ring response downloads index.html instead of rendering it - clojure

I have an index.html located in resources/public/index.html and have defined the following routes (application is split up more than this, just making the code concise):
(ns example.example
(:require [compojure.route :as route]))
(defroutes routes
(GET "/" [] (resource-response "index.html" {:root "public"} "text/html")))
(defroutes application-routes
routes
(route/resources "/")
(route/not-found (resource-response "index.html" {:root "public"} "text/html")))
(def application
(wrap-defaults application-routes site-defaults))
However, when I go to localhost:8090/ it downloads the html file instead of rendering it.
If I go to localhost:8090/index.html it renders the file properly so I assumed my routing is incorrect somehow but after looking at examples I am not too sure why.

This is exactly the same issue with this question.
You need to create a middleware to update your request:
(defn wrap-dir-index [handler]
(fn [req]
(handler
(update-in req [:uri]
#(if (= "/" %) "/index.html" %)))))
And then wrap your routes:
(def app
(wrap-dir-index (wrap-defaults app-routes site-defaults)))
Complete handler.clj.

Use this:
(:require [clojure.java.io :as io]
[ring.middleware.resource :as resource])
(defroutes routes
(GET "/" []
(io/resource "index.html")))
Also use middleware for resource wrapping
(resource/wrap-resource "/public")

Related

updated atom value not used in compojure route

I have a (routes (route/not-found)) definition with value derived from an (atom). Though I've updated the atom, the routing retains the initial value. This is similiar to Dynamic handler update in Clojure Ring/Compojure REPL but I'm having a hard time understanding what needs to be de/referenced where.
(ns mveroute
(:require
[org.httpkit.server :as srv]
[compojure.core :as cmpj]
[compojure.route :as route]
[clj-http.client :as client])
(:gen-class))
(def my-atom (atom "foobar"))
(def app
(cmpj/routes
(route/not-found {:status 400 :body #my-atom})))
(defn -main [& args]
(reset! my-atom "hello world")
(srv/run-server #'app {:port 8005})
;; "hello world" as expected
(println #my-atom)
;; still "foobar" but wanted "hello world"
(-> "http://localhost:8005"
(client/get {:throw-exceptions? false})
:body
println))
I thought warp-routes might have come to the rescue. But not how I've used it.
(defn atom-body [] {:status 200 :body #my-atom})
(cmpj/defroutes wrap-found
(route/not-found (atom-body)))
(def app
(cmpj/wrap-routes #'wrap-found {}))
The ultimate goal is a simple cli application that can set the resource/html root directory with command line arguments.
Try something like the following:
(defn not-found-fn
[req]
{:status 400 :body "not found again!"})
(def app
(cmpj/routes
(route/not-found not-found-fn)))
So inside of not-found-fn, you can construct the :body string any way you like. You could also have the string stored in an atom which is dereferenced by not-found-fn.
Side note:
Please see the following to clarify when you should use a Var object instead of just a symbol in your code:
When to use a Var instead of a function?

Clojure and Compojure: Response Map is nil

I'm using compojure for a basic web app, I have this code in core.clj:
(defroutes routes
(GET "/" [] (layout/application "Home" (contents/index)))
(route/resources "/"))
(def application (handler/site routes))
(defn -main []
(let [port (Integer/parseInt (or (System/getenv "PORT") "8090"))]
(jetty/run-jetty application {:port port :join? false})))
When I access the 0.0.0.0:8090 everything is loading ok, but I keep seeing this error:
java.lang.NullPointerException: Response map is nil
at ring.util.servlet$update_servlet_response.invokeStatic(servlet.clj:100)
at ring.util.servlet$update_servlet_response.invoke(servlet.clj:91)
at ring.util.servlet$update_servlet_response.invokeStatic(servlet.clj:95)
at ring.util.servlet$update_servlet_response.invoke(servlet.clj:91)
at ring.adapter.jetty$proxy_handler$fn__337.invoke(jetty.clj:27)
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:132)
at org.eclipse.jetty.server.Server.handle(Server.java:503)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:364)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168)
at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126)
at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765)
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683)
at java.base/java.lang.Thread.run(Thread.java:844)
Any idea what's going on?
#Svante is almost certainly correct. An easy way to verify is to use the spyx function from the Tupelo library:
(ns demo.core
(:use tupelo.core))
(defroutes routes
(GET "/" [] (spyx (layout/application "Home" (contents/index))))
(route/resources "/"))
which will print something like:
(layout/application "Home" (contents/index))) => nil
when run. spyx ("spy explicit") prints the expression you give it, an arrow, and the expression value. spy, spyx, spy-pretty, etc also return the value printed (unlike println which always returns nil) so you can insert a spy printout anywhere without disrupting the processing chain. Thus, you don't need to write something like:
(defroutes routes
(GET "/" [] (let [tmp-1 (layout/application "Home" (contents/index))]
(println "layout/application result => " tmp-1)
tmp-1)))
(route/resources "/"))
in order to get a debug message printed. In order to spy & friends, add this to the :dependencies in your project.clj:
[tupelo "0.9.138"]
Update
Hmmmm.... Not sure what could be the problem. I made a simple demo app from lein new compojure demo-compojure with the following:
(ns demo-compojure.handler
(:use tupelo.core)
(:require [compojure.core :refer :all]
[compojure.route :as route]
[ring.middleware.defaults :refer [wrap-defaults site-defaults]]))
(defn index []
(spy :index--result "Hello World"))
(defroutes app-routes
(GET "/" [] (spyx (index)))
(route/not-found "Not Found"))
(def app
(wrap-defaults app-routes site-defaults))
and results:
~/expr/demo-compojure > lein ring server
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Started server on port 3000
:index--result => "Hello World"
(index) => "Hello World"
So that is working. Also, int? is a basic Clojure function, so that is puzzling. Perhaps make a clean demo project like the above and take it from there?

