---
# Strategic-merge patch enabling node-exporter's textfile collector on
# the kube-prometheus-stack node-exporter DaemonSet (DEV-494).
#
# The chart is Helm-managed (release `kube-prometheus-stack` in
# namespace `observability`, chart kube-prometheus-stack-86.2.2 /
# prometheus-node-exporter-4.55.0) and is NOT currently tracked in
# ArgoCD, so a direct DaemonSet patch is the pragmatic wiring path.
# The change:
#
#   1. adds the `--collector.textfile.directory=/host/textfile_collector`
#      arg to the node-exporter container, and
#   2. mounts the host directory `/var/lib/node_exporter/textfile_collector`
#      read-only at `/host/textfile_collector` (type DirectoryOrCreate so
#      kubelet creates the dir on nodes where it does not yet exist).
#
# Apply with:
#   kubectl -n observability patch daemonset \
#     kube-prometheus-stack-prometheus-node-exporter \
#     --type=strategic \
#     --patch-file=apps/observability/patches/node-exporter-textfile-collector.yaml
#
# If the Helm release is ever `helm upgrade`d without folding these
# values into the chart values, this patch will be reverted — re-apply
# it after the upgrade (or move it into a repo-owned values file).
spec:
  template:
    spec:
      containers:
        - name: node-exporter
          args:
            - --path.procfs=/host/proc
            - --path.sysfs=/host/sys
            - --path.rootfs=/host/root
            - --path.udev.data=/host/root/run/udev/data
            - --web.listen-address=[$(HOST_IP)]:9100
            - --collector.filesystem.mount-points-exclude=^/(dev|proc|sys|run/containerd/.+|var/lib/docker/.+|var/lib/kubelet/.+)($|/)
            - --collector.filesystem.fs-types-exclude=^(autofs|binfmt_misc|bpf|cgroup2?|configfs|debugfs|devpts|devtmpfs|fusectl|hugetlbfs|iso9660|mqueue|nsfs|overlay|proc|procfs|pstore|rpc_pipefs|securityfs|selinuxfs|squashfs|sysfs|tracefs|erofs)$
            - --collector.textfile.directory=/host/textfile_collector
          volumeMounts:
            - mountPath: /host/proc
              name: proc
              readOnly: true
            - mountPath: /host/sys
              name: sys
              readOnly: true
            - mountPath: /host/root
              mountPropagation: HostToContainer
              name: root
              readOnly: true
            - mountPath: /host/textfile_collector
              name: textfile-collector
              readOnly: true
      volumes:
        - hostPath:
            path: /proc
            type: ""
          name: proc
        - hostPath:
            path: /sys
            type: ""
          name: sys
        - hostPath:
            path: /
            type: ""
          name: root
        - hostPath:
            path: /var/lib/node_exporter/textfile_collector
            type: DirectoryOrCreate
          name: textfile-collector