API Stability Short-Term

The kafkaCluster() GraphQL query returns information on a Kafka cluster.

For information on Kafka, see the Kafka Configuration documentation page. You may also want to look at the Kafka Configuration reference page. For information on clusters in general, see the Cluster Management documentation page. Also, look at the LogScale Logical Architecture page in the Training section.

Syntax

graphql
kafkaCluster: KafkaClusterDescription

This query fiend has no input, just return values. For them, you can request the cluster's identifier, information on connected nodes, and log information. See the Return Datatype section for more possibilities.

Example

The example below queries LogScale with this query field:

Raw
graphql
query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}
Mac OS or Linux (curl)
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql \
    -H "Authorization: Bearer $TOKEN" \
    -H "Content-Type: application/json" \
    -d @- << EOF
{"query" : "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}"
}
EOF
Mac OS or Linux (curl) One-line
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql \
    -H "Authorization: Bearer $TOKEN" \
    -H "Content-Type: application/json" \
    -d @- << EOF
{"query" : "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}"
}
EOF
Windows Cmd and curl
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql ^
    -H "Authorization: Bearer $TOKEN" ^
    -H "Content-Type: application/json" ^
    -d @'{"query" : "query { ^
  kafkaCluster { ^
    clusterID, nodes { ^
    id, host, port},  ^
    logDirDescriptions { ^
      nodeID, path, error } } ^
}" ^
} '
Windows Powershell and curl
powershell
curl.exe -X POST 
    -H "Authorization: Bearer $TOKEN"
    -H "Content-Type: application/json"
    -d '{"query" : "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}"
}'
    "$YOUR_LOGSCALE_URL/graphql"
Perl
perl
#!/usr/bin/perl

use HTTP::Request;
use LWP;

my $TOKEN = "TOKEN";

my $uri = '$YOUR_LOGSCALE_URL/graphql';

my $query = "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}";
$query =~ s/\n/ /g;
my $json = sprintf('{"query" : "%s"}',$query);
my $req = HTTP::Request->new("POST", $uri );

$req->header("Authorization" => "Bearer $TOKEN");
$req->header("Content-Type" => "application/json");

$req->content( $json );

my $lwp = LWP::UserAgent->new;

my $result = $lwp->request( $req );

print $result->{"_content"},"\n";
Python
python
#! /usr/local/bin/python3

import requests

url = '$YOUR_LOGSCALE_URL/graphql'
mydata = r'''{"query" : "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}"
}'''

resp = requests.post(url,
                     data = mydata,
                     headers = {
   "Authorization" : "Bearer $TOKEN",
   "Content-Type" : "application/json"
}
)

print(resp.text)
Node.js
javascript
const https = require('https');

const data = JSON.stringify(
    {"query" : "query {
  kafkaCluster {
    clusterID, nodes {
    id, host, port}, 
    logDirDescriptions {
      nodeID, path, error } }
}"
}
);


const options = {
  hostname: '$YOUR_LOGSCALE_URL',
  path: 'graphql',
  port: 443,
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Content-Length': data.length,
    Authorization: 'BEARER ' + process.env.TOKEN,
    'User-Agent': 'Node',
  },
};

const req = https.request(options, (res) => {
  let data = '';
  console.log(`statusCode: ${res.statusCode}`);

  res.on('data', (d) => {
    data += d;
  });
  res.on('end', () => {
    console.log(JSON.parse(data).data);
  });
});

req.on('error', (error) => {
  console.error(error);
});

req.write(data);
req.end();
Example Responses
Success (HTTP Response Code 200 OK)
json
{
  "data": {
    "kafkaCluster": {
      "clusterID": "ExlWrS6RT1CmbCiP2TejTQ",
      "nodes": [
        {
          "id": 0,
          "host": "localhost",
          "port": 9092
        }
      ],
      "logDirDescriptions": [
        {
          "nodeID": 0,
          "path": "/data/kafka-data",
          "error": null
        }
      ]
    }
  }
}

Returned Datatype

The return datatype is used to get the cluster's unique identifier, information on connected nodes (e.g., the host and port used by each), log entries (e.g., error messages), and other Kafka data.

Table: KafkaClusterDescription

ParameterTypeRequiredDefaultStabilityDescription
Some arguments may be required, as indicated in the Required column. For return datatypes, this indicates that you must specify which fields you want returned in the results.
Table last updated: Sep 25, 2024
chatterTopicKafkaTopicDescriptionyes Short-TermAny chatter topic associated with the Kafka cluster. See KafkaTopicDescription.
clusterIDstringyes Short-TermThe unique identifier of the cluster.
controllerKafkaNodeyes Short-TermThe Kafka node that is the controller of the cluster. See KafkaNode.
globalEventsTopicKafkaTopicDescriptionyes Short-TermThe global Kafka events topic. See KafkaTopicDescription.
ingestTopicKafkaTopicDescriptionyes Short-TermA description of the Kafka ingest topic. See KafkaTopicDescription.
logDirDescriptions[KafkaLogDir]yes Short-TermDescriptions of the Kafka log directories. See KafkaLogDir.
nodes[KafkaNode]yes Short-TermThe list of Kafka nodes in the cluster. See KafkaNode.