rest.index/refresh fails for Elasticsearch 5

[hantuzun]

When I updated Elasticsearch to 5.5.2, our rest.index/refresh calls started to fail with a message from clj-http that "text/plain" content type is not acceptable.

Updating clojurewerkz.elastisch.rest's post function with a :content-type :json setting fixed the issue for me, without breaking other hundreds of tests using elastisch for our application:

(defn post
  ([^Connection conn ^String uri]
   (post conn uri {}))
  ([^Connection conn ^String uri {:keys [body] :as options}]
    (-> uri
        (http/post (merge (.http-opts conn)
                          options
                          {:accept :json
                           :content-type :json
                           ;:throw-exceptions false ;;ables to see ES when debugging
                           :body (json/encode body)}))
        (:body)
        (parse-safely))))

[michaelklishin]

See Supported ElasticSearch versions and #245.

[michaelklishin]

@hantuzun if you'd like to contribute this small improvement, a pull request against master would be appreciated.

[hantuzun]

Hi @michaelklishin, I fear that change might break some features in some of the many Elasticsearch versions supported.

[michaelklishin]

@hantuzun I don't see how adding a content type can break anything. In any case, no PRs for 5.x will be merged until 3.0 is released.

[hantuzun]

I've already forked elastisch to my account and we're using it. It'd be a hassle to fork it again for this PR that's not merged.

Hopefully 3.0 could be released soon and we could work on Elasticsearch 5.x support.