Found the link where you can read about "deprecation" of the river concept, and the encouragement of writing individual bulk indexing code:
http://www.linkedin.com/groups/Official-guide-writing-ElasticSearch-rivers-3393294.S.268274223 Jörg -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAKdsXoGHk580yMezja9uXm-fj52huZAW1UVx9JcDYJJf1Z6BFw%40mail.gmail.com. For more options, visit https://groups.google.com/groups/opt_out.
