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elasticsearchquerydsl

In Elasticsearch searches, are query string parameters for GET requests and the "Query DSL" for POST requests functionally equivalent?

I'm trying to create a small app that displays some simple visualizations from data indexed on Elasticsearch (on an AWS managed Elasticsearch service).

Since, to the best of my knowledge, the degree of access control that AWS offers over its ES service is based on allowing specific HTTP verbs (GET, POST, etc), to simplify my life and the ES admin's, I'm granting this app "read only" permissions, so only GET and HEAD.

However, I see that for its search API, ES exposes a GET endpoint that works with query string parameters, and a POST endpoint that works with a JSON based "Query DSL". This DSL seems to be the preferred method in all examples I have seen online and in the books.

Given the predominance of the Query DSL throughout the documentation, I was wondering:

  1. Does the the Query DSL exposes functionality that standard query string parameters don't, or are they both functionally equivalent?
  2. Does the POST search endpoint result in any data being actually POSTED, or is this only a workaround to allow to send JSON as a query that breaks a little bit with REST conventions?
Solution

    1. As per the docs

      You can use query parameters to define your search criteria directly in the request URI, rather than in the request body. Request URI searches do not support the full Elasticsearch Query DSL, but are handy for testing.

    2. The GET behavior is slightly confusing but even Kibana sends a POST in the background when you perform a GET with a body. If you have to use GET, some query results might be unexpected. What's your exact use case? Which queries are we talking?

    FYI more useful info is here and here.