My middleware is throwing an error only for async requests, not sure why:
project.clj
(defproject asyncy "0.1.0-SNAPSHOT"
:description "FIXME: write description"
:dependencies [[org.clojure/clojure "1.9.0"]
[metosin/compojure-api "1.1.11"]
[org.clojure/core.async "0.3.442"]]
:ring {:handler asyncy.handler/app}
:uberjar-name "server.jar"
:profiles {:dev {:dependencies [[javax.servlet/javax.servlet-api "3.1.0"]]
:plugins [[lein-ring "0.12.0"]]}})
handler.clj
To make this even easier to talk about and diagnose, i've made a bare minimum version of the problem using the lein new compojure-api template
(ns asyncy.handler
(:require [compojure.api.sweet :refer :all]
[ring.util.http-response :refer :all]
[schema.core :as s]
[clojure.core.async :as async]))
(s/defschema Pizza
{:name s/Str
(s/optional-key :description) s/Str
:size (s/enum :L :M :S)
:origin {:country (s/enum :FI :PO)
:city s/Str}})
(def app
(api
{:async? true
:swagger
{:ui "/"
:spec "/swagger.json"
:data {:info {:title "Asyncy"
:description "Compojure Api example"}
:tags [{:name "api", :description "some apis"}]}}}
(context "/api" []
:tags ["api"]
:middleware [(fn [handler]
;; this sync-style handler always handles both sync and async requests
(fn ([request]
(clojure.pprint/pprint request)
(if (some-> request :params :x (= "1"))
(bad-request {:error true :message "one is the loneliest number that you'll ever do"})
;; this throws an error on async requests
(handler request)))
;; this async 3-arity handler is never called
([request b c]
(clojure.pprint/pprint ["never called, doesnt matter." request b c]))
))]
(GET "/plus" []
:return {:result Long}
:query-params [x :- Long, y :- Long]
:summary "adds two numbers together"
(ok {:result (+ x y)}))
(GET "/plus-async" []
:return {:result Long}
:query-params [x :- Long, y :- Long]
:summary "adds two numbers together"
(fn [request respond raise]
(respond (ok {:result (+ x y)}))))
)))
(handler request) in the middleware is what throws the error, for async requests only:
ERROR Wrong number of args (1) passed to: handler/fn--26289/fn--26301/fn--26303
clojure.lang.ArityException: Wrong number of args (1) passed to: handler/fn--26289/fn--26301/fn--26303
at clojure.lang.AFn.throwArity(AFn.java:429)
at clojure.lang.AFn.invoke(AFn.java:32)
at compojure.response$eval1960$fn__1961.invoke(response.clj:47)
at compojure.response$eval1882$fn__1883$G__1873__1890.invoke(response.clj:7)
at compojure.core$wrap_response$fn__3839.invoke(core.clj:158)
at compojure.core$pre_init$fn__3938.invoke(core.clj:328)
at compojure.api.coerce$body_coercer_middleware$fn__14642.invoke(coerce.clj:51)
at compojure.core$pre_init$fn__3940$fn__3943.invoke(core.clj:335)
at compojure.core$wrap_route_middleware$fn__3823.invoke(core.clj:127)
at compojure.core$wrap_route_info$fn__3828.invoke(core.clj:137)
at compojure.core$wrap_route_matches$fn__3832.invoke(core.clj:146)
at compojure.core$wrap_routes$fn__3950.invoke(core.clj:348)
at compojure.api.routes.Route.invoke(routes.clj:74)
at compojure.core$routing$fn__3847.invoke(core.clj:185)
at clojure.core$some.invokeStatic(core.clj:2693)
at clojure.core$some.invoke(core.clj:2684)
at compojure.core$routing.invokeStatic(core.clj:185)
at compojure.core$routing.doInvoke(core.clj:182)
at clojure.lang.RestFn.applyTo(RestFn.java:139)
at clojure.core$apply.invokeStatic(core.clj:659)
at clojure.core$apply.invoke(core.clj:652)
at compojure.core$routes$fn__3851.invoke(core.clj:192)
at asyncy.handler$fn__26289$fn__26290$fn__26291.invoke(handler.clj:32)
