Partial shard failures rendered as non-structured exceptions

[clintongormley]

DELETE * 

PUT test/test/1
{
  "foz": "bar"
}

GET _search?sort=foo

Rendered as a structured exception:

{
   "error": {
      "root_cause": [
         {
            "type": "search_parse_exception",
            "reason": "No mapping found for [foo] in order to sort on"
         }
      ],
      "type": "search_phase_execution_exception",
      "reason": "all shards failed",
      "phase": "query",
      "grouped": true,
      "failed_shards": [
         {
            "shard": 0,
            "index": "test",
            "node": "v04p8T35S1ySNdsF9GTl7w",
            "reason": {
               "type": "search_parse_exception",
               "reason": "Failed to parse source [{\"sort\":[{\"foo\":{}}]}]",
               "caused_by": {
                  "type": "search_parse_exception",
                  "reason": "No mapping found for [foo] in order to sort on"
               }
            }
         }
      ]
   },
   "status": 400
}

However, if one shard succeeds, then exceptions are no longer structured:

PUT test2/test/1
{
  "foo": "bar"
}

GET _search?sort=foo

Renders as:

{
   "took": 3,
   "timed_out": false,
   "_shards": {
      "total": 10,
      "successful": 5,
      "failed": 5,
      "failures": [
         {
            "index": "test",
            "shard": 0,
            "status": 400,
            "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\":[{\"foo\":{}}]}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
         },
         {
            "index": "test",
            "shard": 1,
            "status": 400,
            "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\":[{\"foo\":{}}]}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
         },
         {
            "index": "test",
            "shard": 2,
            "status": 400,
            "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\":[{\"foo\":{}}]}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
         },
         {
            "index": "test",
            "shard": 3,
            "status": 400,
            "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\":[{\"foo\":{}}]}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
         },
         {
            "index": "test",
            "shard": 4,
            "status": 400,
            "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\":[{\"foo\":{}}]}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
         }
      ]
   },
   "hits": {
      "total": 1,
      "max_score": null,
      "hits": [
         {
            "_index": "test2",
            "_type": "test",
            "_id": "1",
            "_score": null,
            "_source": {
               "foo": "bar"
            },
            "sort": [
               "bar"
            ]
         }
      ]
   }
}

Similarly, errors in bulk APIs are not structured:

PUT test/test/_bulk
{"index": {"_id": 1 }}
{}
{"index": {"_id": 1 ,"_version": 2}}
{}

Returns:

{
   "took": 60,
   "errors": true,
   "items": [
      {
         "index": {
            "_index": "test",
            "_type": "test",
            "_id": "1",
            "_version": 1,
            "_shards": {
               "total": 2,
               "successful": 1,
               "failed": 0
            },
            "status": 201
         }
      },
      {
         "index": {
            "_index": "test",
            "_type": "test",
            "_id": "1",
            "status": 409,
            "error": "[test][3][test][1]: version conflict, current [1], provided [2]"
         }
      }
   ]
}

Curiously, _msearch doesn't return the reason if all shards failed:

GET _msearch
{"index": "test"}
{"sort": "foo"}
{"index": "_all"}
{"sort": "foo"}

Returns:

{
   "responses": [
      {
         "error": "SearchPhaseExecutionException[all shards failed]"
      },
      {
         "took": 6,
         "timed_out": false,
         "_shards": {
            "total": 10,
            "successful": 5,
            "failed": 5,
            "failures": [
               {
                  "index": "test",
                  "shard": 0,
                  "status": 400,
                  "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\": \"foo\"}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
               },
               {
                  "index": "test",
                  "shard": 1,
                  "status": 400,
                  "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\": \"foo\"}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
               },
               {
                  "index": "test",
                  "shard": 2,
                  "status": 400,
                  "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\": \"foo\"}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
               },
               {
                  "index": "test",
                  "shard": 3,
                  "status": 400,
                  "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\": \"foo\"}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
               },
               {
                  "index": "test",
                  "shard": 4,
                  "status": 400,
                  "reason": "RemoteTransportException[[Frigga][inet[/192.168.2.183:9300]][indices:data/read/search[phase/query]]]; nested: SearchParseException[Failed to parse source [{\"sort\": \"foo\"}]]; nested: SearchParseException[No mapping found for [foo] in order to sort on]; "
               }
            ]
         },
         "hits": {
            "total": 1,
            "max_score": null,
            "hits": [
               {
                  "_index": "test2",
                  "_type": "test",
                  "_id": "1",
                  "_score": null,
                  "_source": {
                     "foo": "bar"
                  },
                  "sort": [
                     "bar"
                  ]
               }
            ]
         }
      }
   ]
}