How to apply ring-anti-forgery on specific reitit routes?

I keep getting "Invalid anti-forgery token" when wrapping specific routes created with metosin/reitit reitit.ring/ring-router. I've also tried reitit's middleware registry, but it didn't work too. Although I could just wrap the entire handler with wrap-session and wrap-anti-forgery, that defeats the reitit's advantage on allowing route-specific middleware.
(ns t.core
(:require [immutant.web :as web]
[reitit.ring :as ring]
[ring.middleware.anti-forgery :refer [wrap-anti-forgery]]
[ring.middleware.content-type :refer [wrap-content-type]]
[ring.middleware.params :refer [wrap-params]]
[ring.middleware.keyword-params :refer [wrap-keyword-params]]
[ring.middleware.session :refer [wrap-session]]
[ring.util.anti-forgery :refer [anti-forgery-field]]
[ring.util.response :as res]))
(defn render-index [_req]
(res/response (str "<form action='/sign-in' method='post'>"
(anti-forgery-field)
"<button>Sign In</button></form>")))
(defn sign-in [{:keys [params session]}]
(println "params: " params
"session:" session)
(res/redirect "/index.html"))
(defn wrap-af [handler]
(-> handler
wrap-anti-forgery
wrap-session
wrap-keyword-params
wrap-params))
(def app
(ring/ring-handler
(ring/router [["/index.html" {:get render-index
:middleware [[wrap-content-type]
[wrap-af]]}]
["/sign-in" {:post sign-in
:middleware [wrap-af]}]])))
(defn -main [& args]
(web/run app {:host "localhost" :port 7777}))
It turns out that metosin/reitit creates one session store for each route (refer to issue 205 for more information); in other words, ring-anti-forgery is not working because reitit does not use the same session store for each route.
As of the time of this answer, the maintainer suggests the following (copied from the issue for ease of reference within Stack Overflow):
mount the wrap-session outside of the router so there is only one instance of the mw for the whole app. There is :middleware option in ring-handler for this:
(require '[reitit.ring :as ring])
(require '[ring.middleware.session :as session])
(defn handler [{session :session}]
(let [counter (inc (:counter session 0))]
{:status 200
:body {:counter counter}
:session {:counter counter}}))
(def app
(ring/ring-handler
(ring/router
["/api"
["/ping" handler]
["/pong" handler]])
(ring/create-default-handler)
;; the middleware on ring-handler runs before routing
{:middleware [session/wrap-session]}))
create a single session store and use it within the routing table (all instances of the session middleware will share the single store).
(require '[ring.middleware.session.memory :as memory])
;; single instance
(def store (memory/memory-store))
;; inside, with shared store
(def app
(ring/ring-handler
(ring/router
["/api"
{:middleware [[session/wrap-session {:store store}]]}
["/ping" handler]
["/pong" handler]])))
Not shown in this answer is the third option that the maintainer calls for PR.

