Add Cosmos db manual session token management #37027
Conversation
JoasE
changed the title
| /// any release. You should only use it directly in your code with extreme caution and knowing that | ||
| /// doing so can result in application failures when updating to a new Entity Framework Core release. | ||
| /// </summary> | ||
| public class SessionTokenStorage : ISessionTokenStorage |
There was a problem hiding this comment.
Wondering if this needs to be a wrapper and have an SessionTokenStorageInternal.
Also wondering about naming: CosmosSessionTokenStorage?
There was a problem hiding this comment.
I now think that this API might be somewhat clunky to use. Perhaps this should just implement IReadOnlyDictionary<string, string> and that's what GetSessionTokens returns. AddSessionTokens(IReadOnlyDictionary<string, string>) will merge in the passed values and that's when you'll check container names (when the tokens are set internally we know that the containers are correct). I think this will make the common case of just moving all tokens from one instance to another easier and since it's not a special type it would also be simpler to (de)serialize in the app. This also avoids the potential ambiguity of the API using the default container name.
There was a problem hiding this comment.
If this implements IReadOnlyDictionary then the values in the reference the user receives will change after using a query or savechanges. Preventing them from having to call GetSessionTokens multiple times, but it might be confusing that it doesn't return a snapshot. Thoughts on this?
| } | ||
|
|
||
| // @TODO: Is this the right place for this? | ||
| annotations.Add(CosmosAnnotationNames.ContainerNames, GetContainerNames(model)); |
There was a problem hiding this comment.
In SessionTokenStorage I want to check whether the container exists if a user is appending or adding a session token. It felt expensive to do GetContainerNames every DbContext instantiation, while I felt it could be a property of the model. However, I am not sure if annotations are the right way to add this data to the model for the cosmos provider. I am also not sure what would be the best place to calculate this metadata and set the annotation. Doing this this way fails CompiledModelCosmosTests and I am not sure if there is actually something wrong or the test should change and if so how.
There was a problem hiding this comment.
@AndriySvyryd or @roji Could you provide some guidance on this?
| /// any release. You should only use it directly in your code with extreme caution and knowing that | ||
| /// doing so can result in application failures when updating to a new Entity Framework Core release. | ||
| /// </summary> | ||
| protected virtual ISessionTokenStorage SessionTokenStorage => _sessionTokenStorage ??= Dependencies.Context.Database.GetSessionTokens(); |
This comment was marked as outdated.
This comment was marked as outdated.
Sorry, something went wrong.
| _queryLogger = cosmosQueryContext.QueryLogger; | ||
| _standAloneStateManager = standAloneStateManager; | ||
| _threadSafetyChecksEnabled = threadSafetyChecksEnabled; | ||
| _sessionTokenStorage = sessionTokenStorage; |
There was a problem hiding this comment.
This will contain the instance from when the query was compiled, which will be incorrect for all, but the first time it's executed. Instead, add this to CosmosQueryContext
| _currentDbContext = currentDbContext; | ||
| _cosmosClient = cosmosClient; | ||
|
|
||
| SessionTokenStorage = new SessionTokenStorage(_currentDbContext.Context); |
There was a problem hiding this comment.
Implement IResettableService on this type and clear the tokens from SessionTokenStorage on reset (when an instance is returned to the pool). You can keep the container names, since a particular instance would only be reused for the same model.
Register CosmosDatabaseWrapper as IResettableService
2 participants
Allows the user to retrieve session tokens from reads and writes done by a dbcontext and set session tokens to use for reads.
Adds a GetSessionTokens() extension method to DatabaseFacade which returns session tokens per container.
Adds a AppendSessionTokens() extension method to DatabaseFacade which allows appending session tokens per container.
Adds GetSessionToken() and AppendSessionToken() for the default container.
Adds option ManualSessionTokenManagementEnabled to CosmosDbContextOptionsBuilder
Implements: #36504