ElasticSearch 5.0 not compatible of current OGR ES driver

[Even Rouault]

A number of REST API changes:

• creating a mapping requires a PUT ( ​https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-create-index.html ) whereas it required before a POST ( ​https://www.elastic.co/guide/en/elasticsearch/reference/2.4/indices-create-index.html )

Quick fix/workaround

Index: ogr/ogrsf_frmts/elastic/ogrelasticdatasource.cpp
===================================================================
--- ogr/ogrsf_frmts/elastic/ogrelasticdatasource.cpp	(révision 36400)
+++ ogr/ogrsf_frmts/elastic/ogrelasticdatasource.cpp	(copie de travail)
@@ -495,6 +495,7 @@
     bool bRet = true;
     char** papszOptions = NULL;
     papszOptions = CSLAddNameValue(papszOptions, "POSTFIELDS", data.c_str());
+    papszOptions = CSLAddNameValue(papszOptions, "CUSTOMREQUEST", "PUT");
     papszOptions = CSLAddNameValue(papszOptions, "HEADERS",
             "Content-Type: application/x-javascript; charset=UTF-8");

• unidentified changes in scrolling API that cause (on ne_10m_admin_0_countries imported) :

ERROR 1: {"error":{"root_cause":[{"type":"illegal_argument_exception","reason":"request _search/scroll contains unrecognized parameter: [size]"}],"type":"illegal_argument_exception","reason":"request _search/scroll contains unrecognized parameter: [size]"},"status":400}

[Even Rouault]

In 36733:

ElasticSearch: add ES 5.0 support, improve ES 2.X support and enforce read-only mode for layer operations (fixes #6724)