync(_testQueue, ^{
+                });
+
+  [_delegate awaitNotificationFromBlock:^{
+    [watchStream startWithDelegate:_delegate];
+  }];
+  dispatch_sync(_testQueue, ^{
+                });
+
+  NSArray<NSString *> *expected = @[ @"GetToken", @"InvalidateToken", @"GetToken", @"GetToken" ];
+  XCTAssertEqualObjects(credentials.observed_states(), expected);
+}
+
 @end
diff --git a/Firestore/Example/Tests/Remote/FSTDatastoreTests.mm b/Firestore/Example/Tests/Remote/FSTDatastoreTests.mm
index 6d6e912..9783e37 100644
--- a/Firestore/Example/Tests/Remote/FSTDatastoreTests.mm
+++ b/Firestore/Example/Tests/Remote/FSTDatastoreTests.mm
@@ -53,6 +53,12 @@
                               code:FIRFirestoreErrorCodeUnavailable
                           userInfo:nil];
   XCTAssertFalse([FSTDatastore isPermanentWriteError:error]);
+
+  // "unauthenticated" is considered a recoverable error due to expired token.
+  error = [NSError errorWithDomain:FIRFirestoreErrorDomain
+                              code:FIRFirestoreErrorCodeUnauthenticated
+                          userInfo:nil];
+  XCTAssertFalse([FSTDatastore isPermanentWriteError:error]);
 }
 
 @end