[WIP] error renderers for different exception types

[NullVoxPopuli]

Currently, this doesn't work.

I guess I'm having a hard time figuring out where exactly the exceptions are caught and rendered as json

[joukevandermaas]

We definitely don't want to pull in Entity Framework as a reference. Why do you think we need this?

[NullVoxPopuli]

For thee executions?

[joukevandermaas]

What is the status of this PR?

[NullVoxPopuli]

I think there need to be some decisions around how extensions to Saule happen -- how to determine what renders an Exception, etc. It doesn't make sense to depend on EF in Saule in order to render EF errors, but it should be super straight forward to write on EFErrorRenderer or something like that, ya know?

[joukevandermaas]

I agree, there should be an extension point for this. It should likely be some interface people can implement and pass to Saule using the configuration object (similar to the URL builder). The interface should probably look something like this:

public interface ErrorRenderer 
{
    IEnumerable<JsonApiError> Render(object error);
}

where JsonApiError is a class that has all the error fields as described in the spec.

[NullVoxPopuli]

I like that. How would saule know to use a custom renderer?

[joukevandermaas]

Same as the URL builder; if the consumer supplies one, Saule will use it. When people build their own, they can derive from a default implementation and only override what they are actually customizing.

[joukevandermaas]

@NullVoxPopuli I'm closing this for now. Feel free to open a new PR with the changes we discussed against the current master branch.