---

title: kafka-logger

Summary

• Name
• Attributes
• Info
• How To Enable
• Test Plugin
• Disable Plugin

Name

kafka-logger is a plugin which works as a Kafka client driver for the ngx_lua nginx module.

This will provide the ability to send Log data requests as JSON objects to external Kafka clusters.

This plugin provides the ability to push Log data as a batch to you‘re external Kafka topics. In case if you did not receive the log data don’t worry give it some time it will automatically send the logs after the timer function expires in our Batch Processor.

For more info on Batch-Processor in Apache APISIX please refer. Batch-Processor

Attributes

Name	Type	Requirement	Default	Valid	Description
broker_list	object	required			An array of Kafka brokers.
kafka_topic	string	required			Target topic to push data.
producer_type	string	optional	async	[“async”, “sync”]	Producer's mode of sending messages.
key	string	optional			Used for partition allocation of messages.
timeout	integer	optional	3	[1,...]	Timeout for the upstream to send data.
name	string	optional	“kafka logger”		A unique identifier to identity the batch processor.
meta_format	enum	optional	“default”	[“default”，“origin”]	default: collect the request information with default JSON way. origin: collect the request information with original HTTP request. example
batch_max_size	integer	optional	1000	[1,...]	Set the maximum number of logs sent in each batch. When the number of logs reaches the set maximum, all logs will be automatically pushed to the Kafka service.
inactive_timeout	integer	optional	5	[1,...]	The maximum time to refresh the buffer (in seconds). When the maximum refresh time is reached, all logs will be automatically pushed to the Kafka service regardless of whether the number of logs in the buffer reaches the set maximum number.
buffer_duration	integer	optional	60	[1,...]	Maximum age in seconds of the oldest entry in a batch before the batch must be processed.
max_retry_count	integer	optional	0	[0,...]	Maximum number of retries before removing from the processing pipe line.
retry_delay	integer	optional	1	[0,...]	Number of seconds the process execution should be delayed if the execution fails.
include_req_body	boolean	optional	false	[false, true]	Whether to include the request body. false: indicates that the requested body is not included; true: indicates that the requested body is included.

examples of meta_format

• default:

  {
   "upstream": "127.0.0.1:1980",
   "start_time": 1619414294760,
   "client_ip": "127.0.0.1",
   "service_id": "",
   "route_id": "1",
   "request": {
     "querystring": {
       "ab": "cd"
     },
     "size": 90,
     "uri": "/hello?ab=cd",
     "url": "http://localhost:1984/hello?ab=cd",
     "headers": {
       "host": "localhost",
       "content-length": "6",
       "connection": "close"
     },
     "body": "abcdef",
     "method": "GET"
   },
   "response": {
     "headers": {
       "connection": "close",
       "content-type": "text/plain; charset=utf-8",
       "date": "Mon, 26 Apr 2021 05:18:14 GMT",
       "server": "APISIX/2.5",
       "transfer-encoding": "chunked"
     },
     "size": 190,
     "status": 200
   },
   "server": {
     "hostname": "localhost",
     "version": "2.5"
   },
   "latency": 0
  }
  

• origin:

  GET /hello?ab=cd HTTP/1.1
  host: localhost
  content-length: 6
  connection: close
  
  abcdef
  

Info

The message will write to the buffer first. It will send to the kafka server when the buffer exceed the batch_max_size, or every buffer_duration flush the buffer.

In case of success, returns true. In case of errors, returns nil with a string describing the error (buffer overflow).

Sample broker list

This plugin supports to push in to more than one broker at a time. Specify the brokers of the external kafka servers as below sample to take effect of this functionality.

{
    "127.0.0.1":9092,
    "127.0.0.1":9093
}

How To Enable

The following is an example on how to enable the kafka-logger for a specific route.

curl http://127.0.0.1:9080/apisix/admin/routes/5 -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
{
    "plugins": {
       "kafka-logger": {
           "broker_list" :
             {
               "127.0.0.1":9092
             },
           "kafka_topic" : "test2",
           "key" : "key1",
           "batch_max_size": 1,
           "name": "kafka logger"
       }
    },
    "upstream": {
       "nodes": {
           "127.0.0.1:1980": 1
       },
       "type": "roundrobin"
    },
    "uri": "/hello"
}'

Test Plugin

*success:

$ curl -i http://127.0.0.1:9080/hello
HTTP/1.1 200 OK
...
hello, world

Disable Plugin

Remove the corresponding json configuration in the plugin configuration to disable the kafka-logger. APISIX plugins are hot-reloaded, therefore no need to restart APISIX.

$ curl http://127.0.0.1:2379/apisix/admin/routes/1  -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d value='
{
    "methods": ["GET"],
    "uri": "/hello",
    "plugins": {},
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'