kubeshark/agent/pkg/resolver/README.md
M. Mert Yıldıran 147e812edb
Replace all rlog occurrences with the shared logger (#350)
* Replace all `rlog` occurrences with the shared logger

* Use the same log format in `InitLoggerStderrOnly` as well

* Convert one more `log.Fatal` to `logger.Log.Errorf` as well in the `cli`

* Replace `log.` occurrences with `logger.Log.` in `agent`

* Fix `cannot use err (type error)`

* Change the logging level to `DEBUG`

* Replace an `Errorf` with `Fatal`

* Add informative message
2021-10-17 12:15:30 +03:00

2.1 KiB

Usage

Full example

errOut := make(chan error, 100)
k8sResolver, err := resolver.NewFromOutOfCluster("", errOut)
if err != nil {
    logger.Log.Errorf("error creating k8s resolver %s", err)
}

ctx, cancel := context.WithCancel(context.Background())
k8sResolver.Start(ctx)

resolvedName := k8sResolver.Resolve("10.107.251.91") // will always return `nil` in real scenarios as the internal map takes a moment to populate after `Start` is called
if resolvedName != nil {
    logger.Log.Errorf("resolved 10.107.251.91=%s", *resolvedName)
} else {
    logger.Log.Error("Could not find a resolved name for 10.107.251.91")
}

for {
    select {
        case err := <- errOut:
            logger.Log.Errorf("name resolving error %s", err)
    }
}

In cluster authentication

Create resolver using the function NewFromInCluster(errOut chan error)

Out of cluster authentication

Create resolver using the function NewFromOutOfCluster(kubeConfigPath string, errOut chan error)

the kubeConfigPath param is optional, pass an empty string "" for resolver to auto locate the default kubeconfig file

Error handling

Please ensure there is always a thread reading from the errOut channel, not doing so will result in the resolver threads getting blocked and the resolver will fail to update.

Also note that any error you receive through this channel does not necessarily mean that resolver is no longer running. the resolver will infinitely retry watching k8s resources until the provided context is cancelled.