├── example ├── server │ ├── .gitignore │ ├── resources │ │ └── public │ │ │ ├── out │ │ │ ├── index.html │ │ │ └── eventual-client-example.js │ ├── src │ │ └── eventual │ │ │ ├── server.clj │ │ │ └── servlet.clj │ └── project.clj └── client │ ├── .gitignore │ ├── index.html │ ├── src │ └── eventual │ │ └── client.cljs │ └── project.clj ├── .gitignore ├── project.clj ├── test └── ninjudd │ └── eventual │ └── server_test.clj ├── src └── ninjudd │ └── eventual │ ├── client.cljs │ └── server.clj ├── README.md └── LICENSE /example/server/.gitignore: -------------------------------------------------------------------------------- 1 | target/ -------------------------------------------------------------------------------- /example/server/resources/public/out: -------------------------------------------------------------------------------- 1 | ../../../client/out -------------------------------------------------------------------------------- /example/client/.gitignore: -------------------------------------------------------------------------------- 1 | eventual-client-example.js 2 | out/ -------------------------------------------------------------------------------- /example/server/resources/public/index.html: -------------------------------------------------------------------------------- 1 | ../../../client/index.html -------------------------------------------------------------------------------- /example/server/resources/public/eventual-client-example.js: -------------------------------------------------------------------------------- 1 | ../../../client/eventual-client-example.js -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | /target 2 | /classes 3 | /checkouts 4 | pom.xml 5 | pom.xml.asc 6 | *.jar 7 | *.class 8 | /.lein-* 9 | /.nrepl-port 10 | -------------------------------------------------------------------------------- /example/server/src/eventual/server.clj: -------------------------------------------------------------------------------- 1 | (ns eventual.server 2 | (:gen-class)) 3 | 4 | (defn -main [& args] 5 | (require 'eventual.servlet) 6 | ((ns-resolve 'eventual.servlet 'start))) 7 | -------------------------------------------------------------------------------- /example/client/index.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 |

server-sent events test

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9 | 10 | 11 | 12 | 13 | 14 | -------------------------------------------------------------------------------- /project.clj: -------------------------------------------------------------------------------- 1 | (defproject com.ninjudd/eventual "0.5.5" 2 | :description "Server-Sent Event and EventSource helpers for core.async." 3 | :url "http://github.com/ninjudd/eventual" 4 | :license {:name "Eclipse Public License" 5 | :url "http://www.eclipse.org/legal/epl-v10.html"} 6 | :dependencies [[org.clojure/clojure "1.5.1"] 7 | [org.clojure/core.async "0.1.267.0-0d7780-alpha"]] 8 | :profiles {:dev {:dependencies [[cheshire "5.2.0"]]}}) 9 | -------------------------------------------------------------------------------- /example/server/project.clj: -------------------------------------------------------------------------------- 1 | (defproject eventual-server-example "0.1.0" 2 | :description "Example Server-Sent Events server using eventual." 3 | :dependencies [[org.clojure/clojure "1.5.1"] 4 | [com.ninjudd/ring "1.2.2"] 5 | [com.ninjudd/ring-async "0.2.3"] 6 | [com.ninjudd/eventual "0.1.1"] 7 | [org.clojure/core.async "0.1.267.0-0d7780-alpha"] 8 | [compojure "1.1.5"] 9 | [cheshire "5.2.0"]] 10 | :main eventual.server) 11 | -------------------------------------------------------------------------------- /example/client/src/eventual/client.cljs: -------------------------------------------------------------------------------- 1 | (ns eventual.client 2 | (:require [cljs.core.async :refer [! ! events event)) 19 | (! ! events {:foo i})) 16 | (close! events)) 17 | (is (= ["data: {:foo 0}" 18 | "data: {:foo 1}" 19 | "data: {:foo 2}" 20 | "data: {:foo 3}" 21 | "data: {:foo 4}"] 22 | (slurp-events (edn-events events)))))) 23 | 24 | (deftest test-json-events 25 | (let [events (chan)] 26 | (go (dotimes [i 5] 27 | (>! events {:foo i})) 28 | (close! events)) 29 | (is (= ["data: {\"foo\":0}" 30 | "data: {\"foo\":1}" 31 | "data: {\"foo\":2}" 32 | "data: {\"foo\":3}" 33 | "data: {\"foo\":4}"] 34 | (slurp-events (json-events events)))))) 35 | -------------------------------------------------------------------------------- /src/ninjudd/eventual/client.cljs: -------------------------------------------------------------------------------- 1 | (ns ninjudd.eventual.client 2 | (:require [cljs.core.async :as async] 3 | [cljs.reader :refer [read-string]])) 4 | 5 | (defn make-event [f event] 6 | (-> (f (.-data event)) 7 | (vary-meta merge {:event-id (.-lastEventId event) 8 | :event-type (keyword (.