WCF Data Services 5.5.0 has officially been released! The 5.5.0 release will be another NuGet-only release as we did not make any updates to the Visual Studio tooling.
What is in the release:
This release has two primary features: 1) significant enhancements to the URI parser and 2) public data source providers. In addition to the primary features, there are two secondary enhancements and over 40 bug fixes included with this release.
URI Parser
In the 5.2.0 release ODataLib provided a way to parse $filter and $orderby expressions into a metadata-bound abstract syntax tree (AST). In the 5.5.0 release we have updated the URI parser with support for most OData URIs. The newly introduced support for parsing $select and $expand is particularly notable. With the 5.5.0 release the URI Parser is mostly done. Future releases will focus on higher-order functions to further improve the developer experience.
Public Data Source Providers
In this release we have made the Entity Framework and Reflection data source providers public. This gives more control to service writers. There is more work planned in the future but the work we’ve completed allows some advanced scenarios which were not possible earlier. For example, a service writer can now make use of the Entity Framework query-caching feature by intercepting the request and parameterizing the LINQ query before handing it off to Entity Framework. (Note that parameterizing a LINQ query is not the same as parameterizing a SQL query; EF always does the latter and therefore there is no security implications to failing to parameterize a LINQ to Entities query, the only impact is performance related.)
While the potential unlocked with this release is limited, this is the first move in a direction which will unlock many previously unachievable scenarios with the built in providers.
Performance Improvements
We constantly strive to improve performance and reliability with every release. In this release, we have increased performance by double digit percentages for service authors that want to respond with JSON but are not able to (or don't want to) provide a data model to ODataLib.
Improved Developer Experience
In this release we have caught up with some missing IntelliSense guidance and we are uploading symbols and source to SymbolSource.org. We will upload symbols for many of our past releases as well.
Bug Fixes
In addition to the features above, we have included fixes for the following notable bugs:
- Fixes an issue where the reflection provider would not work properly if the generic parameter provided to DataService
was an interface - Fixes an issue where some system headers were not being set when a client called BuildingRequest
- Fixes an issue where setting InstanceContextMode to Single on DataService would result in cache result being returned for subsequent requests
- Fixes an issue where ODataLib would sometimes allow null to be written whether or not the expected type was nullable
- Fixes a regression in 5.4 where ODataLib started writing unnecessary type information in certain instances
- Fixes an issue where the WCF DS client would sometimes not dispose the response if the response had no content
- Improves a number of errors and error messages