I recently upgraded .net core 2.2 web api with Odata and Swagger to 3.1 following Microsoft’s recent endpoint routing support with OData 7.40. All was going great until I realised certain API endpoints were failing with “Object reference not set to an instance of an object. at Microsoft.AspNetCore.Mvc.Routing.ApiVersionMatcherPolicy”. On closer inspection the endpoints failing were all child resources. For example ../api/company/1 works fine ../api/company/1/staff and ../api/company/1/staff/1 were failing with
Decided to take the plunge and update a fairly sizeable WebAPI with OData and Swagger to .Net Core 3.1. Why the hell would you do this you may ask? Well to take advantage of 3.1’s endpoint routing and OData’s recent support for this with OData 7.40. Inspired by Hassan Habib’s blog entry on Microsoft Dev blogs and decided to go for it.
This one cropped up at work recently. As part of a project there was a requirement for an API to carry out a check as part of an update on an object to ensure that none of the object’s children met a certain criteria (I’m avoiding business context here).
Occasionally, on updating a plugin you might see the ‘Briefly unavailable for scheduled maintenance’ message in WordPress. This will be visible even if logged in as Admin. As part of the update process a “.maintenance” file is temporary created in the root folder of WordPress.
When creating an entity (with child entities) using POST with OData the response will only show the main Entity created. Child entities are ignored.