clickhouse

Output plugin that inserts events into a ClickHouse table via the HTTP interface.

Inserts events into a ClickHouse table using the HTTP interface. Supports configurable input formats, DSN connection strings, and TLS.

Parameters

Parameter	Type	Default	Constraints	Description
`host`	string	—	Required. Non-empty.	ClickHouse server hostname or IP.
`port`	integer	`8123`	1–65535	HTTP/HTTPS port.
`protocol`	string	`"http"`	`"http"` or `"https"`	Connection protocol.
`database`	string	`"default"`	Non-empty.	Target database.
`table`	string	—	Required. Non-empty.	Target table.
`username`	string	`"default"`	Non-empty.	Authentication username.
`password`	string	`""`	—	Authentication password.
`dsn`	ClickHouse DSN or null	`null`	—	DSN string (e.g., `clickhouse+native://user:pass@host:9000/db`). Overrides individual connection fields.
`connect_timeout`	integer	`10`	>= 1	Connection timeout in seconds.
`request_timeout`	integer	`300`	>= 1	Full request timeout in seconds.
`client_name`	string or null	`null`	Non-empty if set.	Client name for the ClickHouse query log.
`verify`	boolean	`true`	—	Whether to verify the server's TLS certificate.
`ca_cert`	path or null	`null`	Non-empty if set.	Path to CA certificate file.
`client_cert`	path or null	`null`	Non-empty if set.	Path to client certificate. Must be provided together with `client_cert_key`.
`client_cert_key`	path or null	`null`	Non-empty if set.	Path to client certificate key. Must be provided together with `client_cert`.
`server_host_name`	string or null	`null`	Non-empty if set.	Expected server hostname in the TLS certificate.
`tls_mode`	string or null	`null`	`"proxy"`, `"strict"`, or `"mutual"`	TLS verification mode.
`proxy_url`	URL or null	`null`	Valid HTTP/HTTPS URL.	Proxy address.
`input_format`	string	`"JSONEachRow"`	Valid ClickHouse input format.	ClickHouse input format for the INSERT query.
`header`	string	`""`	—	String prepended before all events in each batch.
`footer`	string	`""`	—	String appended after all events in each batch.
`separator`	string	`"\n"`	—	String inserted between events.
`formatter`	formatter	`json`	—	How events are serialized before insertion.

Behavior

Events are sent via ClickHouse's raw insert API using the specified input_format.
The default combination of json formatter + JSONEachRow input format sends one JSON object per line.
For non-JSON formats (CSV, TabSeparated, etc.), use header, footer, and separator to control event wrapping and the plain formatter.
Connection via DSN overrides individual host, port, protocol, database, username, and password fields.

Examples

Basic JSONEachRow insertion:

output:
  - clickhouse:
      host: clickhouse.example.com
      database: analytics
      table: events
      username: ${params.ch_user}
      password: ${secrets.ch_password}

HTTPS with custom port:

output:
  - clickhouse:
      host: clickhouse.prod
      port: 8443
      protocol: https
      database: analytics
      table: events
      verify: true
      input_format: JSONEachRow

Via DSN string:

output:
  - clickhouse:
      dsn: clickhouse+native://admin:secret@clickhouse.prod:9000/analytics
      table: events

CSV input format with plain formatter:

output:
  - clickhouse:
      host: localhost
      table: events
      input_format: CSV
      separator: "\n"
      formatter:
        format: plain

clickhouse

Parameters

Behavior

Examples

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