I just learned that Flink savepoints API was refactored to require using HTTP POST.
That's fine otherwise, but makes life harder when Flink is run on top of YARN. I've added example calls below to show how POST is declined by the hadoop-yarn-server-web-proxy*, which only supports GET and PUT. Can you think of any solution to this? If I would be able to determine the actual host & port for Flink UI, I could use that instead of the proxy address. But that would probably require opening at least one more port, so it's not the optimal solution either. Ideally I would have Flink REST API completely accessible with GET and PUT methods. To me it seems like AWS EMR will also hit this issue as soon as they start supporting Flink 1.5, because they seem to run Flink as a YARN app. *) https://github.com/apache/hadoop/blob/trunk/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-web-proxy/src/main/java/org/apache/hadoop/yarn/server/webproxy/WebAppProxyServlet.java#L296-L306 $ http POST http://10.0.10.71:20888/proxy/application_1522844153347_0001/jobs/652e207f8578574d4a322e23d4f8b908/checkpoints HTTP/1.1 405 HTTP method POST is not supported by this URL Cache-Control: must-revalidate,no-cache,no-store Content-Length: 1523 Content-Type: text/html; charset=iso-8859-1 Date: Wed, 04 Apr 2018 12:48:05 GMT Date: Wed, 04 Apr 2018 12:48:05 GMT Pragma: no-cache Pragma: no-cache <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"/> <title>Error 405 HTTP method POST is not supported by this URL</title> </head> <body><h2>HTTP ERROR 405</h2> <p>Problem accessing /proxy/application_1522844153347_0001/jobs/652e207f8578574d4a322e23d4f8b908/checkpoints. Reason: <pre> HTTP method POST is not supported by this URL</pre></p><hr /><i><small>Powered by Jetty://</small></i><br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> <br/> </body> </html> $ http PUT http://10.0.10.71:20888/proxy/application_1522844153347_0001/jobs/652e207f8578574d4a322e23d4f8b908/checkpoints HTTP/1.1 404 Not Found Access-Control-Allow-Origin: * Cache-Control: no-cache Content-Length: 25 Content-Type: application/json; charset=UTF-8 Date: Wed, 04 Apr 2018 12:48:09 GMT Date: Wed, 04 Apr 2018 12:48:09 GMT Expires: Wed, 04 Apr 2018 12:48:09 GMT Expires: Wed, 04 Apr 2018 12:48:09 GMT Pragma: no-cache Pragma: no-cache { "errors": [ "Not found." ] } ^ expected to get this from flink because there's no PUT /checkpoints.
