OwinFeatureCollection: regression

[borgdylan]

After some recent changes in the hosting pipeline, the OwinFeatureCollection is no longer handling requests (requests do not even get read by the request pipeline). If I populate a FeatureCollection using an OwinFeatureCollection, the requests gets handled by the request pipeline but the response never surfaces out to the client.

[borgdylan]

After further investigation, the failures are happening as the setter is throwing a NotSupportedException. Certain features like the one for service providers, send file and request cookies are being set triggering the exception. If one removes the throw statement, nothing is fixed and the same client side behaviour persists.

[Tratcher]

Stack trace?

[borgdylan]

The method in question is the indexer's setter. Will add a stack trace later.

[davidfowl]

@borgdylan I'm interested in what changed that started to cause these problems.

[Tratcher]

aspnet/Hosting@435215b

This I bet. The context factory assumed the incoming feature collection was read-only, so it wrapped it in mutable collection. That wrapper was dropped in the last change, so it sounds like you're getting a notsupportedexception trying to call Set on a read-only feature collection.

Sent from my Windows Phone

---

From: David Fowlermailto:[email protected]
Sent: ‎2/‎28/‎2015 10:37 PM
To: aspnet/HttpAbstractionsmailto:[email protected]
Cc: Chris Rmailto:[email protected]
Subject: Re: [HttpAbstractions] OwinFeatureCollection: regression (#207)

@borgdylan I'm interested in what changed that started to cause these problems.

---

Reply to this email directly or view it on GitHub:
#207 (comment)

[davidfowl]

Ah, good catch.

[davidfowl]

@Praburaj Can you look at this? It's a regression caused by the code changes we made as a result of the API review. Add a test for it as well.

[borgdylan]

@davidfowl I agree with @Tratcher that this started to occur with IFeatureCollection being needed instead of an env object in the request handling delegate.

@Tratcher Wrapping inside a mutable feature collection solves the exception issue as I have tried it. But the response body still does not get sent back to the client side.

[borgdylan]

As an aside, Kestrel uses the mutable FeatureCollection directly. With that technique requests work OK. However I do get SignalR errors with respect to invalid delegate instructions.

[Praburaj]

@borgdylan @Tratcher @davidfowl - I'll have a look at this today and add a test as well.

[Praburaj]

@borgdylan what's the best way to reproduce this issue?

[Praburaj]

I tried running a couple of OWIN based entropy samples and they seem to run fine.

[borgdylan]

i have an updates server factory for nowin. Ill put it on github and you can try with it. It is what I am using.

[borgdylan]

https://github.com/borgdylan/nowinfactory

[Praburaj]

@borgdylan these changes already look to be in https://github.com/aspnet/Entropy/tree/dev/samples/Owin.Nowin.HelloWorld sample. This app seems to run fine. Does it require more than this to reproduce this issue?

[borgdylan]

My code is similar but has a logger for exceptions. Without that logger, the code will fail but the exception will be silently hidden.

[Praburaj]

@borgdylan Thanks. Got it.

Sent out a PR. aspnet/Hosting#174

[Praburaj]

merged the fix aspnet/Hosting@fde3b0d