at compojure.core$routing$fn__3847.invoke(core.clj:185)
at clojure.core$some.invokeStatic(core.clj:2693)
at clojure.core$some.invoke(core.clj:2684)
at compojure.core$routing.invokeStatic(core.clj:185)
at compojure.core$routing.doInvoke(core.clj:182)
at clojure.lang.RestFn.applyTo(RestFn.java:139)
at clojure.core$apply.invokeStatic(core.clj:659)
at clojure.core$apply.invoke(core.clj:652)
at compojure.core$routes$fn__3851.invoke(core.clj:192)
at compojure.core$make_context$handler__3919.invoke(core.clj:285)
at compojure.core$make_context$fn__3921.invoke(core.clj:293)
at compojure.api.routes.Route.invoke(routes.clj:74)
at compojure.api.core$handle$fn__14853.invoke(core.clj:8)
at clojure.core$some.invokeStatic(core.clj:2693)
at clojure.core$some.invoke(core.clj:2684)
at compojure.api.core$handle.invokeStatic(core.clj:8)
at compojure.api.core$handle.invoke(core.clj:7)
at clojure.core$partial$fn__5561.invoke(core.clj:2616)
at compojure.api.routes.Route.invoke(routes.clj:74)
at ring.swagger.middleware$wrap_swagger_data$fn__14015.invoke(middleware.clj:35)
at ring.middleware.http_response$wrap_http_response$fn__8034.invoke(http_response.clj:19)
at ring.swagger.middleware$wrap_swagger_data$fn__14015.invoke(middleware.clj:35)
at compojure.api.middleware$wrap_options$fn__14077.invoke(middleware.clj:74)
at ring.middleware.format_params$wrap_format_params$fn__7105.invoke(format_params.clj:119)
at ring.middleware.format_params$wrap_format_params$fn__7105.invoke(format_params.clj:119)
at ring.middleware.format_params$wrap_format_params$fn__7105.invoke(format_params.clj:119)
at ring.middleware.format_params$wrap_format_params$fn__7105.invoke(format_params.clj:119)
at ring.middleware.format_params$wrap_format_params$fn__7105.invoke(format_params.clj:119)
at compojure.api.middleware$wrap_exceptions$fn__14067.invoke(middleware.clj:43)
at ring.middleware.format_response$wrap_format_response$fn__7930.invoke(format_response.clj:194)
at ring.middleware.keyword_params$wrap_keyword_params$fn__8076.invoke(keyword_params.clj:36)
at ring.middleware.nested_params$wrap_nested_params$fn__8134.invoke(nested_params.clj:89)
at ring.middleware.params$wrap_params$fn__4079.invoke(params.clj:67)
at compojure.api.middleware$wrap_options$fn__14077.invoke(middleware.clj:74)
at compojure.api.routes.Route.invoke(routes.clj:74)
at clojure.lang.Var.invoke(Var.java:381)
at ring.middleware.reload$wrap_reload$fn__1829.invoke(reload.clj:39)
at ring.middleware.stacktrace$wrap_stacktrace_log$fn__1211.invoke(stacktrace.clj:26)
at ring.middleware.stacktrace$wrap_stacktrace_web$fn__1277.invoke(stacktrace.clj:96)
at ring.adapter.jetty$proxy_handler$fn__487.invoke(jetty.clj:25)
at ring.adapter.jetty.proxy$org.eclipse.jetty.server.handler.AbstractHandler$ff19274a.handle(Unknown Source)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
at org.eclipse.jetty.server.Server.handle(Server.java:499)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:258)
at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:544)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
at java.lang.Thread.run(Thread.java:748)
How does one do middleware with async compojure-api? Feel like i'm just totally off on how to implement this.
Related
I'm trying to build a simple webapp using clojure/clojurescript for backend/frontend respectively. I'm having trouble establishing communication between the two of them via http requests, I feel like my issue is in the frontend but I'm not completly sure.
