Middleware not found in registry even when it's there

[msolli]

I've created a minimal example to demonstrate this problem:
https://github.com/msolli/reitit-missing-middleware

I’m setting up coercion, but I’m running into an exception. According to the docs:

The coercion middleware are compiled againts a route. In the middleware compilation step the actual coercer implementations are constructed for the defined models. Also, the middleware doesn't mount itself if a route doesn't have :coercion and :parameters or :responses defined.

So I should be able to declare routes like this:

  [
   [""
    {:middleware [:app.middleware/coerce-request
                  :app.middleware/coerce-response
                  :app.middleware/coerce-exceptions
                  :app.middleware/defaults]}

    ["/" ::home-page]]
    ;; More routes here that actually have coercions...
  ])

I make sure to pass in a map for :reitit.middleware/registry that includes the referenced middlewares.

Still, when the routes are created and compiled, I get an exception claiming the middleware is not in the registry:

clojure.lang.ExceptionInfo: Middleware :app.middleware/coerce-request not found in registry.

Available middleware in registry:

|                                  :id |                                                                                                                                                                         :description |
|--------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|    :app.middleware/coerce-request | {:name :reitit.ring.coercion/coerce-request, :spec :reitit.spec/parameters, :compile #object[reitit.ring.coercion$fn__172563 0x194605f7 "reitit.ring.coercion$fn__172563@194605f7"]} |
|   :app.middleware/coerce-response |   {:name :reitit.ring.coercion/coerce-response, :spec :reitit.spec/responses, :compile #object[reitit.ring.coercion$fn__56703 0x36e4e57e "reitit.ring.coercion$fn__56703@36e4e57e"]} |
| :app.middleware/coerce-exceptions |                               {:name :reitit.ring.coercion/coerce-exceptions, :compile #object[reitit.ring.coercion$fn__56716 0x7a95f7d4 "reitit.ring.coercion$fn__56716@7a95f7d4"]} |
|          :app.middleware/defaults |                                               {:name :app.middleware/wrap-defaults, :wrap #object[app.middleware$fn__212347 0x6b916d5 "app.middleware$fn__212347@6b916d5"]} |

It fails when compiling the ::home-page route, which does not have any coercion. Hence the coerce-request compile function returns nil, which causes into-middleware to throw.

[ikitommi]

Finally had time to look for this. So, this happens:

1. the mw is looked from the registry
2. it is found and coerced into a Middleware, e.g. running it's :compile
3. the compile returns nil for the other route (the coercion only mounts if there is both :coercion and :parameters defined, see here

Fixed in master.

[ikitommi]

fix released as part of [metosin/reitit "0.3.0-SNAPSHOT"]