Prepend function to every route request in yada - clojure

Question

currently i am playing with Yada as web lib. Now i want to execute some function before a route is hit.
Approaches I have tested:
- wrap the current resource as sub-resource, but then the swagger-doc doesn't find the resource
- using an prepend-interceptor, but the docu is not complete at this point at i got errors
My code:
(ns all-mighty.namespace
(:require [yada.yada :refer [handler listener resource as-resource]]
[yada.swagger :refer [swaggered]])
(defn resources []
[""
(swaggered
[""
[
(cool-route)
]]
{:info {:title "Hello You!"
:version "1.0"
:description "It's something"}
:basePath ""}
)])
(defn cool-route []
["/cool" (resource {
:description "Returns somethign cool"
:produces "application/json"
:methods {:get {:response cool-response}}}
)])
(defn cool-response [ctx]
(-> (:response ctx)
(assoc :status 200)
(assoc :body {:state :up}))
Yeah, I'll refactor the resources latter ;-)
Does someone has an idea?

Answer 1

The way I'm using append-interceptor:
(ns all-mighty.namespace
(:require
[yada.handler :refer [append-interceptor]]
[yada.interceptors :as i]
[yada.swagger :refer [swaggered]]
[yada.yada :refer [handler listener resource as-resource]]))
(defn cool-response [ctx]
{:state :up
:my/value (get ctx :my/value)})
(defn my-cool-interceptor [ctx]
(assoc ctx :my/value 10))
(defn my-cool-resource
[model]
(-> model
;; you have to provide an interception chain, here we use the default one
(assoc :interceptor-chain yada.yada/default-interceptor-chain)
resource
;; here we append our interceptor after the request body has been processed
(append-interceptor i/process-request-body my-cool-interceptor)))
(defn cool-route []
["/cool" (my-cool-resource {:description "Returns somethign cool"
:produces "application/json"
:methods {:get {:response cool-response}}})])
(defn routes []
[""
(swaggered
[""
[
(cool-route)
]]
{:info {:title "Hello You!"
:version "1.0"
:description "It's something"}
:basePath ""}
)])
(comment
(def l (listener (routes) {:port 1337}))
((:close l))
)
So for every resource under /cool you can use the my-cool-resource function to automatically add the desired interceptor.