Here's my back end code:
(ns example.handler
(:require [compojure.core :refer :all]
[compojure.route :as route]
[clojure.data.json :as json]
[clj-http.client :as client]
[datomic.api :as d]
[ring.util.response :as resp]
[ring.middleware.defaults :refer [wrap-defaults site-defaults]])
(:use [hiccup.core]))
;; Route
(defroutes app-routes
(GET "/info" [] (json/write-str {:data (some-function x)})))
So far so good, when I go to localhost:3000/info I see on the browser something like {"data":10} which is the expected result. I read that using cljs-http is the standard for clojurescript requests, so I followed the simple example on the repo and my code looks like this:
(ns example-cljs.core
(:require [reagent.core :as reagent :refer [atom]]
[clojure.core.async :as async]
[cljs-http.client :as http]))
(def example-req (atom nil))
(defn get-data []
(async/go
(let [response (async/<! (http/get "localhost:3000/info"))]
(reset! example-req response))))
But the response is just {:status 0, :success true, :body "", :headers {}, :trace-redirects ["localhost:3000/info" "localhost:3000/info"], :error-code :no-error, :error-text ""}
I feel like this is such a rookie mistake but I just can't find where it is.
Thanks for any help or hint.
So, after a some research I found to this tutorial so I'm just gonna copy-paste what I found that solved the issue:
Add ring-cors dependency to hello-compojure in project.clj.
:dependencies [[org.clojure/clojure "1.10.0"]
[org.clojure/tools.nrepl "0.2.13"]
[com.datomic/datomic-pro "0.9.6024"]
[org.clojure/data.json "0.2.6"]
[ring-cors "0.1.13"]
[compojure "1.6.1"]
[hiccup "1.0.5"]
[ring/ring-defaults "0.3.2"]]
Require it in handler.clj in the server.
(ns hello-compojure.handler
(:require [compojure.core :refer :all]
[compojure.route :as route]
[datomic.api :as d]
[clojure.data.json :as json]
[ring.util.response :as resp]
[ring.middleware.cors :refer [wrap-cors]]
[ring.middleware.defaults :refer [wrap-defaults site-defaults]])
And finally replace app definition in handler.clj with this :
(def app
(-> app-routes
(wrap-cors :access-control-allow-origin [#".*"]
:access-control-allow-methods [:post :get]
:access-control-allow-credentials "true"
:access-control-allow-headers "Content-Type, Accept, Authorization, Authentication, If-Match, If-None-Match, If-Modified-Since, If-Unmodified-Since")
(wrap-defaults (assoc-in site-defaults [:security :anti-forgery] false))))
I have the following simple server in Clojure using Compojure (which is some flavor of the ring pattern). Everything was working fine in development, and now that I'm in prod I can't get CORS to work for the life of me - I have a wrap-preflight function which seems to work fine, but I keep getting CORS errors in terminal and neither the post or get requests for my comment system work. I am totally lost and very frustrated, I've asked around and no one else seems to know.
Here is the main core.clj code - If anyone has any ideas please let me know. You can see the errors live at thedailyblech.com (not an advert, but maybe it will help debug).
Thank you!
(ns clojure-play.core
(:use org.httpkit.server
[compojure.core :refer :all]
[compojure.route :as route]
[clojure.data.json :as json]
[clojure.tools.logging :only [info]]
[clojure-play.routes :as routes]
[ring.middleware.json :only [wrap-json-body]]
[ring.middleware.cors :refer [wrap-cors]])
(:require [monger.core :as mg]
[monger.collection :as mc]
[clojure.edn :as edn]
[clojure.java.io :as io]
[compojure.handler :as handler])
(:import [org.bson.types ObjectId]
[com.mongodb DB WriteConcern])
(:gen-class))
(println "in the beginning was the command line...")
(defonce channels (atom #{}))
(defn connect! [channel]
(info "channel open")
(swap! channels conj channel))
(defn notify-clients [msg]
(doseq [channel #channels]
(send! channel msg)))
(defn disconnect! [channel status]
(info "channel closed:" status)
(swap! channels #(remove #{channel} %)))
(defn ws-handler [request]
(with-channel request channel
(connect! channel)
(on-close channel (partial disconnect! channel))
(on-receive channel #(notify-clients %))))
(defn my-routes [db]
(routes
(GET "/foo" [] "Hello Foo")
(GET "/bar" [] "Hello Bar")
(GET "/json_example/:name" [] routes/json_example)
(GET "/json_example" [] routes/json_example)
(POST "/email" [] routes/post_email)
(POST "/write_comment" [] (fn [req] (routes/write_comment req db)))
(POST "/update_comment" [] (fn [req] (routes/update_comment req db)))
(GET "/read_comments/:path" [path] (fn [req] (routes/read_comments req db path)))
(GET "/read_comments/:path1/:path2" [path1 path2] (fn [req] (routes/read_comments req db (str path1 "/" path2))))
(GET "/ws" [] ws-handler)))
(defn connectDB []
(defonce connection
(let
[uri "mongodb://somemlabthingy"
{:keys [conn db]} (mg/connect-via-uri uri)]
{:conn conn
:db db}))
{:db (:db connection)
:conn (:conn connection)})
(def cors-headers
"Generic CORS headers"
{"Access-Control-Allow-Origin" "*"
"Access-Control-Allow-Headers" "*"
"Access-Control-Allow-Methods" "GET POST OPTIONS DELETE PUT"})
(defn preflight?
