400 Bad request for `indices.exists`

[tomaskallup]

🐛 Bug Report

I'm trying to create indices via the node js API, to make sure everything goes well, I fist do a check if the given index exists and send a delete to make sure it's not there. How ever for one index (not sure why only the one) the exists api throws 400 error with true in the body, this happens only if the index is already created.

Response example:

error ResponseError: Response Error
    at IncomingMessage.<anonymous> (/home/armeeh/Projects/Reas/reas-services/node_modules/@elastic/elasticsearch/lib/Transport.js:294:25)
    at IncomingMessage.emit (events.js:215:7)
    at endReadableNT (_stream_readable.js:1184:12)
    at processTicksAndRejections (internal/process/task_queues.js:80:21) {
  name: 'ResponseError',
  meta: {
    body: true,
    statusCode: 400,
    headers: {
      'content-type': 'text/plain; charset=utf-8',
      connection: 'close'
    },
    warnings: null,
    meta: {
      context: null,
      request: [Object],
      name: 'elasticsearch-js',
      connection: [Object],
      attempts: 0,
      aborted: false
    }
  }
}

Now I'm not really sure, if this is a error on the js part, or elastic itself, so please tell me and I'll recreate the issue accordingly.
Also a thing to add, using something like Postman or just simple curl and sending HEAD request to /streets (the one where it fails) I get the expected response (200 or 404).

To Reproduce

Steps to reproduce the behavior:

import { Client } from '@elastic/elasticsearch';

(async () => {
  // Elastic
  const cloudId = 'cloudId';
  const auth = {
    username: 'elastic',
    password: 'password',
  };

  const client = new Client({
    cloud: cloudId ? { id: cloudId, ...auth } : undefined,
    node:
      'url to cloud node',
    auth: cloudId ? undefined : auth,
  });

  for (const index of ['cities', 'streets']) {
    let exists = false;
    try {
      console.log('checking', index);
      // This throws the exception - only for 'streets' and only if they exist
      const existsResponse = await client.indices.exists({ index });
      exists = existsResponse.body;
    } catch (e) {
      console.log('error', e);
      debugger;
    }

    try {
      if (exists) {
        console.log('deleting', index);
        await client.indices.delete({
          method: 'DELETE',
          index,
        });
      }
    } catch (e) {
      console.log('error', e);
      debugger;
    }
  }

  try {
    await client.indices.create({
      index: 'streets',
      body: {
        settings: {
          analysis: {
            analyzer: {
              'my-asciifolding': {
                type: 'custom',
                tokenizer: 'standard',
                filter: ['standard', 'lowercase', 'asciifolding'],
              },
            },
          },
        },
        mappings: {
          properties: {
            city: {
              type: 'text',
              analyzer: 'my-asciifolding',
            },
            name: {
              type: 'text',
              analyzer: 'my-asciifolding',
            },
          },
        },
      },
    });
  } catch (e) {
    console.log('error', e);
    debugger;
  }

  try {
    await client.indices.create({
      index: 'cities',
      body: {
        settings: {
          analysis: {
            analyzer: {
              'my-asciifolding': {
                type: 'custom',
                tokenizer: 'standard',
                filter: ['standard', 'lowercase', 'asciifolding'],
              },
            },
          },
        },
        mappings: {
          properties: {
            name: {
              type: 'text',
              analyzer: 'my-asciifolding',
            },
          },
        },
      },
    });
  } catch (e) {
    console.log('error', e);
    debugger;
  }
})();

Expected behavior

I expect the method to return the correct response and not throw an exception.

Your Environment

• node version: v12.13.1
• @elastic/elasticsearch version: 7.5.0
• os: Linux
• Using the free trial of elasic cloud

[delvedor]

Hello! Are you using the default Elastic user?
I assume you are also using Elasticsearch v7.5 in Elastic Cloud :)

[tomaskallup]

@delvedor Yes, I'm using the default elastic user and version 7.5 in cloud.

[delvedor]

Hello!
I tried to reproduce your error, but I wasn't able to get the same result, but instead, I was getting a different error, still a 400.
After some debugging, I've noticed that every DELETE request sends an empty body that will be gzipped by the client by default when using Elastic Cloud.
If I disable the compression, the code works as expected, so probably the Elastic load balancer does not like the gzipped empty body.
I'll send a pr with a fix, in the meantime, you can create a new client instance with compression: false.