Introduce AutoMonitor for simpler enablement of Application Signals

[the-mann]

duplicate of: #297

Description of changes: Introduce Auto Monitor for Application Signals on K8s which provides an easier onboarding experience. When enabled, the Operator can auto-instrument K8s workloads that are associated with K8s services as they come up automatically without requiring explicit opt-in via workload specific annotations.

The operator now accepts a new arg auto-monitor-config that has the following structure:

{
  "monitorAllServices": false,
  "languages": [],
  "restartPods": false,
  "customSelector": {
    "java": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "python": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "dotnet": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "nodejs": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    }
  },
  "exclude": {
    "java": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "python": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "dotnet": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    },
    "nodejs": {
      "namespaces": [], "deployments": [], "daemonsets": [], "statefulsets": []
    }
  }
}

• monitorAllServices: Enable AutoMonitor for all services in the cluster i.e. for any K8s workloads that are brought up in the cluster, auto-instrument them. Defaults to false i.e. not enabled.
• langugages: Specify the list of languages that AutoMonitor should inject auto-instrumentation for. Defaults to all supported languages.
• restartPods: When enabled, restart pods that are already running on the cluster corresponding to K8s workloads that now fall under the scope of AutoMonitor. Defaults to false i.e. not enabled.
• customSelector: Provides more granular control to explicitly specify namespaces and workloads that should be auto-instrumented. Can be specified even if monitorAllServices is disabled.
• exclude: Similar to customSelector, but is instead used to deny specific namespaces or workloads from getting auto-instrumented when monitorAllServices is enabled. Takes precedence over customSelector in the case of conflicts.

Additional Notes:

• customSelector with restartPods enabled serves as a replacement for the existing auto-annotation-config arg. auto-annotation-config will be deprecated entirely in a future release. Using both is consider invalid and will continue to respect auto-annotation-config in such scenarios.
• monitorAllServices by default does not auto-instrument services in the kube-system and amazon-cloudwatch namespaces. If you require services in these namespaces to be auto-instrumented, you can explicitly specify them using customSelector.

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