Hiccup template function - clojure

I'm trying to add the following Hiccup template function to my file
(defn d3-page [title js body & {:keys [extra-js] :or {extra-js []}}]
(html5
[:head
[:title title]
(include-css "/css/nv.d3.css"))
(include-css "/css/style.css")]
[:body
(concat
[body]
[(include-js "http://d3js.org/d3.v3.min.js")
(include-js (str "https://raw.github.com"
"/novus/nvd3"
"/master/nv.d3.min.js")]
(map include-js extra-js)
[(include-js "/js/script.js")
(javascript-tag js)])]))
but keep getting an unmatched delimiter when I run lein ring server. This comes from Clojure Data Cookbook, so I am surprised to find an error and suspect the error is just on my end. Below is the rest of the code in the file:
(ns web-viz.web
(:require [compojure.route :as route]
[compojure.handler :as handler]
[clojure.string :as str])
(:use compojure.core
ring.adapter.jetty
[ring.middleware.content-type :only
(wrap-content-type)]
[ring.middleware.file :only (wrap-file)]
[ring.middleware.file-info :only
(wrap-file-info)]
[ring.middleware.stacktrace :only
(wrap-stacktrace)]
[ring.util.response :only (redirect)]
[hiccup core element page]
[hiccup.middleware :only (wrap-base-url)]))
(defn d3-page...as above
...)
(deftype Group [key values])
(deftype Point [x y size])
(defn add-label [chart axis label]
(if-not (nil? label)
(.axisLabel (aget chart axis) label)))
(defn add-axes-labels [chart x-label y-label]
(doto chart (add-label "xAxis" x-label)
(add-label "yAxis" y-label)))
(defn populate-node [selector chart groups transition continuation]
(-> (.select js/d3 selector)
(.datum groups)
(.transition)
(.duration (if transition 500 0))
(.call chart)
(.call continuation)))
(defn force-layout-plot []
(d3-page "Force-Directed Layout"
"webviz.force.force_layout();"
[:div#force.chart [:svg]]))
(defroutes site-routes
(GET "/force" [] (force-layout-plot))
(GET "/force/data.json" []
(redirect "/data/census-race.json"))
(route/resources "/")
(route/not-found "Page not found"))
(def app (-> (handler/site site-routes)))

In line 5
(include-css "/css/nv.d3.css"))
There's an extra ) there.
And in line 13,
"/master/nv.d3.min.js")]
There's one ) missing. Should be
"/master/nv.d3.min.js"))]
You should use an editor which can do the matching of braces, parentheses, and brackets, etc. automatically.

Related

No view is being rendered in re-frame app

Here's a simple re-frame app that I tried to create based on the existing example project in re-frame's github repo. But it is only displaying things from the html file. Seems like no event is being dispatched. Can anyone point out what am I doing wrong? Thanks.
(ns simple.core
(:require [reagent.core :as reagent]
[re-frame.core :as rf]
[clojure.string :as str]))
(rf/reg-event-db
:rand
(fn [db [_ _]]
(assoc db :winner ( + 2 (rand-int 3)))))
(rf/reg-sub
:winner
(fn [db _]
(:winner db)))
(def participants ["Alice" "Bob" "Ellie"])
(defn winners-name
[idx]
(get participants idx))
(defn show-winner
[]
[:h1
(winners-name
(#(rf/subscribe [:winner])))])
(defn ui
[]
[:div
[:h1 "Lottery"]
[show-winner]])
(defn ^:export run
[]
(rf/dispatch-sync [:rand])
(reagent/render [ui]
(js/document.getElementById "app")))
The :rand handler will produce nil most times since you are adding 2 to the generated value and the participants vector only has 3 entries.
The issue is caused because of a pair of extra parenthesis around the deref thing. So the function winners-name is treating it as a list instead of an integer.
(winners-name
(#(rf/subscribe [:winner]))

Get Clojure map from POST request

Here is my code:
(ns cowl.server
(:use compojure.core)
(:require [ring.adapter.jetty :as jetty]
[ring.middleware.params :as params]
[ring.middleware.json :refer [wrap-json-response]]
[ring.util.response :refer [response]]
[clojure.data.json :as json]
[cowl.db :as db]))
(defroutes main-routes
(POST "/api/news/as-read" { body :body }
(str (json/read-str (slurp body))))))
(def app
(-> main-routes
wrap-json-response))
(defn serve []
(jetty/run-jetty app {:port 3000}))
If I post this JSON: { "name": "demas" } I get {"name" "demas"}. But this is not a Clojure map.
I need something like (:name (json/read-str (slurp body))). How can I get it ?
Instead of handling body JSON parsing by yourself, you can use ring.middleware.json/wrap-json-body. Just modify your middleware setup:
(def app
(-> main-routes
wrap-json-response
(wrap-json-body {:keywords? true})))
and your request :body will become JSON parsed to Clojure data.
You may wish to use the keywordize-keys function:
http://clojuredocs.org/clojure.walk/keywordize-keys
(ns xyz.core
(:require [clojure.walk :as walk]))
(walk/keywordize-keys {"a" 1 "b" 2})
;;=> {:a 1 :b 2}
You will probably also find that the Cheshire lib is the best way to process JSON in Clojure: https://github.com/dakrone/cheshire#decoding
;; parse some json
(parse-string "{\"foo\":\"bar\"}")
;; => {"foo" "bar"}
;; parse some json and get keywords back
(parse-string "{\"foo\":\"bar\"}" true) ; true -> want keyword keys
;; => {:foo "bar"}
;; parse some json and munge keywords with a custom function
(parse-string "{\"foo\":\"bar\"}" (fn [k] (keyword (.toUpperCase k))))
;; => {:FOO "bar"}
You can use :key-fn function as well:
(json/read-str (return :body)
:key-fn keyword)
Doing this you will parse your JSON to default map syntax.

