NPE on car/with-new-pubsub-listener

[sritchie]

Hey,

Little bug in my upgrade from 2.3.1. When I try to run the following code with an empty spec map (ie, local redis), all's well:

(car/with-new-pubsub-listener (:spec conf)
              {"results" (fn [[message-type topic-name msg]]
                           (broadcast! msg))}
              (car/subscribe "results"))

However, when conf is {:uri "redistogo-url"}, this exception shows up:

java.lang.NullPointerException
    at clojure.core$deref_future.invoke(core.clj:2108)
    at clojure.core$deref.invoke(core.clj:2129)
    at taoensso.carmine.protocol$get_parsed_replies.invoke(protocol.clj:203)
    at taoensso.carmine.connections$make_new_connection$fn__25792.invoke(connections.clj:55)
    at taoensso.carmine.connections$make_new_connection.invoke(connections.clj:56)
    at paddleguru.websocket.PubSub.start_BANG_(form-init1409143132977261857.clj:5)
    at paddleguru.lifecycle$start_system$fn__10186.invoke(lifecycle.clj:15)
    at clojure.lang.ArrayChunk.reduce(ArrayChunk.java:63)

any ideas?

[ptaoussanis]

Hey Sam, thanks a lot for reporting this. Refactored some low-level connection stuff in 2.4 which is almost certainly the culprit. Will try take a look w/in the next 2 hours and get back to you.

Cheers! :-)

[ptaoussanis]

Okay, dug into this. Turns out the 2.4 refactor was uncovering a subtle Pub/Sub connection bug that's been around since before v1.

Just pushed v2.4.3 - I believe that should sort out the problem but please confirm when you can?

Cheers!

[sritchie]

Looks like it works. Thanks for the patch!

[ptaoussanis]

Okay, great - thanks for following up.