Elasticsearch strange behaviour for queries straight after insertion

Question

I am writing some integration tests for an app that uses Elasticsearch and I am experiencing a strange behaviour. If I insert a document and I query straight after that, I get different results every time. I suspect that, albeit the insertion itself will return, the indexing itself doesn't take place synchronously and, because of that, the query will experiment a race condition with unpredictable results.

If this is the case: is there a way to synchronize, so that when I run my queries, I know that they are ready and successful???

More details: I am using elasticsearch embedded and the query is a simple filter. The only odd thing is that I am using template files for the document model.

EDIT: I even tried to GET the document by ID after insertion, but the queries still return random results (unless I put a thread Sleep to wait some seconds).

Answer 1

From the Elasticsearch docs for the index API:

refresh

To refresh the index immediately after the operation occurs, so that the document appears in search results immediately, the refresh parameter can be set to true. Setting this option to true should ONLY be done after careful thought and verification that it does not lead to poor performance, both from an indexing and a search standpoint. Note, getting a document using the get API is completely realtime.

That's why my queries were returning weird results. Because indexing was sometimes not yet completed. Also, it is possible to do a refresh not as part of an insertion, using the _refresh endpoint:

$ curl -XPOST 'http://localhost:9200/twitter/_refresh'