Add support for multiple cors origins

plugin/config.json

@@ -3,5 +3,5 @@
     "apiLogPath": null,
     "webBindAddress": "127.0.0.1",
     "webBindPort": 8765,
-    "webCorsOrigin": "http://localhost"
+    "webCorsOrigin": ["http://localhost"]
 }

plugin/web.py

@@ -153,10 +153,20 @@ class WebServer:
             except ValueError:
                 body = json.dumps(None).encode('utf-8')
 
+        # handle multiple cors origins by checking the 'origin'-header against the allowed origin list from the config
+        webCorsOriginsSetting = util.setting('webCorsOrigin')
+        corsOrigin = "http://localhost"
+        if len(webCorsOriginsSetting) == 1:
+            corsOrigin = webCorsOriginsSetting[0]
+        elif b"origin" in req.headers:
+            originStr = req.headers[b"origin"].decode()
+            if originStr in webCorsOriginsSetting:
+                corsOrigin = originStr
+
         headers = [
             ['HTTP/1.1 200 OK', None],
             ['Content-Type', 'text/json'],
-            ['Access-Control-Allow-Origin', util.setting('webCorsOrigin')],
+            ['Access-Control-Allow-Origin', corsOrigin],
             ['Content-Length', str(len(body))]
         ]