internal static DocumentSnapshot ForMissingDocument(FirestoreDb db, string name, Timestamp readTime) => new DocumentSnapshot(db, name, null, readTime);
private DocumentSnapshot(FirestoreDb db, string resourceName, Document document, Timestamp readTime)
{
GaxPreconditions.CheckNotNull(db, nameof(db));
GaxPreconditions.CheckNotNull(resourceName, nameof(resourceName));
Reference = db.GetDocumentReferenceFromResourceName(resourceName);
Document = document;
CreateTime = Timestamp.FromProtoOrNull(document?.CreateTime);
UpdateTime = Timestamp.FromProtoOrNull(document?.UpdateTime);
ReadTime = readTime;
}
internal static DocumentSnapshot ForDocument(FirestoreDb db, Document document, Timestamp readTime) => new DocumentSnapshot(db, document.Name, document, readTime);
//
// CreateDocumentSnapshot(DocumentChange documentChange)
//
// Generate a DocumentSnapshot from a Document
private DocumentSnapshot CreateDocumentSnapshot(Document document)
{
//Creation of DocumentSnapshots is internal so we are very much cheating and using reflection to access them
var snapshotType = typeof(DocumentSnapshot);
var forDocument = snapshotType.GetMethod("ForDocument", BindingFlags.Static | BindingFlags.NonPublic);
//It's probably bad to use the current timestamp, but we don't seem to have access to the readTime in ListenResponse
DocumentSnapshot snapshot = null;
try
{
snapshot = forDocument.Invoke(null, new object[] { FirestoreDb, document, Timestamp.GetCurrentTimestamp() }) as DocumentSnapshot;
}
catch (Exception ex)
{
OnError(ex.ToString());
}
return(snapshot);
}
public async Task <WatchResponseResult> HandleResponseAsync(ListenResponse response, CancellationToken cancellationToken)
{
switch (response.ResponseTypeCase)
{
case ListenResponse.ResponseTypeOneofCase.TargetChange:
TargetChange change = response.TargetChange;
bool noTargetIds = change.TargetIds.Count == 0;
switch (change.TargetChangeType)
{
case NoChange:
if (noTargetIds && change.ReadTime != null && _current)
{
// This means everything is up-to-date, so emit the current set of docs as a snapshot,
// if there were changes.
await PushSnapshotAsync(Timestamp.FromProto(change.ReadTime), change.ResumeToken, cancellationToken).ConfigureAwait(false);
}
break;
case Add:
GaxPreconditions.CheckState(!noTargetIds && WatchStream.WatchTargetId == change.TargetIds[0], "Target ID must be 0x{0:x}", WatchStream.WatchTargetId);
break;
case Remove:
GaxPreconditions.CheckState(!noTargetIds && WatchStream.WatchTargetId == change.TargetIds[0], "Target ID must be 0x{0:x}", WatchStream.WatchTargetId);
// This may not be the right kind of exception to throw, but whatever we throw should be a permanent error. This is a reasonable starting point.
throw new InvalidOperationException("Server removed watch target");
case Current:
_current = true;
break;
case Reset:
ResetDocs();
return(WatchResponseResult.Continue);
default:
throw new InvalidOperationException($"Encountered invalid target change type: {change.Cause.Message}");
}
bool healthy = change.ResumeToken != null && (change.TargetIds.Count == 0 || change.TargetIds.Contains(WatchStream.WatchTargetId));
// Possibly tell the watch stream that it's now healthy (so reset backoff), or just continue.
return(healthy ? WatchResponseResult.StreamHealthy : WatchResponseResult.Continue);
case ListenResponse.ResponseTypeOneofCase.DocumentChange:
// No other targetIds can show up here, but we still need to see if the targetId was in the
// added list or removed list.
var changed = response.DocumentChange.TargetIds.Contains(WatchStream.WatchTargetId);
var removed = response.DocumentChange.RemovedTargetIds.Contains(WatchStream.WatchTargetId);
Document document = response.DocumentChange.Document;
DocumentReference docRef = CreateDocumentReference(document.Name);
if (changed && removed)
{
throw new InvalidOperationException("Server error: document was both changed and removed");
}
if (!changed && !removed)
{
// This is probably an error in the server, but we can follow protocol by just ignoring this response.
return(WatchResponseResult.Continue);
}
_changeMap[docRef] = changed ? document : null;
return(WatchResponseResult.Continue);
case ListenResponse.ResponseTypeOneofCase.DocumentDelete:
_changeMap[CreateDocumentReference(response.DocumentDelete.Document)] = null;
return(WatchResponseResult.Continue);
case ListenResponse.ResponseTypeOneofCase.DocumentRemove:
_changeMap[CreateDocumentReference(response.DocumentRemove.Document)] = null;
return(WatchResponseResult.Continue);
case ListenResponse.ResponseTypeOneofCase.Filter:
// TODO: Do we really want to create the change set itself, rather than just count? It seems a bit wasteful.
ChangeSet changeSet = ExtractChanges(default);
int currentSize = _documentSet.Count + changeSet.Adds.Count - changeSet.Deletes.Count;
// Reset the stream if we don't have the right number of documents.
if (response.Filter.Count != currentSize)
{
ResetDocs();
return(WatchResponseResult.ResetStream);
}
return(WatchResponseResult.Continue);
default:
throw new InvalidOperationException($"Encountered invalid listen response type: {response.ResponseTypeCase}");
}
}
/// <summary>
/// Creates a precondition that the document has the specified last update time.
/// </summary>
public static Precondition LastUpdated(Timestamp timestamp) =>
new Precondition(new V1Beta1.Precondition {
UpdateTime = timestamp.ToProto()
});
internal static WriteResult FromProto(V1Beta1.WriteResult result, wkt::Timestamp commitTime)
{
GaxPreconditions.CheckNotNull(result, nameof(result));
GaxPreconditions.CheckNotNull(commitTime, nameof(commitTime));
return(new WriteResult(Timestamp.FromProto(result.UpdateTime ?? commitTime)));
}
private WriteResult(Timestamp updateTime)
{
UpdateTime = updateTime;
}