examples: kubernetes: add more explanation about inclusion/exclusion …

…logs

Signed-off-by: Dominik Rosiek <[email protected]>

examples/kubernetes/README.md

@@ -8,6 +8,23 @@ This demo is a sample app to build the collector and exercise its kubernetes log
 
 Switch to this directory and run following command: `kubectl apply -n <namespace> -f otel-collector.yaml`
 
+#### Include/Exclude Specific Logs
+
+Kubernetes logs are being stored in `/var/log/pods`.
+Path to container logs is constructed using following pattern:
+
+`/var/log/pods/<namespace>_<pod_name>_<pod_uid>/<container>/<run_id>.log`
+
+You can use it to manage from which containers do you want to include and exclude logs.
+
+For example, to include all logs from `default` namespace, you can use following configuration:
+
+```yaml
+include:
+    - /var/log/pods/default_*/*/*.log
+exclude: []
+```
+
 ### Docker Compose
 
 Two steps are required to build and run the demo:

examples/kubernetes/otel-collector-config.yml

@@ -1,10 +1,9 @@
 receivers:
   filelog:
     include:
-      # - /var/log/pods/namespace_pod-name_pod-uid/container-name/*.log
       - /var/log/pods/*/*/*.log
     exclude:
-      # - /var/log/pods/namespace_pod-name_pod-uid/container-name/*.log
+      # Exclude logs from all containers named otel-collector
       - /var/log/pods/*/otel-collector/*.log
     start_at: beginning
     include_file_path: true

examples/kubernetes/otel-collector.yaml

@@ -8,10 +8,9 @@ data:
     receivers:
       filelog:
         include:
-          # - /var/log/pods/namespace_pod-name_pod-uid/container-name/*.log
           - /var/log/pods/*/*/*.log
         exclude:
-          # - /var/log/pods/namespace_pod-name_pod-uid/container-name/*.log
+          # Exclude logs from all containers named otel-collector
           - /var/log/pods/*/otel-collector/*.log
         start_at: beginning
         include_file_path: true

examples/kubernetes/varlogpods/otel_otel_888877776666555544443333222211110000/otel-collector/0.log

@@ -0,0 +1,7 @@
+2021-02-16T09:21:15.518430714Z stdout F otel-collector: 10 Tue Feb 16 09:21:15 UTC 2021
+2021-02-16T09:21:16.519721603Z stdout F otel-collector: 11 Tue Feb 16 09:21:16 UTC 2021
+2021-02-16T09:21:17.521307236Z stdout F otel-collector: 12 Tue Feb 16 09:21:17 UTC 2021
+2021-02-16T09:21:18.522445945Z stdout F otel-collector: 13 (part of log) Tue Feb 16 09:21:18 UTC 2021
+2021-02-16T09:21:18.522445945Z stdout F otel-collector: 13 (end of log) Tue Feb 16 09:21:18 UTC 2021
+2021-02-16T09:21:19.523759881Z stdout F otel-collector: 14 Tue Feb 16 09:21:19 UTC 2021
+2021-02-16T09:21:20.545525544Z stdout F otel-collector: 15 Tue Feb 16 09:21:20 UTC 2021