Support for Azure Cosmos DB Azure Table Api?

[juvis]

Hi Will Streamstone support using Azure Cosmos DB with Azure Table Api anytime soon? I'm working on a proof of concept using Streamstone and was hoping that it was possible to use Streamstone with Cosmos DB since Streamstone now uses the Microsoft.Azure.Cosmos.Table api. I tried to run the example scenarios using a connection string to a Cosmos DB with Azure Table Api, but I get the error listed below:

Microsoft.Azure.Cosmos.Table.StorageException HResult=0x80131500 Message=Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.String' because the type requires a JSON primitive value (e.g. string, number, boolean, null) to deserialize correctly. To fix this error either change the JSON to a JSON primitive value (e.g. string, number, boolean, null) or change the deserialized type so that it is a normal .NET type (e.g. not a primitive type like integer, not a collection type like an array or List) that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. Path 'Id.$t', line 1, position 45. Source=Microsoft.Azure.Cosmos.Table StackTrace: at Microsoft.Azure.Cosmos.Table.Extensions.TableExtensionOperationHelper.d1`1.MoveNext() at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at Microsoft.Azure.Cosmos.Table.Extensions.TableExtensionRetryPolicy.d21.MoveNext() at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.ConfiguredTaskAwaitable1.ConfiguredTaskAwaiter.GetResult() at Streamstone.Stream.WriteOperation.d6.MoveNext() in C:\Development\Streamstone\Source\Streamstone\Stream.Operations.cs:line 96 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at Streamstone.Stream.WriteOperation.Batch.Handle(StorageException exception) in C:\Development\Streamstone\Source\Streamstone\Stream.Operations.cs:line 241 at Streamstone.Stream.WriteOperation.d6.MoveNext() in C:\Development\Streamstone\Source\Streamstone\Stream.Operations.cs:line 100 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() at Example.Scenarios.S04_Write_to_stream.d1.MoveNext() in C:\Development\Streamstone\Source\Example\Scenarios\S04_Write_to_stream.cs:line 33 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Example.Scenarios.S04_Write_to_stream.d0.MoveNext() in C:\Development\Streamstone\Source\Example\Scenarios\S04_Write_to_stream.cs:line 18 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Example.Program.

d__0.MoveNext() in C:\Development\Streamstone\Source\Example\Program.cs:line 39 at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Example.Program.

(String[] args)

Inner Exception 1: JsonSerializationException: Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.String' because the type requires a JSON primitive value (e.g. string, number, boolean, null) to deserialize correctly. To fix this error either change the JSON to a JSON primitive value (e.g. string, number, boolean, null) or change the deserialized type so that it is a normal .NET type (e.g. not a primitive type like integer, not a collection type like an array or List) that can be deserialized from a JSON object. JsonObjectAttribute can also be added to the type to force it to deserialize from a JSON object. Path 'Id.$t', line 1, position 45.

[gianlucacambareri]

Check if you have a field or property named "Id", i had same issue, but after raname this field all works fine.

[juvis]

That did the trick! Thanks!

[colgreen]

FYI I get the same json serialization error (as discussed above) when running the streamstone unit tests against CosmosDB Table storage... because the test EventData object/type has an Id property.

[yevhen]

@colgreen I don't get it. What's so special about this field? It's just a custom column name. Are there any restrictions on column names in CosmosDB?

[colgreen]

It's interesting that there is a deserialization exception when writing a record. My first thought is that the issue is in the Cosmos Table API code somewhere, i.e., it seems to have a problem deserializing the EventId type when writing a record. Honestly though, I was just playing with the different storage options, and thought you might be interested to know that the unit tests failed in this way when pointing to CosmosDB table storage. I used a connection string like so:

AccountName=Foo;TableEndpoint=https://localhost:8081/;AccountKey=<key here>

(That is pointing at an instance of the CosmosDB Emulator running on localhost)

Presumably a slightly different code path is used when using Azure Table Storage, that doesn't do that deserialization step(?)