NullPointerException streaming es to es

FWIW, I'm streaming from a self-hosted ES cluster (0.90) to one hosted by Amazon Elasticsearch Service (1.5). I'm not sure that's relevant however, since the stream doesn't even start.

OS: Ubuntu 12.04

$ java -version
openjdk version "1.8.0_111"
OpenJDK Runtime Environment (build 1.8.0_111-8u111-b14-3~12.04-b14)
OpenJDK 64-Bit Server VM (build 25.111-b14, mixed mode)
$ ./stream2es es --source http://x.x.x.x:9200/indexname --target https://my-tesing-cluster.us-east-1.es.amazonaws.com/indexname
java.lang.NullPointerException
        at clojure.core$val.invokeStatic(core.clj:1530)
        at clojure.core$val.invoke(core.clj:1525)
        at stream2es.es$fn__6449.invokeStatic(es.clj:163)
        at stream2es.es$fn__6449.invoke(es.clj:130)
        at stream2es.es$fn__6312$G__6303__6319.invoke(es.clj:17)
        at stream2es.es$fn__6451.invokeStatic(es.clj:166)
        at stream2es.es$fn__6451.invoke(es.clj:130)
        at stream2es.es$fn__6371$G__6305__6376.invoke(es.clj:17)
        at stream2es.stream.es$fn__6682.invokeStatic(es.clj:59)
        at stream2es.stream.es$fn__6682.invoke(es.clj:26)
        at stream2es.stream$fn__6565$G__6547__6572.invoke(stream.clj:16)
        at stream2es.main$ensure_index.invokeStatic(main.clj:309)
        at stream2es.main$ensure_index.invoke(main.clj:303)
        at stream2es.main$main.invokeStatic(main.clj:321)
        at stream2es.main$main.invoke(main.clj:317)
        at stream2es.main$_main.invokeStatic(main.clj:339)
        at stream2es.main$_main.doInvoke(main.clj:337)
        at clojure.lang.RestFn.applyTo(RestFn.java:137)
        at stream2es.main.main(Unknown Source)
2017-01-05T23:41:17.546+0000 ERROR unexpected exception: see above
2017-01-05T23:41:17.742+0000 INFO  00:00.333 0.0d/s 0.0K/s (0.0mb) indexed 0 streamed 0 errors 0

elastic / stream2es

NullPointerException streaming es to es #68