elasticmq-server-bin: add passthru.tests.elasticmqTest

simply starts an elasticmq server with a queue "foobar", attempts to put
a message to it from python then checks it arrives

pkgs/servers/elasticmq-server-bin/default.nix

@@ -1,6 +1,7 @@
-{ lib, stdenv, fetchurl, jdk, jre, makeWrapper }:
+{ lib, stdenv, fetchurl, jdk, jre, makeWrapper, runCommand, python3Packages, writeText }:
 
-stdenv.mkDerivation rec {
+let
+  elasticmq-server = stdenv.mkDerivation rec {
     pname = "elasticmq-server";
     version = "0.15.7";
 
@@ -31,4 +32,9 @@ stdenv.mkDerivation rec {
       platforms = platforms.unix;
       maintainers = with maintainers; [ peterromfeldhk ];
     };
-}
+  };
+in elasticmq-server.overrideAttrs (_: {
+  passthru.tests.elasticmqTest = import ./elasticmq-test.nix {
+    inherit elasticmq-server runCommand python3Packages writeText;
+  };
+})

pkgs/servers/elasticmq-server-bin/elasticmq-test.nix

@@ -0,0 +1,47 @@
+{ elasticmq-server, python3Packages, runCommand, writeText}:
+
+runCommand "${elasticmq-server.name}-tests" (let
+  commonPy = ''
+    import boto3
+    client = boto3.resource(
+      "sqs",
+      endpoint_url="http://localhost:9324",
+      region_name="elasticmq",
+      aws_secret_access_key="x",
+      aws_access_key_id="x",
+      use_ssl=False,
+    )
+    queue = client.get_queue_by_name(QueueName="foobar")
+  '';
+in {
+  buildInputs = with python3Packages; [ python boto3 ];
+  emqConfig = writeText "emq-test.conf" ''
+    generate-node-address = true
+
+    queues {
+      foobar {}
+    }
+  '';
+  putMessagePy = writeText "put_message.py" ''
+    ${commonPy}
+    queue.send_message(MessageBody="bazqux")
+  '';
+  checkMessagePy = writeText "check_message.py" ''
+    ${commonPy}
+    messages = queue.receive_messages()
+    print(f"Received {messages!r}")
+    assert len(messages) == 1
+    assert messages[0].body == "bazqux"
+  '';
+}) ''
+  JAVA_TOOL_OPTIONS="-Dconfig.file=$emqConfig" ${elasticmq-server}/bin/elasticmq-server &
+  SERVER_PID=$!
+  sleep 10
+
+  python $putMessagePy
+  python $checkMessagePy
+  touch $out
+
+  # needed on darwin
+  kill $SERVER_PID
+''