Logs Configuration #

This document walks you through how to configure the Logs feature.

What is a Logs? #

The Logs is a kwok Configuration that allows users to define and simulate logs to a single pod.

The YAML below shows all the fields of a Logs resource:

kind: Logs
apiVersion: kwok.x-k8s.io/v1alpha1
metadata:
  name: <string>
  namespace: <string>
spec:
  logs:
  - containers:
    - <string>
    logsFile: <string>
    previousLogsFile: <string>
    follow: <bool>

The logs simulation setting of a pod is specified via logs field. The previousLogsFile field specifies the file path of the previous terminated container logs. The logs field is organized by groups, with each corresponding to a collection of containers that shares a same logs simulation config. Each group consists of a list of container names (containers) and the shared simulation settings (logsFile and follow).

If containers is not given in a group, the logsFile and follow in that group will be applied to all containers of the target pod.

The logsFile field specifies the file path of the logs. If the logsFile field is not set, this item will be ignored. The follow field specifies whether to follow the logs. If the follow field is not set, the follow field will default to false.

ClusterLogs #

In addition to simulating a single pod, users can also simulate the logs for multiple pods via ClusterLogs.

The YAML below shows all the fields of a ClusterLogs resource:

kind: ClusterLogs
apiVersion: kwok.x-k8s.io/v1alpha1
metadata:
  name: <string>
spec:
  selector:
    matchNamespaces:
    - <string>
    matchNames:
    - <string>
  logs:
  - containers:
    - <string>
    logsFile: <string>
    previousLogsFile: <string>
    follow: <bool>

Compared to Logs, whose metadata.name and metadata.namespace are required to match the associated pod, ClusterLogs has an additional selector field for specifying the target pods to be simulated. matchNamespaces and matchNames are both represented as list，which are designed to take pod collections by different levels:

1. If matchNamespaces is empty, ClusterLogs will be applied to all pods that are managed by kwok and whose names listed in matchNames.
2. If matchNames is empty, ClusterLogs will be applied to all pods managed by kwok and under namespaces listed in matchNamespaces.
3. If matchNames and matchNamespaces are both unset, ClusterLogs will be applied to all pods that kwok manages.

The logs field of ClusterLogs has the same semantic with the one in Logs.

Examples #