"Returns true if the request is a preflight request"
[request]
(= (request :request-method) :options))
(defn -main
"this is main"
[& args]
(println "hello there main")
(def db (get (connectDB) :db))
(println (read-string (slurp (io/resource "environment/config.edn"))))
(defn wrap-preflight [handler]
(fn [request]
(do
(println "inside wrap-preflight")
(println "value of request")
(println request)
(println "value of handler")
(println handler)
(if (preflight? request)
{:status 200
:headers cors-headers
:body "preflight complete"}
(handler request)))))
(run-server
(wrap-preflight
(wrap-cors
(wrap-json-body
(my-routes db)
{:keywords? true :bigdecimals? true})
:access-control-allow-origin [#"http://www.thedailyblech.com"]
:access-control-allow-methods [:get :put :post :delete :options]
:access-control-allow-headers ["Origin" "X-Requested-With"
"Content-Type" "Accept"]))
{:port 4000}))
The CORS middleware handles the preflight stuff automatically -- you do not need separate middleware for it, nor do you need to produce your own headers etc.
You have it wrapping the routes which is correct -- so CORS-checking happens first, then routing. You should remove your custom preflight middleware and it should work at that point.
We use wrap-cors at work and the only complication we hit was in allowing enough headers (some inserted by production infrastructure, like load balancers). We ended up with this:
:access-control-allow-headers #{"accept"
"accept-encoding"
"accept-language"
"authorization"
"content-type"
"origin"}
For what it's worth, here's what we have for methods:
:access-control-allow-methods [:delete :get
:patch :post :put]
(you do not need :options in there)
After digging around for hours, I found this to be super helpful on an issues post on the ring-cors github, for which documentation was severely lacking.
Using the linked gist, I was able to get past the CORS issues:
; Copied from linked gist
(def cors-headers
"Generic CORS headers"
{"Access-Control-Allow-Origin" "*"
"Access-Control-Allow-Headers" "*"
"Access-Control-Allow-Methods" "GET"})
(defn preflight?
"Returns true if the request is a preflight request"
[request]
(= (request :request-method) :options))
(defn all-cors
"Allow requests from all origins - also check preflight"
[handler]
(fn [request]
(if (preflight? request)
{:status 200
:headers cors-headers
:body "preflight complete"}
(let [response (handler request)]
(update-in response [:headers]
merge cors-headers )))))
; my -main
(defn -main
"Main entry point"
[& args]
(let [port (Integer/parseInt (or (System/getenv "PORT") "8081"))]
(server/run-server
(all-cors
(wrap-defaults #'app-routes site-defaults))
{:port port})
(println "Running on" port)))
This finally allowed me to see the headers properly set in Chrome dev tools and also got rid of the warning on my React front-end.
Access-Control-Allow-Headers: *
Access-Control-Allow-Methods: GET
Access-Control-Allow-Origin: *
Might be worth trying and adding an explicit
(OPTIONS "/*" req handle-preflight)
route to your Compojure routes - in my case that's what made it work.
(RING-MIDDLEWARE-CORS/wrap-cors
:access-control-allow-credentials "true"
:access-control-allow-origin [#".*"]
:access-control-allow-headers #{"accept"
"accept-encoding"
"accept-language"
"authorization"
"content-type"
"origin"}
:access-control-allow-methods [:get :put :post :delete :options])
My web client (written in cljs) connects to backend (written in clj) which needs to make a few third party API calls. It has to be done on the server and then the result should be transformed in a specific way and sent back to the client.
