Version: 3.11

clickhouse-logger

Description#

The clickhouse-logger Plugin is used to push logs to ClickHouse database.

Attributes#

Name	Type	Required	Default	Valid values	Description
endpoint_addr	Deprecated	True			Use `endpoint_addrs` instead. ClickHouse endpoints.
endpoint_addrs	array	True			ClickHouse endpoints.
database	string	True			Name of the database to store the logs.
logtable	string	True			Table name to store the logs.
user	string	True			ClickHouse username.
password	string	True			ClickHouse password.
timeout	integer	False	3	[1,...]	Time to keep the connection alive for after sending a request.
name	string	False	"clickhouse logger"		Unique identifier for the logger. If you use Prometheus to monitor APISIX metrics, the name is exported in `apisix_batch_process_entries`.
ssl_verify	boolean	False	true	[true,false]	When set to `true`, verifies SSL.
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 `$`.
include_req_body	boolean	False	false	[false, true]	When set to `true` includes the request body in the log. If the request body is too big to be kept in the memory, it can't be logged due to Nginx's limitations.
include_req_body_expr	array	False			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	False	false	[false, true]	When set to `true` includes the response body in the log.
include_resp_body_expr	array	False			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.

NOTE: encrypt_fields = {"password"} is also defined in the schema, which means that the field will be stored encrypted in etcd. See encrypted storage fields.

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#

{
    "response": {
        "status": 200,
        "size": 118,
        "headers": {
            "content-type": "text/plain",
            "connection": "close",
            "server": "APISIX/3.7.0",
            "content-length": "12"
        }
    },
    "client_ip": "127.0.0.1",
    "upstream_latency": 3,
    "apisix_latency": 98.999998092651,
    "upstream": "127.0.0.1:1982",
    "latency": 101.99999809265,
    "server": {
        "version": "3.7.0",
        "hostname": "localhost"
    },
    "route_id": "1",
    "start_time": 1704507612177,
    "service_id": "",
    "request": {
        "method": "POST",
        "querystring": {
            "foo": "unknown"
        },
        "headers": {
            "host": "localhost",
            "connection": "close",
            "content-length": "18"
        },
        "size": 110,
        "uri": "/hello?foo=unknown",
        "url": "http://localhost:1984/hello?foo=unknown"
    }
}

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 clickhouse-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/clickhouse-logger -H "X-API-KEY: $admin_key" -X PUT -d '
{
    "log_format": {
        "host": "$host",
        "@timestamp": "$time_iso8601",
        "client_ip": "$remote_addr"
    }
}'

You can use the clickhouse docker image to create a container like so:

docker run -d -p 8123:8123 -p 9000:9000 -p 9009:9009 --name some-clickhouse-server --ulimit nofile=262144:262144 clickhouse/clickhouse-server

Then create a table in your ClickHouse database to store the logs.

curl -X POST 'http://localhost:8123/' \
--data-binary 'CREATE TABLE default.test (host String, client_ip String, route_id String, service_id String, `@timestamp` String, PRIMARY KEY(`@timestamp`)) ENGINE = MergeTree()' --user default:

Enable Plugin#

If multiple endpoints are configured, they will be written randomly. The example below shows how you can enable the Plugin on a specific Route:

curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -d '
{
      "plugins": {
            "clickhouse-logger": {
                "user": "default",
                "password": "",
                "database": "default",
                "logtable": "test",
                "endpoint_addrs": ["http://127.0.0.1:8123"]
            }
       },
      "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 ClickHouse database:

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

Now, if you check for the rows in the table, you will get the following output:

curl 'http://localhost:8123/?query=select%20*%20from%20default.test'
127.0.0.1   127.0.0.1   1       2023-05-08T19:15:53+05:30

Delete Plugin#

To remove the clickhouse-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 '
{
    "uri": "/hello",
    "plugins": {},
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'