[#9] Support ring.core.protocols/StreamableResponseBody

deps.edn

@@ -17,7 +17,8 @@
          :extra-deps {org.clojure/test.check {:mvn/version "1.1.1"}
                       less-awful-ssl/less-awful-ssl {:mvn/version "1.0.6"}
                       eftest/eftest {:mvn/version "0.6.0"}
-                      clj-http/clj-http {:mvn/version "3.12.0"}}}
+                      clj-http/clj-http {:mvn/version "3.12.0"}
+                      ring/ring-core {:mvn/version "1.10.0"}}}
   :project
   {:extra-deps {io.github.exoscale/tools.project {:git/sha "4ad527fac7bdc24f649404205ca31754339f856d"}}
    :ns-default exoscale.tools.project

src/s_exp/mina/response.clj

@@ -7,6 +7,12 @@
            (io.helidon.webserver.http ServerResponse)
            (java.io FileInputStream InputStream OutputStream)))
 
+(def ^:no-doc ring-core-loaded
+  (try
+    (require 'ring.core.protocols)
+    true
+    (catch Throwable _ false)))
+
 (defprotocol BodyWriter
   (write-body! [x server-response]))
 
@@ -37,6 +43,16 @@
   (write-body! [o server-response]
     (.send ^ServerResponse server-response o)))
 
+(when ring-core-loaded
+  (extend-protocol BodyWriter
+    Object
+    (write-body! [o server-response]
+      (let [StreamableResponseBody @(ns-resolve 'ring.core.protocols 'StreamableResponseBody)
+            write-body-to-stream (ns-resolve 'ring.core.protocols 'write-body-to-stream)]
+        (if (satisfies? StreamableResponseBody o)
+          (write-body-to-stream o nil (.outputStream server-response))
+          (.send ^ServerResponse server-response o))))))
+
 (defn header-name ^HeaderName [ring-header-name]
   (HeaderNames/createFromLowercase (name ring-header-name)))
 
@@ -62,4 +78,3 @@
   (set-headers! server-response headers)
   (set-status! server-response status)
   (write-body! body server-response))
-

test/s_exp/mina_test.clj

@@ -3,7 +3,9 @@
             [clojure.string :as str]
             [clojure.test :refer :all]
             [less.awful.ssl :as ls]
-            [s-exp.mina :as m])
+            [s-exp.mina :as m]
+            [ring.core.protocols :as p]
+            [clojure.java.io :as io])
   (:import (io.helidon.common.tls Tls TlsClientAuth)
            (io.helidon.common.tls TlsConfig)))
 
@@ -94,5 +96,19 @@
                                    :trust-store "test/keystore.jks"
                                    :trust-store-pass "password"}))))))
 
-
-
+(deftest test-streamable-body
+  (with-server {:handler (fn [_req]
+                           {:status 200
+                            :headers {"content-type" "text/event-stream"
+                                      "transfer-encoding" "chunked"}
+                            :body (reify p/StreamableResponseBody
+                                    (write-body-to-stream [_ _ output-stream]
+                                      (with-open [w (io/writer output-stream)]
+                                        (doseq [n (range 1 6)]
+                                          (doto w
+                                            (.write (str "data: " n "\n\n"))
+                                            (.flush))))))})}
+    (let [resp (client/get *endpoint*)]
+      (is (status-ok? resp))
+      (is (= "data: 1\n\ndata: 2\n\ndata: 3\n\ndata: 4\n\ndata: 5\n\n"
+             (:body resp))))))