Here's my handler for one of the urls
(defn get-orders [req]
(let [{:keys [sig uri]} (api-signature :get-orders)]
(client/get uri
{:async? true}
(fn [response] {:body "something"})
(fn [exception] {:body "error"}))))
Instead of returning {:body "something"}, it is returning the following error:
No implementation of method: :render of protocol: #'compojure.response/Renderable found for class: org.apache.http.impl.nio.client.FutureWrapper
What am I doing wrong?
When you specify {:async? true}, clj-http.client/get will return a future which is a FutureWrapper in the error message you got.
So if you don't need async, don't use it. This is an example of a synchronous ring handler which calls a third-party url and returns the response that got back.
(defn handler [request]
(response {:result (client/get "http://example.com")}))
If you really need async, use async version of ring handler.
(defn handler [request respond raise]
(client/get "http://example.com"
{:async? true}
(fn [response] (respond {:body "something"}))
(fn [exception] (raise {:body "error"}))))
Don't forget to config webserver adapter to use the async handler. For example, for Jetty, set :async? flag to true like so
(jetty/run-jetty app {:port 4000 :async? true :join? false})
If you want to concurrently call to multiple third-party urls and return once to web client, use promise to help
(defn handler [request]
(let [result1 (promise)
result2 (promise)]
(client/get "http://example.com/"
{:async? true}
(fn [response] (deliver result1 {:success true :body "something"}))
(fn [exception] (deliver result1 {:success false :body "error"})))
(client/get "http://example.com/"
{:async? true}
(fn [response] (deliver result2 {:success true :body "something"}))
(fn [exception] (deliver result2 {:success false :body "error"})))
(cond
(and (:success #result1)
(:success #result2))
(response {:result1 (:body #result1)
:result2 (:body #result2)})
(not (:success #result1))
(throw (ex-info "fail1" (:body #result1)))
(not (:success #result2))
(throw (ex-info "fail2" (:body #result2))))))
I'm trying to create a file preloader within ClojureScript. My idea was a pattern like this:
(def urls (atom[]))
(def loaded-resources (atom []))
(def all-resources (promise))
(defn loading-callback []
(if (= (count urls) (count loaded-resources))
(deliver all-resources loaded-resources)))
;; fill urls array
;; start ajax-loading with loading-callback on success
So my main function could go on until it would require the resources and then wait for them, which works well in Clojure.
Unfortunately, promises don't exist in ClojureScript, so how can I work around that issue? There's promesa bringing promises to CLJS based on core.async channels, but it only allows future-like promises that wait for a single function to execute which won't suffice my needs (at least in the way I've been thinking about it yesterday...).
Any suggestions to solve this issue? Maybe use a completely different pattern? I want to keep the code as simple as possible to convince people in my team to try out CLJ/S.
EDIT:
After Alan's second idea:
(def urls (atom[]))
(def loaded-resources (atom []))
(defn loading-callback [data]
(swap! loaded-resources conj data))
(defn load! [post-loading-fn]
(add-watch loaded-resources :watch-loading
(fn [_ _ _ cur]
(if (= (count cur) (count #urls)) (post-loading-fn))))
;; init ajax loading
)
(defn init []
;; fill urls array
(load! main))
(main []
(do-terrific-stuff #loaded-resources))
Meanwhile I had tried to use core.async
(def urls (atom []))
(def loaded-resources (atom []))
(def resource-chan (chan))
(defn loading-callback [data]
(go (>! resource-chan data)))
;; fill url array from main
(load! []
;; init ajax loading
(go-loop []
(when-not (= (count #loaded-resources) (count #urls))
(swap! loaded-resources conj (<! resource-chan))
(recur)))
Not sure which version is better.
I can think of 2 approaches.
Change all-resources to another atom, initialized at nil. Poll it 2x-5x/sec until it is not nil and has the "delivered" result.
Use add-watch to register a callback function to execute when the value is changed. This takes the place of blocking until the value is delivered. It is described here: http://clojuredocs.org/clojure.core/add-watch
They show a good example:
(def a (atom {}))
(add-watch a :watcher
(fn [key atom old-state new-state]
(prn "-- Atom Changed --")
(prn "key" key)
(prn "atom" atom)
(prn "old-state" old-state)
(prn "new-state" new-state)))
(reset! a {:foo "bar"})
;; "-- Atom Changed --"
;; "key" :watcher
;; "atom" #<Atom#4b020acf: {:foo "bar"}>
;; "old-state" {}
;; "new-state" {:foo "bar"}
;; {:foo "bar"}
Assuming your load resource function returns a channel (like cljs-http/get).