-type event))}))) 9 | 10 | (defn event-source [f url & [event-types channel]] 11 | (let [event-types (or event-types [:message]) 12 | source (new js/EventSource url) 13 | channel (or channel (async/chan))] 14 | (doseq [event-type event-types] 15 | (.addEventListener source (name event-type) 16 | (fn [event] 17 | (async/put! channel (make-event f event))))) 18 | (set! (.-onerror source) 19 | (fn [error] 20 | (.close source) 21 | (async/close! channel))) 22 | {:event-source source 23 | :channel channel})) 24 | 25 | (defn edn-event-source [url & [event-types channel]] 26 | (event-source read-string url event-types channel)) 27 | 28 | (defn json-event-source [url & [event-types channel]] 29 | (event-source #(.parse js/JSON %) url event-types channel)) 30 | 31 | (defn close-event-source! [{:keys [channel event-source]}] 32 | (when event-source 33 | (.close event-source)) 34 | (async/close! channel)) 35 | -------------------------------------------------------------------------------- /src/ninjudd/eventual/server.clj: -------------------------------------------------------------------------------- 1 | (ns ninjudd.eventual.server 2 | (:require [clojure.core.async :refer [go ! close! chan alts! timeout]] 3 | [cheshire.core :as json])) 4 | 5 | (defn add-sse-headers [request] 6 | (update-in request [:headers] assoc 7 | "Content-Type" "text/event-stream; charset=utf-8" 8 | "Cache-Control" "no-cache")) 9 | 10 | (defn data [& args] 11 | (.getBytes (apply str args) "UTF-8")) 12 | 13 | (defn sse-channel [f events & [opts]] 14 | (let [out (chan) 15 | aggregate (:aggregate-event-id opts) 16 | disconnect (if-let [t (:timeout opts)] 17 | (timeout t) 18 | (chan))] 19 | (go (when-let [retry (:client-retry opts)] 20 | (>! out (data "retry: " retry "\n"))) 21 | (loop [last-event-id nil] 22 | (when-not @(.closed out) 23 | (let [keepalive (timeout (:keepalive opts 25000)) 24 | [event ch] (alts! [events keepalive disconnect])] 25 | (cond 26 | (= ch events) 27 | (when event 28 | (let [event-id (:event-id (meta event)) 29 | event-id (if (and aggregate event-id last-event-id) 30 | (aggregate event-id last-event-id) 31 | event-id)] 32 | (when event-id 33 | (>! out (data "id: " event-id "\n"))) 34 | (when-let [event-type (:event-type (meta event))] 35 | (>! out (data "event: " (name event-type) "\n"))) 36 | (>! out (data "data: " (f event) "\n\n")) 37 | (>! out :flush) 38 | (recur (or event-id last-event-id)))) 39 | (= ch keepalive) 40 | (do (>! out (data ":keepalive\n")) 41 | (>! out :flush) 42 | (recur last-event-id)))))) 43 | (close! events) 44 | (close! out)) 45 | out)) 46 | 47 | (defn edn-events [events & [opts]] 48 | (add-sse-headers 49 | {:body (sse-channel pr-str events opts)})) 50 | 51 | (defn json-events [events & [opts]] 52 | (add-sse-headers 53 | {:body (sse-channel json/generate-string events opts)})) 54 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # eventual 2 | 3 | Server-Sent Event and EventSource helpers for core.async. 4 | 5 | ## Installation 6 | 7 | To use eventual, add the following to your `:dependencies`: 8 | 9 | [com.ninjudd/eventual "0.5.0"] 10 | 11 | ## Server 12 | 13 | To create a handler that returns a stream of Server-Sent Events, you need use 14 | [ring-async](http://github.com/ninjudd/ring-async) or some other servlet adapter that supports 15 | asynchronous responses by returning a core.async channel for body. 16 | 17 | ```clj 18 | (ns server-events-sample 19 | (:require [clojure.core.async :refer [go >! chan close!]] 20 | [ninjudd.eventual.server :refer [edn-events]] 21 | [ring.adapter.jetty-async :refer [run-jetty-async]])) 22 | 23 | (defn sse-handler [request] 24 | (let [events (chan)] 25 | (go (loop [...] 26 | (if ... 27 | (>! events event) 28 | (recur ...))) 29 | (close! events)) 30 | (edn-events events))) 31 | 32 | (defn start [] 33 | (run-jetty-async sse-handler {:join? false :port 8000})) 34 | ``` 35 | 36 | ## Client 37 | 38 | To connect to a server endpoint that returns an event stream in ClojureScript, eventual provides a 39 | helper function that returns a core.async channel but user `EventSource` behind the scenes. 40 | 41 | ```clj 42 | (ns client-events-sample 43 | (:require [cljs.core.async :refer [! events (with-meta event {:event-type :add, :event-id 1234}))) 63 | ``` 64 | 65 | To receive events besides `message` on the client, you have to provide a list of events you 66 | handle. Events taken from the channel will have metadata with their type and id. 67 | 68 | ```clj 69 | (edn-events "http://.../events" [:add :remove]) 70 | ``` 71 | 72 | ## License 73 | 74 | Copyright © 2015 Justin Balthrop 75 | 76 | Distributed under the Eclipse Public License either version 1.0 or (at 77 | your option) any later version. 78 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | THE ACCOMPANYING PROGRAM IS PROVIDED UNDER THE TERMS OF THIS ECLIPSE PUBLIC 2 | LICENSE ("AGREEMENT"). ANY USE, REPRODUCTION OR DISTRIBUTION OF THE PROGRAM 3 | CONSTITUTES RECIPIENT'S ACCEPTANCE OF THIS AGREEMENT. 4 | 5 | 1. 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