discovery.kubernetes "pods" {
  role = "pod"

  selectors {
    role  = "pod"
    field = "spec.nodeName=" + sys.env("HOSTNAME")
  }
}

discovery.relabel "pod_logs" {
  targets = discovery.kubernetes.pods.targets

  rule {
    source_labels = ["__meta_kubernetes_namespace"]
    target_label  = "namespace"
  }
  rule {
    source_labels = ["__meta_kubernetes_pod_name"]
    target_label  = "pod"
  }
  rule {
    source_labels = ["__meta_kubernetes_pod_container_name"]
    target_label  = "container"
  }
  rule {
    source_labels = ["__meta_kubernetes_pod_label_app_kubernetes_io_name"]
    regex         = "(.+)"
    target_label  = "app"
  }
  rule {
    source_labels = [
      "__meta_kubernetes_pod_label_app_kubernetes_io_name",
      "__meta_kubernetes_pod_label_app",
    ]
    separator   = ";"
    regex       = "^;(.+)$"
    replacement = "$1"
    target_label = "app"
  }
  rule {
    source_labels = [
      "__meta_kubernetes_pod_uid",
      "__meta_kubernetes_pod_container_name",
    ]
    separator   = "/"
    replacement = "/var/log/pods/*$1/*.log"
    target_label = "__path__"
  }
  rule {
    source_labels = ["__meta_kubernetes_pod_container_id"]
    regex         = `^(\S+):\/\/.+$`
    replacement   = "$1"
    target_label  = "container_runtime"
  }
}

local.file_match "pod_logs" {
  path_targets = discovery.relabel.pod_logs.output
}

loki.source.file "pod_logs" {
  targets    = local.file_match.pod_logs.targets
  forward_to = [loki.process.pod_logs.receiver]
}

loki.process "pod_logs" {
  stage.match {
    selector = `{container_runtime=~"containerd|cri-o"}`
    stage.cri {}
  }
  stage.match {
    selector = `{container_runtime="docker"}`
    stage.docker {}
  }

  stage.replace {
    expression = `(?i)"(?:authorization|bearer|jwt|password|passwd|client[_-]?secret)"\s*:\s*"([^"\\]*(?:\\.[^"\\]*)*)"`
    replace    = "[REDACTED]"
  }
  stage.replace {
    expression = `(?i)(?:authorization\s*[:=]\s*)(?:bearer\s+)?([A-Za-z0-9._~+/=-]+)`
    replace    = "[REDACTED]"
  }
  stage.replace {
    expression = `(?i)\bbearer\s+([A-Za-z0-9_-]+(?:\.[A-Za-z0-9_-]+){0,2})`
    replace    = "[REDACTED]"
  }
  stage.replace {
    expression = `(?i)(?:password|passwd|client[_-]?secret)\s*[:=]\s*([^\s"'{},]+)`
    replace    = "[REDACTED]"
  }

  stage.json {
    expressions = {
      level = "level",
    }
  }
  stage.labels {
    values = {
      level = "",
    }
  }
  stage.match {
    selector = `{level!~"(?i)^(trace|debug|info|warn|warning|error|fatal|panic)$"}`
    stage.label_drop {
      values = ["level"]
    }
  }
  stage.static_labels {
    values = {
      cluster = "home",
    }
  }
  stage.label_keep {
    values = ["cluster", "namespace", "app", "pod", "container", "level"]
  }

  forward_to = [loki.write.local.receiver]
}

loki.write "local" {
  endpoint {
    url                 = "http://loki.observability.svc.cluster.local:3100/loki/api/v1/push"
    batch_size          = "256KiB"
    batch_wait          = "1s"
    remote_timeout      = "10s"
    min_backoff_period  = "500ms"
    max_backoff_period  = "30s"
    max_backoff_retries = 10
  }
}

otelcol.receiver.otlp "traces" {
  grpc {
    endpoint = "0.0.0.0:4317"
  }

  output {
    traces = [otelcol.processor.k8sattributes.traces.input]
  }
}

otelcol.processor.k8sattributes "traces" {
  auth_type = "serviceAccount"

  extract {
    deployment_name_from_replicaset = false
    metadata = [
      "k8s.namespace.name",
      "k8s.deployment.name",
      "k8s.node.name",
      "k8s.pod.name",
      "k8s.pod.uid",
      "k8s.pod.start_time",
      "k8s.container.name",
    ]
  }

  pod_association {
    source {
      from = "resource_attribute"
      name = "k8s.pod.uid"
    }
  }
  pod_association {
    source {
      from = "resource_attribute"
      name = "k8s.pod.ip"
    }
  }
  pod_association {
    source {
      from = "connection"
    }
  }

  output {
    traces = [otelcol.processor.batch.traces.input]
  }
}

otelcol.processor.batch "traces" {
  timeout             = "1s"
  send_batch_size     = 512
  send_batch_max_size = 1024

  output {
    traces = [otelcol.exporter.otlp.tempo.input]
  }
}

otelcol.exporter.otlp "tempo" {
  client {
    endpoint = "tempo.observability.svc.cluster.local:4317"
    tls {
      insecure = true
    }
  }

  retry_on_failure {
    enabled          = true
    initial_interval = "1s"
    max_interval     = "15s"
    max_elapsed_time = "5m"
  }

  sending_queue {
    enabled           = true
    queue_size        = 256
    num_consumers     = 2
    sizer             = "requests"
    block_on_overflow = true
  }
}