In clj, all you need to do is hold on to them to do a "wait-all".
(let [cs (doall (map load-resource urls)) ;; initiate the get
... ;; other initialisation
res (map <!! cs)] ;; wait-all for the resources
(do-other-things res))
In cljs, you can accumulate the responses before you continue:
(go
(let [res (atom [])]
(doseq [c cs]
(swap! res conj (<! c)))
(do-other-things #res)))
JavaScript is a single threaded environment so there is no blocking wait.
If you wish to request multiple resources and continue iff they have all been served, I do recommend using core.async and especially pipeline-async. It has a knob to finetune the parallelism of asynchronous requests. Here is idiomatic ClojureScript code to achieve what you want:
(ns example.core
(:require [cljs.core.async :refer [chan take! put! pipeline-async]
:as async]))
(defn load-resources [urls on-resources]
(let [urls-ch (chan (count urls))
resources-ch (chan)]
;; Create pipeline:
(pipeline-async 10 ;; have at most 10 requests in flight at
;; the same time, finetune as desired
resources-ch
(fn [url done-ch]
;; Pseudo code:
(request-resource
url
(fn [loaded-resource]
(put! done-ch loaded-resource))))
urls-ch)
;; Eagerly aggregate result until results-ch closes, then call back:
(take! (async/into [] resources-ch) on-resources)
;; Start the party by putting all urls onto urls-ch
;; and then close it:
(async/onto-chan urls-ch urls)))
While using Clojure proxies, fns passed to proxy should override existing methods or are they called in conjunction with super.method()?
In the following code, RequestHandler.get() is invoked along with the proxy get [].
;see: http://github.com/paulosuzart/JTornado
(ns org.ctornadoweb)
(import '(org.jtornadoweb Web$RequestHandler))
(import '(org.jtornadoweb HttpServer Web$Application))
(let [myHandler (proxy [Web$RequestHandler] []
(get []
(.write "Hi CLJ"))
(post []
(.write "POST")))]
(.listen
(HttpServer.
(.add (Web$Application.) "/" (class myHandler))
false nil false) 8089))
The same happens to the compiled/inheritance version:
; Starts a JTornado HTTP Server and a sample RequestHandler.
; Bit verbose due to compilation directives. Recommendation is to generate
; a set of macros to hide this.
(ns org.ctornadoweb
; Compiled and implements a static main method to start the server
(:import (org.jtornadoweb HttpServer)
(org.jtornadoweb.Web$Application)
(org.jtornadoweb.Web$RequestHandler))
(:gen-class :prefix "server-"))
(gen-class
:name org.ctornadoweb.MyHandler
:extends org.jtornadoweb.Web$RequestHandler
:prefix "do")
(defn do-get [this]
"Handles the HTTP GET method"
(.write "hello clojure"))
(defn do-post [this]
"Handles the HTTP POST method"
(.write (.getArgument "name" "default" false)))
(defn server-main []
"main method"
(.listen
(org.jtornadoweb.HttpServer.
(.add (org.jtornadoweb.Web$Application.) "/" org.ctornadoweb.MyHandler)
false nil false) 8089))
;use (compile 'org.ctornadoweb)
The trace shows the proxy get being invoked and then the super.get, what throws (by default) an exception.
HTTP 405: Method Not Allowed
at org.jtornadoweb.Web$RequestHandler.get(Web.java:72)
at org.ctornadoweb.proxy$org.jtornadoweb.Web$RequestHandler$0.get(Unknown Source)
I tried to find some words about the actual behavior of Clojure Proxies. Can someone give this help?
No, the super method will not be called automatically, though you can explicitly call it with proxy-super.
The following test case shows things working as they should:
user=> (def foo
(proxy [java.util.ArrayList] []
(clear [] (println "not clearing"))))
#'user/foo
user=> (.size foo)
0
user=> (.add foo "hi")
true
user=> (.add foo "bye")
true
user=> (.size foo)
2
user=> (.clear foo)
not clearing
nil
user=> (.size foo)
2
If super.clear() were getting called, the size would show as 0.