udp-logger

Description

The udp-logger Plugin can be used to push log data requests to UDP servers.

This provides the ability to send log data requests as JSON objects to monitoring tools and other UDP servers.

This plugin also allows to push logs as a batch to your external UDP server. It might take some time to receive the log data. It will be automatically sent after the timer function in the batch processor expires.

Attributes

Name	Type	Required	Default	Valid values	Description
host	string	True			IP address or the hostname of the UDP server.
port	integer	True		[0,…]	Target upstream port.
timeout	integer	False	3	[1,…]	Timeout for the upstream to send data.
log_format	object	False			Log format declared as key value pairs in JSON format. Values only support strings. APISIX or Nginx variables can be used by prefixing the string with `$`.
name	string	False	“udp logger”		Unique identifier for the batch processor. If you use Prometheus to monitor APISIX metrics, the name is exported in `apisix_batch_process_entries`. processor.
include_req_body	boolean	False	false	[false, true]	When set to `true` includes the request body in the log.
include_req_body_expr	array	No			Filter for when the `include_req_body` attribute is set to `true`. Request body is only logged when the expression set here evaluates to `true`. See lua-resty-expr for more.
include_resp_body	boolean	No	false	[false, true]	When set to `true` includes the response body in the log.
include_resp_body_expr	array	No			Filter for when the `include_resp_body` attribute is set to `true`. Response body is only logged when the expression set here evaluates to `true`. See lua-resty-expr for more.

This Plugin supports using batch processors to aggregate and process entries (logs/data) in a batch. This avoids the need for frequently submitting the data. The batch processor submits data every 5 seconds or when the data in the queue reaches 1000. See Batch Processor for more information or setting your custom configuration.

Example of default log format

{
  "apisix_latency": 99.999988555908,
  "service_id": "",
  "server": {
    "version": "3.7.0",
    "hostname": "localhost"
  },
  "request": {
    "method": "GET",
    "headers": {
      "connection": "close",
      "host": "localhost"
    },
    "url": "http://localhost:1984/opentracing",
    "size": 65,
    "querystring": {},
    "uri": "/opentracing"
  },
  "start_time": 1704527399740,
  "client_ip": "127.0.0.1",
  "response": {
    "status": 200,
    "size": 136,
    "headers": {
      "server": "APISIX/3.7.0",
      "content-type": "text/plain",
      "transfer-encoding": "chunked",
      "connection": "close"
    }
  },
  "upstream": "127.0.0.1:1982",
  "route_id": "1",
  "upstream_latency": 12,
  "latency": 111.99998855591
}

Metadata

You can also set the format of the logs by configuring the Plugin metadata. The following configurations are available:

Name	Type	Required	Default	Description
log_format	object	False		Log format declared as key value pairs in JSON format. Values only support strings. APISIX or Nginx variables can be used by prefixing the string with `$`.

IMPORTANT

Configuring the Plugin metadata is global in scope. This means that it will take effect on all Routes and Services which use the udp-logger Plugin.

The example below shows how you can configure through the Admin API:

note

You can fetch the admin_key from config.yaml and save to an environment variable with the following command:

admin_key=$(yq '.deployment.admin.admin_key[0].key' conf/config.yaml | sed 's/"//g')

curl http://127.0.0.1:9180/apisix/admin/plugin_metadata/udp-logger -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "log_format": {
        "host": "$host",
        "@timestamp": "$time_iso8601",
        "client_ip": "$remote_addr"
    }
}'

With this configuration, your logs would be formatted as shown below:

{"@timestamp":"2023-01-09T14:47:25+08:00","route_id":"1","host":"localhost","client_ip":"127.0.0.1"}

Enable Plugin

The example below shows how you can enable the Plugin on a specific Route:

curl http://127.0.0.1:9180/apisix/admin/routes/5 -H "X-API-KEY: $admin_key" -X PUT -d '
{
      "plugins": {
            "udp-logger": {
                 "host": "127.0.0.1",
                 "port": 3000,
                 "batch_max_size": 1,
                 "name": "udp logger"
            }
       },
      "upstream": {
           "type": "roundrobin",
           "nodes": {
               "127.0.0.1:1980": 1
           }
      },
      "uri": "/hello"
}'

Example usage

Now, if you make a request to APISIX, it will be logged in your UDP server:

curl -i http://127.0.0.1:9080/hello

Delete Plugin

To remove the udp-logger Plugin, you can delete the corresponding JSON configuration from the Plugin configuration. APISIX will automatically reload and you do not have to restart for this to take effect.

curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "methods": ["GET"],
    "uri": "/hello",
    "plugins": {},
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'