How to convert HTML tag with style to Hiccup? React problems

I'm trying to parse HTML with CSS into Hiccup in a Reagent project. I am using Hickory. When I parse HTML with inline CSS, React throws an exception.
(map
as-hiccup (parse-fragment "<div style='color:red'>test</div>")
)
The above generates [:div {:style color:red} "test"] & Reactjs returns exception from Reactjs:
Violation: The style prop expects a mapping from style properties to values, not a string.
I believe [:div {:style {"color" "red"}} "test"] must be returned instead.
Here is the code view:
(ns main.views.job
(:require [reagent.core :as reagent :refer [atom]]
[hickory.core :refer [as-hiccup parse parse-fragment]]))
(enable-console-print!)
(defn some-view [uid]
[:div
(map as-hiccup (parse-fragment "<div style='color:red'>test</div>"))
])
The whole repo is here and it works. I added the parsing from style tag to a map for React in the core.cljs file:
(ns hickory-stack.core
(:require [clojure.string :as s]
[clojure.walk :as w]
[reagent.core :as reagent :refer [atom]]
[hickory.core :as h]))
(enable-console-print!)
(defn string->tokens
"Takes a string with syles and parses it into properties and value tokens"
[style]
{:pre [(string? style)]
:post [(even? (count %))]}
(->> (s/split style #";")
(mapcat #(s/split % #":"))
(map s/trim)))
(defn tokens->map
"Takes a seq of tokens with the properties (even) and their values (odd)
and returns a map of {properties values}"
[tokens]
{:pre [(even? (count tokens))]
:post [(map? %)]}
(zipmap (keep-indexed #(if (even? %1) %2) tokens)
(keep-indexed #(if (odd? %1) %2) tokens)))
(defn style->map
"Takes an inline style attribute stirng and converts it to a React Style map"
[style]
(tokens->map (string->tokens style)))
(defn hiccup->sablono
"Transforms a style inline attribute into a style map for React"
[coll]
(w/postwalk
(fn [x]
(if (map? x)
(update-in x [:style] style->map)
x))
coll))
;; Test Data
(def good-style "color:red;background:black; font-style: normal ;font-size : 20px")
(def html-fragment
(str "<div style='" good-style "'><div id='a' class='btn' style='font-size:30px;color:white'>test1</div>test2</div>"))
;; Rendering
(defn some-view []
[:div (hiccup->sablono
(first (map h/as-hiccup (h/parse-fragment html-fragment))))])
(reagent/render-component [some-view]
(. js/document (getElementById "app")))

Is there some way to let compojure support type conversion automatically?

Now can use compojure this way:
(GET ["/uri"] [para1 para2]
)
Para1 and para2 are all of type String.
I would like to let it know the type correcttly,like this:
(GET ["/uri"] [^String para1 ^Integer para2]
)
It can convert para1 to be Sting and para2 to Integer.
Is there some library or good way to do this?
This is possible as of Compojure 1.4.0 using the syntax [x :<< as-int]
This is not currently possible with only Compojure.
You could use Prismatic schema coercion.
(require '[schema.core :as s])
(require '[schema.coerce :as c])
(require '[compojure.core :refer :all])
(require '[ring.middleware.params :as rparams])
(def data {:para1 s/Str :para2 s/Int s/Any s/Any})
(def data-coercer (c/coercer data c/string-coercion-matcher ))
(def get-uri
(GET "/uri" r
(let [{:keys [para1 para2]} (data-coercer (:params r))]
(pr-str {:k1 para1 :k2 (inc para2)}))))
(def get-uri-wrapped
(let [keywordizer (fn [h]
(fn [r]
(h (update-in r [:params] #(clojure.walk/keywordize-keys %)))))]
(-> get-uri keywordizer rparams/wrap-params)))
Here is a sample run:
(get-uri-wrapped {:uri "/uri" :query-string "para1=a&para2=3" :request-method :get})
{:status 200,
:headers {"Content-Type" "text/html; charset=utf-8"},
:body "{:k1 \"a\", :k2 4}"}

Can't require goog.fx.Dragger in ClojureScript

I'm trying to build a small om-component that uses goog.fx.Dragger to make a target draggable. I require goog.fx.Dragger :as dragger and like so:
(ns om-draggable-me.core
(:require [om.core :as om :include-macros true]
[om.dom :as dom :include-macros true]
[goog.fx.Dragger :as dragger]))
When i use it like:
(defn draggable [app owner]
(reify
om/IDidMount
(did-mount [_]
(let [target (om/get-node owner)]
(dragger. target)))
om/IRender
(render [_]
(dom/div #js {:id "drag-box" :className "drag-box"}))))
I get the compiler warning:
WARNING: Use of undeclared Var om-draggable-me.core/dragger at line 22 src/cljs/om_draggable_me/core.cljs
Seen other examples of the use of goog.fx.DragDrop so why does not this work?
In your require form, dragger is a namespace alias
[goog.fx.Dragger :as dragger]
which is intended to be used like this:
dragger/your-var
;; the same as goog.fx.Dragger/your-var
while in your script, it was used as if it's a var:
(dragger. target)
and, as the compiler complained, such var hasn't been defined.
You can see people refer to clojure.string like this:
(require '[clojure.string :as str])
without worrying about conflicting with clojure.core/str function:
(str/join ", " [1 2 3])
(str "hello" "world")
For some reason the alias did not work, it works with fully qualified name:
(did-mount [_]
(let [target (om/get-node owner)]
(goog.fx.Dragger. target)))