--- title: file-logger keywords: - Apache APISIX - API Gateway - Plugin - File Logger description: This document contains information about the Apache APISIX file-logger Plugin. --- ## Description The `file-logger` Plugin is used to push log streams to a specific location. :::tip - `file-logger` plugin can count request and response data for individual routes locally, which is useful for [debugging](../debug-mode.md). - `file-logger` plugin can get [APISIX variables](../apisix-variable.md) and [NGINX variables](http://nginx.org/en/docs/varindex.html), while `access.log` can only use NGINX variables. - `file-logger` plugin support hot-loaded so that we can change its configuration at any time with immediate effect. - `file-logger` plugin saves every data in JSON format. - The user can modify the functions executed by the `file-logger` during the `log phase` to collect the information they want. ::: ## Attributes | Name | Type | Required | Description | | ---- | ------ | -------- | ------------- | | path | string | True | Log file path. | | log_format | object | False | Log format declared as key value pairs in JSON format. Values only support strings. [APISIX](../apisix-variable.md) or [Nginx](http://nginx.org/en/docs/varindex.html) variables can be used by prefixing the string with `$`. | | include_req_body | boolean | False | 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](https://github.com/api7/lua-resty-expr) for more. | | include_resp_body | boolean | False | When set to `true` includes the response body in the log file. | | include_resp_body_expr | array | False | When the `include_resp_body` attribute is set to `true`, use this to filter based on [lua-resty-expr](https://github.com/api7/lua-resty-expr). If present, only logs the response into file if the expression evaluates to `true`. | | match | array[array] | False | Logs will be recorded when the rule matching is successful if the option is set. See [lua-resty-expr](https://github.com/api7/lua-resty-expr#operator-list) for a list of available expressions. | ### Example of default log format ```json { "service_id": "", "apisix_latency": 100.99999809265, "start_time": 1703907485819, "latency": 101.99999809265, "upstream_latency": 1, "client_ip": "127.0.0.1", "route_id": "1", "server": { "version": "3.7.0", "hostname": "localhost" }, "request": { "headers": { "host": "127.0.0.1:1984", "content-type": "application/x-www-form-urlencoded", "user-agent": "lua-resty-http/0.16.1 (Lua) ngx_lua/10025", "content-length": "12" }, "method": "POST", "size": 194, "url": "http://127.0.0.1:1984/hello?log_body=no", "uri": "/hello?log_body=no", "querystring": { "log_body": "no" } }, "response": { "headers": { "content-type": "text/plain", "connection": "close", "content-length": "12", "server": "APISIX/3.7.0" }, "status": 200, "size": 123 }, "upstream": "127.0.0.1:1982" } ``` ## 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](../apisix-variable.md) or [Nginx](http://nginx.org/en/docs/varindex.html) variables can be used by prefixing the string with `$`. | 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: ```bash admin_key=$(yq '.deployment.admin.admin_key[0].key' conf/config.yaml | sed 's/"//g') ``` ::: ```shell curl http://127.0.0.1:9180/apisix/admin/plugin_metadata/file-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: ```shell {"host":"localhost","@timestamp":"2020-09-23T19:05:05-04:00","client_ip":"127.0.0.1","route_id":"1"} {"host":"localhost","@timestamp":"2020-09-23T19:05:05-04:00","client_ip":"127.0.0.1","route_id":"1"} ``` ## Enable Plugin The example below shows how you can enable the Plugin on a specific Route: ```shell curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -d ' { "plugins": { "file-logger": { "path": "logs/file.log" } }, "upstream": { "type": "roundrobin", "nodes": { "127.0.0.1:9001": 1 } }, "uri": "/hello" }' ``` ## Example usage Now, if you make a request, it will be logged in the path you specified: ```shell curl -i http://127.0.0.1:9080/hello ``` You will be able to find the `file.log` file in the configured `logs` directory. ## Filter logs ```shell curl http://127.0.0.1:9180/apisix/admin/routes/1 \ -H "X-API-KEY: $admin_key" -X PUT -d ' { "plugins": { "file-logger": { "path": "logs/file.log", "match": [ [ [ "arg_name","==","jack" ] ] ] } }, "upstream": { "type": "roundrobin", "nodes": { "127.0.0.1:9001": 1 } }, "uri": "/hello" }' ``` Test: ```shell curl -i http://127.0.0.1:9080/hello?name=jack ``` Log records can be seen in `logs/file.log`. ```shell curl -i http://127.0.0.1:9080/hello?name=rose ``` Log records cannot be seen in `logs/file.log`. ## Delete Plugin To remove the `file-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. ```shell 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": { "127.0.0.1:9001": 1 } } }' ```