Bulk request with empty body throws unhelpful error

[GamingCoder]

I came across this error in a script to automatically delete old entries. When no entries have to be deleted the script tried to do a bulk request with an empty array as body.

I created this script to show the error

var elasticsearch = require('elasticsearch');
var client = new elasticsearch.Client({
    host: 'localhost:9200',
    log: 'trace'
});
client.bulk({
    "body": []
}, function(err, resp) {
    if (err){
        console.trace(err);
    } else {
        console.log(resp);
    }
});

When running this script you get the following console output

Elasticsearch INFO: 2015-07-29T15:40:47Z
  Adding connection to http://localhost:9200/

Elasticsearch DEBUG: 2015-07-29T15:40:47Z
  starting request { method: 'POST',
    bulkBody: true,
    path: '/_bulk',
    body: [],
    query: {} }


Elasticsearch TRACE: 2015-07-29T15:40:47Z
  -> POST http://localhost:9200/_bulk

  <- 400
  {
    "error": "ElasticsearchParseException[Failed to derive xcontent from org.elasticsearch.common.bytes.BytesArray@1]",
    "status": 400
  }

Elasticsearch DEBUG: 2015-07-29T15:40:47Z
  Request complete

Trace: { [Error: ElasticsearchParseException[Failed to derive xcontent from org.elasticsearch.common.bytes.BytesArray@1]]
  status: '400',
  message: 'ElasticsearchParseException[Failed to derive xcontent from org.elasticsearch.common.bytes.BytesArray@1]' }
    at /tmp/tmp.fK3wh7WwBt/index.js:10:17
    at respond (/tmp/tmp.fK3wh7WwBt/node_modules/elasticsearch/src/lib/transport.js:251:9)
    at checkRespForFailure (/tmp/tmp.fK3wh7WwBt/node_modules/elasticsearch/src/lib/transport.js:200:7)
    at HttpConnector.<anonymous> (/tmp/tmp.fK3wh7WwBt/node_modules/elasticsearch/src/lib/connectors/http.js:155:7)
    at IncomingMessage.wrapper (/tmp/tmp.fK3wh7WwBt/node_modules/elasticsearch/node_modules/lodash/index.js:3095:19)
    at IncomingMessage.emit (events.js:117:20)
    at _stream_readable.js:943:16
    at process._tickCallback (node.js:419:13)

I run

• node v0.10.32
• ES client 5.0.0
• ES 1.6.0

[alanning]

A more descriptive error message would be nice. Perhaps something like, "Malformed body".

I just ran across this when the body field value was invalid:

EsClient.index({
      index: config.index,
      type: config.type,
      id: doc._id,
      body: doc  // <= ["xyz", {profile: {...}}]
    });

• ES 1.6.0
• npm javascript api v10.1.2

[spalger]

I agree, the error is not very clear about the actual problem and it is really unclear how to fix it. This error is not generated by elasticsearch-js though, it is sent from elasticsearch and provided to the user directly.

I suggest asking elasticsearch to provide a more informative error message.