I have the following:
(ns commentz.client
(:require
[om.core :as om :include-macros true]
[om.dom :as dom :include-macros true]
[clojure.browser.repl]))
(def app-state
(atom
{:id "a"
:value "I am the greatest of comments!"
:user "1"
:anonymous false
:score 10
:children
[{:value "I am ok too."
:user "1"
:anonymous false
:score 4
:children
[{:value "I am the second greatest comment"
:user "2"
:anonymous false
:score 7
:children {}}]}
{:value "I like turtles"
:user "3"
:anonymous true
:score -3
:children {}}]}))
(defn header [app owner]
(dom/div #js {:className "header"}
(dom/div #js {:className "vote"}
(dom/div #js {:className "up"})
(dom/div #js {:className "down"}))
(dom/a #js {:className "username" :href (:user app)} (:user-name app))
(dom/div #js {:className "score"} (:score app))))
(defn footer [app owner]
(dom/div #js {:className "footer"}
(dom/a #js {:className "permalink" :href (str "#" (:id app))} "permalink")
(dom/a #js {:className "reply"} "reply")))
(defn comment [app owner]
(reify
om/IRender
(render [this]
(dom/div {:id (:id app) :className "comment"}
(header app owner)
(dom/div #js {:className "value"} (:value app))
(footer app owner)
(om/build-all comment (:children app))))))
(om/root comment app-state {:target (. js/document (getElementById "app"))})
The above code does succesfully compile, but I am not seeing anything recursive. Instead, I am seeing the following when I inspect with a browser.
10
I am the greatest of comments!
permalink reply
0 32374988
I think the 32374988 might be a object hash, not sure what the 0 is about. Anyway, my intent is too see all 4 comments show up, with some comment nested within others. At the moment I am getting only the root comment, plus some weird 0 32374988 where the recursively built comments should be. Any help is appreciated. Thank you.
(om/build-all) returns a seq. Try (apply dom/div nil ...).
(apply dom/div {:id (:id app) :className "comment"}
(header app owner)
(dom/div #js {:className "value"} (:value app))
(footer app owner)
(om/build-all comment (:children app))))))
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 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.
I'm trying to understand how to properly setup JavaFX to work with a Clojure project. By reading various sources this is what I've come up with:
This is project.clj:
(defproject cljfx "0.1.0-SNAPSHOT"
:description "FIXME: write description"
:url "http://example.com/FIXME"
:license {:name "Eclipse Public License"
:url "http://www.eclipse.org/legal/epl-v10.html"}
:dependencies [[org.clojure/clojure "1.8.0"]]
:resource-paths ["lib/jfxrt.jar"]
:main ^:skip-aot cljfx.core
:target-path "target/%s"
:profiles {:uberjar {:aot :all}})
I don't know if I should use :resource-paths or add JavaFX to the classpath via the :dependencies vector...
This is core.clj:
I've basically translated to Clojure an example from this tutorial:
http://docs.oracle.com/javafx/2/get_started/hello_world.htm
(ns cljfx.core
(:gen-class
:extends javafx.application.Application)
(:import
[javafx.application Application]
[javafx.stage Stage]
[javafx.scene Scene]
[javafx.scene.control Button]
[javafx.scene.layout StackPane]
[javafx.event ActionEvent EventHandler]))
(defn -main [& args]
(Application/launch cljfx.core args))
(defn button [text]
(doto (Button.)
(.setText (str "Say " text))
(.setOnAction (proxy [EventHandler] []
(handle [event]
(println text))))))
(defn -start [primaryStage]
(let [root (doto (StackPane.)
(-> (.getChildren)
(.add (button "Hello World!"))))]
(doto primaryStage
(.setScene (Scene. root 300 250))
(.show))))
This doesn't compile, and I don't know what I'm doing wrong... can you help me?
Here is the error:
http://pastebin.com/sYeK7MJd
There may be other problems, but the root problem in the pastebin log is:
Caused by: clojure.lang.ArityException: Wrong number of args (2) passed to: core/-start
When using gen-class and providing method implementations, every method needs to take the instance itself as the first parameter. The convention is to use "this":
(defn -start [this primaryStage]
Try that, and ensure that local instance method calls are applied to "this".
Not really a CL nor a Web programming expert, so may be I'm missing something really obvious: I try to set a session-value in page-1 and fetch the result in page-2. Nothing is displayed in page-2, though...
(ql:quickload "cl-who")
(ql:quickload "hunchentoot")
(defpackage :sessmin
(:use :cl :cl-who :hunchentoot))
(in-package :sessmin)
(defun start-server (port)
(start (make-instance 'easy-acceptor :port port)))
(setf (html-mode) :html5)
(define-easy-handler (page1 :uri "/page1") ()
(start-session)
(setf (session-value :sv) "testvalue")
(with-html-output-to-string
(*standard-output* nil :prologue t :indent t)
(:html :lang "en"
(:head
(:meta :charset "utf-8")
(:title "page1"))
(:body
(:p "Session Page 1")
(:p "Go to next page" (:a :href "page2" "here"))))))
(define-easy-handler (page2 :uri "/page2") ()
(with-html-output-to-string
(*standard-output* nil :prologue t :indent t)
(:html :lang "en"
(:head
(:meta :charset "utf-8")
(:title "page2"))
(:body
(:p "Session Page 2")
(:p "Session Page 2, value:" (session-value :sv))))))
(start-server 8080)
EDIT: Got the "("s wrong in my first version, still does not work after correction though...
Your problem is not that the session value is not set, but in your cl-who format.
(:p "Session Page 2, value:" (session-value :sv))
will not print the session value; the return value of session-value is simply ignored.
;; try this:
(:p "Session Page 2, value:" (str (session-value :sv)))
;; or, if you need to html-escape the value,
(:p "Session Page 2, value:" (esc (session-value :sv)))
Not a Hunchentoot expert, but I think you forgot to close :head.