How do I mock a PUT request using ring.mock.request

How do I make this test pass:
(ns imp-rest.parser-test-rest
(:require [clojure.test :refer :all])
(:require [ring.mock.request :as mock] )
(:require [imp-rest.web :as w]))
(deftest test-parser-rest
(testing "put settings"
(w/app
(mock/request :put "/settings/coordinateName" "FOO" ))
(let [response (w/app (mock/request :get "/settings"))]
(println response )
(is (= (get (:body response) :coordinateName) "FOO")))))
it fails with:
FAIL in (test-parser-rest) (parser_test_rest.clj:30)
put settings
expected: (= (get (:body response) :coordinateName) "FOO")
actual: (not (= nil "FOO"))
Here's my handler:
(ns imp-rest.web
(:use compojure.core)
(:use ring.middleware.json-params)
(:require [clj-json.core :as json])
(:require [ring.util.response :as response])
(:require [compojure.route :as route])
(:require [imp-rest.settings :as s]))
(defn json-response [data & [status]]
{:status (or status 200)
:headers {"Content-Type" "application/json"}
:body (json/generate-string data)})
(defroutes handler
(GET "/settings" []
(json-response (s/get-settings)))
(GET "/settings/:id" [id]
(json-response (s/get-setting id)))
(PUT "/settings" [id value]
(json-response (s/put-setting id value)))
(route/not-found "Page not found") )
(def app
(-> handler
wrap-json-params))
which exposes this map (of settings):
(ns imp-rest.settings)
(def settings
(atom
{:coordinateName nil
:burnin nil
:nslices nil
:mrsd nil
}))
(defn get-settings []
#settings)
(defn get-setting [id]
(#settings (keyword id)))
(defn put-setting [id value]
(swap! settings assoc (keyword id) value)
value)
and the entry point:
(ns imp-rest.core
(:use ring.adapter.jetty)
(:require [imp-rest.web :as web]))
(defn -main
"Entry point"
[& args]
(do
(run-jetty #'web/app {:port 8080})
);END;do
);END: main
Now when I 'lein run' I can make a (working) request like this:
curl -X PUT -H "Content-Type: application/json" \
-d '{"id" : "coordinateName", "value" : "FOO"}' \
http://localhost:8080/settings
which is what I try to mock with the test. Any help appreciated.
If you want to have :id in your PUT /settings/:id route accepting body in format {"value": "..."}, you need to change your routes definition:
(defroutes handler
(GET "/settings" []
(json-response (s/get-settings)))
(GET "/settings/:id" [id]
(json-response (s/get-setting id)))
(PUT "/settings/:id" [id value]
(json-response (s/put-setting id value)))
(route/not-found "Page not found"))
And change how you call your PUT endpoint in the test:
(w/app
(-> (mock/request
:put
"/settings/coordinateName"
(json/generate-string {:value "FOO"}))
(mock/content-type "application/json")))
What was changed?
:id in your PUT URL route definition (/settings -> /settings/:id)
Your PUT request didn't send a correct request and content type.
If you want to have a PUT /settings route expecting {"id": "...", "value": "..."} request body, then you need to change how you create a mock request:
(w/app
(-> (mock/request
:put
"/settings"
(json/generate-string {:id "coordinateName" :value "FOO"}))
(mock/content-type "application/json"))
Your curl request specifies the parameters as JSON in the body of the PUT request, but your mock request tries to use URL parameters.
There are two options to resolve this:
compojure can automatically translate parameters, but only when the relevant middleware is present -- you have wrap-json-params added to your handler, but you're missing wrap-params. The answer from Piotrek Bzdyl amounts to making these params explicit in the compojure routes.
Alternatively, you can add the ID/value pair as JSON in the body of the mock request using request.mock.body.

How to set Content-Type header on Ring-Compojure application

I'm trying to get started with Clojure and Clojurescript by implementing a simple web app. Things are going pretty good so far and reading from different tutorials I've come up with the code below:
core.clj:
(ns myapp.core
(:require [compojure.core :as compojure]
[compojure.handler :as handler]
[compojure.route :as route]
[myapp.controller :as controller]))
(compojure/defroutes app-routes
(compojure/GET "/" [] controller/index)
(route/resources "/public")
(route/not-found "Not Found"))
(def app
(handler/site app-routes))
controller.clj:
(ns myapp.controller
(:use ring.util.response)
(:require [myapp.models :as model]
[myapp.templates :as template]))
(defn index
"Index page handler"
[req]
(->> (template/home-page (model/get-things)) response))
templates.clj:
(ns myapp.templates
(:use net.cgrand.enlive-html)
(:require [myapp.models :as model]))
(deftemplate home-page "index.html" [things]
[:li] (clone-for [thing things] (do->
(set-attr 'data-id (:id thing))
(content (:name thing)))))
The problem is I can't display non-ascii characters on the page and I don't know how to set HTTP headers on a page.
I see solutions like this but I simply can't figure out where place them in my code:
(defn app [request]
{:status 200
:headers {"Content-Type" "text/plain"}
:body "Hello World"})
P.S: Any suggestions about style and/or code organization are welcome.
Use ring.util.response:
(require '[ring.util.response :as r])
Then on your index function:
(defn index
"Index page handler"
[req]
(-> (r/response (->> (template/home-page (model/get-things)) response))
(r/header "Content-Type" "text/html; charset=utf-8")))
You can chain other actions on the response such as set-cookie and whatnot:
(defn index
"Index page handler"
[req]
(-> (r/response (->> (template/home-page (model/get-things)) response))
(r/header "Content-Type" "text/html; charset=utf-8")
(r/set-cookie "your-cookie-name"
"" {:max-age 1
:path "/"})))