[LIVY-81] Gateway timeout if client session takes long to start

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.2
• Fix Version/s: 0.2
• Component/s: Core
• Assignee: Marcelo Masiero Vanzin
• Reporter: Marcelo Masiero Vanzin
• Created: 24/Feb/16 18:54
• Updated: 02/May/16 18:12
• Resolved: 02/May/16 18:12

Description

If the session takes a while to start, the client receives a gateway timeout from the Livy server:

Caused by: java.io.IOException: Gateway Timeout: {"msg":"Gateway timeout"}
        at com.cloudera.livy.client.http.LivyConnection.sendRequest(LivyConnection.java:193)
        at com.cloudera.livy.client.http.LivyConnection.sendJSONRequest(LivyConnection.java:169)
        at com.cloudera.livy.client.http.LivyConnection.post(LivyConnection.java:145)
        at com.cloudera.livy.client.http.HttpClient.<init>(HttpClient.java:67)

It would be better, instead, if the start of a client session was monitored asynchronously, so that the code is less susceptible to these timeouts. If that's too much work, we need to at least figure out the source of this timeout, since it seems to come from the server and I didn't notice anything wrong in the server output.