File Log

Append request and response data in JSON format to a log file. You can also specify streams (for example, /dev/stdout and /dev/stderr), which is especially useful when running Kong in Kubernetes.

This plugin uses blocking I/O, which could affect performance when writing to physical files on slow (spinning) disks.

Configuration Reference

You can configure this plugin using the Kong Admin API or through declarative configuration, which involves directly editing the Kong configuration file.

This plugin is compatible with requests with the following protocols:

• http
• https
• grpc
• grpcs

This plugin is compatible with DB-less mode.

In DB-less mode, Kong does not have an Admin API. If using this mode, configure the plugin using declarative configuration.

Enabling the plugin on a Service

$ curl -X POST http://<admin-hostname>:8001/services/<service>/plugins \
    --data "name=file-log"  \
    --data "config.path=/tmp/file.log"

apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: <file-log-example>
config: 
  path: /tmp/file.log
plugin: file-log

apiVersion: v1
kind: Service
metadata:
  name: <service>
  labels:
    app: <service>
  annotations:
    konghq.com/plugins: <file-log-example>
spec:
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP
    name: <service>
  selector:
    app: <service>

plugins:
- name: file-log
  service: <service>
  config: 
    path: /tmp/file.log

<service> is the id or name of the Service that this plugin configuration will target.

Enabling the plugin on a Route

$ curl -X POST http://<admin-hostname>:8001/routes/<route>/plugins \
    --data "name=file-log"  \
    --data "config.path=/tmp/file.log"

apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: <file-log-example>
config: 
  path: /tmp/file.log
plugin: file-log

apiVersion: networking/v1beta1
kind: Ingress
metadata:
  name: <route>
  annotations:
    kubernetes.io/ingress.class: kong
    konghq.com/plugins: <file-log-example>
spec:
  rules:
  - host: examplehostname.com
    http:
      paths:
      - path: /bar
        backend:
          serviceName: echo
          servicePort: 80

plugins:
- name: file-log
  route: <route>
  config: 
    path: /tmp/file.log

<route> is the id or name of the Route that this plugin configuration will target.

Enabling the plugin on a Consumer

$ curl -X POST http://<admin-hostname>:8001/consumers/<consumer>/plugins \
    --data "name=file-log"  \
    --data "config.path=/tmp/file.log"

apiVersion: configuration.konghq.com/v1
kind: KongPlugin
metadata:
  name: <file-log-example>
config: 
  path: /tmp/file.log
plugin: file-log

apiVersion: configuration.konghq.com/v1
kind: KongConsumer
metadata:
  name: <consumer>
  annotations:
    konghq.com/plugins: <file-log-example>
    kubernetes.io/ingress.class: kong

plugins:
- name: file-log
  consumer: <consumer>
  config: 
    path: /tmp/file.log

<consumer> is the id or username of the Consumer that this plugin configuration will target.

Enabling the plugin globally

A plugin which is not associated to any Service, Route, or Consumer is considered global, and will be run on every request. Read the Plugin Reference and the Plugin Precedence sections for more information.

$ curl -X POST http://<admin-hostname>:8001/plugins/ \
    --data "name=file-log"  \
    --data "config.path=/tmp/file.log"

apiVersion: configuration.konghq.com/v1
kind: KongClusterPlugin
metadata:
  name: <global-file-log>
  annotations:
    kubernetes.io/ingress.class: kong
  labels:
    global: \"true\"
config: 
  path: /tmp/file.log
plugin: file-log

plugins:
- name: file-log
  config: 
    path: /tmp/file.log

Parameters

Here's a list of all the parameters which can be used in this plugin's configuration:

Log Format

Every request will be logged separately in a JSON object separated by a new line \n, with the following format:

{
    "request": {
        "method": "GET",
        "uri": "/get",
        "url": "http://httpbin.org:8000/get",
        "size": "75",
        "querystring": {},
        "headers": {
            "accept": "*/*",
            "host": "httpbin.org",
            "user-agent": "curl/7.37.1"
        },
        "tls": {
            "version": "TLSv1.2",
            "cipher": "ECDHE-RSA-AES256-GCM-SHA384",
            "supported_client_ciphers": "ECDHE-RSA-AES256-GCM-SHA384",
            "client_verify": "NONE"
        }
    },
    "upstream_uri": "/",
    "response": {
        "status": 200,
        "size": "434",
        "headers": {
            "Content-Length": "197",
            "via": "kong/0.3.0",
            "Connection": "close",
            "access-control-allow-credentials": "true",
            "Content-Type": "application/json",
            "server": "nginx",
            "access-control-allow-origin": "*"
        }
    },
    "tries": [
        {
            "state": "next",
            "code": 502,
            "ip": "127.0.0.1",
            "port": 8000
        },
        {
            "ip": "127.0.0.1",
            "port": 8000
        }
    ],
    "authenticated_entity": {
        "consumer_id": "80f74eef-31b8-45d5-c525-ae532297ea8e",
        "id": "eaa330c0-4cff-47f5-c79e-b2e4f355207e"
    },
    "route": {
        "created_at": 1521555129,
        "hosts": null,
        "id": "75818c5f-202d-4b82-a553-6a46e7c9a19e",
        "methods": null,
        "paths": [
            "/example-path"
        ],
        "preserve_host": false,
        "protocols": [
            "http",
            "https"
        ],
        "regex_priority": 0,
        "service": {
            "id": "0590139e-7481-466c-bcdf-929adcaaf804"
        },
        "strip_path": true,
        "updated_at": 1521555129
    },
    "service": {
        "connect_timeout": 60000,
        "created_at": 1521554518,
        "host": "example.com",
        "id": "0590139e-7481-466c-bcdf-929adcaaf804",
        "name": "myservice",
        "path": "/",
        "port": 80,
        "protocol": "http",
        "read_timeout": 60000,
        "retries": 5,
        "updated_at": 1521554518,
        "write_timeout": 60000
    },
    "workspaces": [
        {
            "id":"b7cac81a-05dc-41f5-b6dc-b87e29b6c3a3",
            "name": "default"
        }
    ],
    "consumer": {
        "username": "demo",
        "created_at": 1491847011000,
        "id": "35b03bfc-7a5b-4a23-a594-aa350c585fa8"
    },
    "latencies": {
        "proxy": 1430,
        "kong": 9,
        "request": 1921
    },
    "client_ip": "127.0.0.1",
    "started_at": 1433209822425
}

A few considerations on the above JSON object:

• request contains properties about the request sent by the client
• response contains properties about the response sent to the client
• tries contains the list of (re)tries (successes and failures) made by the load balancer for this request
• route contains Kong properties about the specific Route requested
• service contains Kong properties about the Service associated with the requested Route
• authenticated_entity contains Kong properties about the authenticated credential (if an authentication plugin has been enabled)
• workspaces contains Kong properties of the Workspaces associated with the requested Route. Only in Kong Enterprise version >= 0.34.
• consumer contains the authenticated Consumer (if an authentication plugin has been enabled)
• latencies contains some data about the latencies involved:
  • proxy is the time it took for the final service to process the request
  • kong is the internal Kong latency that it took to run all the plugins
  • request is the time elapsed between the first bytes were read from the client and after the last bytes were sent to the client. Useful for detecting slow clients.
• client_ip contains the original client IP address
• started_at contains the UTC timestamp of when the request has started to be processed.

Kong Process Errors

This logging plugin will only log HTTP request and response data. If you are looking for the Kong process error file (which is the nginx error file), then you can find it at the following path: {prefix}/logs/error.log