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Documentation Index

Fetch the complete documentation index at: https://docs.frankenpress.com/llms.txt

Use this file to discover all available pages before exploring further.

FrankenPress writes structured logs to stdout/stderr. Any cluster-side shipper that tails container streams (Vector, Grafana Alloy, Promtail, Datadog Agent, Fluent Bit) picks them up without pod-level config. The platform stays backend-neutral; you choose the destination.

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What’s emitted

StreamSourceFormatWhen
stdoutCaddy access logJSON, one line per requestAlways (public server only)
stderrPHP errorsPlain textAlways — php.ini error_log = /dev/stderr
stderrWordPress debug logPlain textOnly when WP_ENV=staging (routed to php://stderr)
The metrics server on FP_METRICS_PORT (default 9145) is not access-logged on purpose — Prometheus scrapes every ~15s would otherwise dominate the log stream. A Caddy access log line looks like: 
{"level":"info","ts":1778097120.412,"logger":"http.log.access.log0","msg":"handled request","request":{"remote_ip":"10.244.0.5","method":"GET","host":"fp-site.example.com","uri":"/2026/05/welcome/","headers":{"User-Agent":["Mozilla/5.0"]}},"bytes_read":0,"user_id":"","duration":0.0341,"size":18234,"status":200,"resp_headers":{"Content-Type":["text/html; charset=UTF-8"],"Cache-Status":["Souin; hit; ttl=287"]}}
The Cache-Status response header tells you whether Souin served from cache (hit) or fell through to PHP (miss). Vector is a vendor-neutral agent maintained by Datadog. A single DaemonSet ships to Loki, Datadog, both, or any other supported sink. This is the recommended path because it keeps the FrankenPress chart free of backend-specific glue.
1

Install the Vector Helm chart in DaemonSet mode

helm repo add vector https://helm.vector.dev
helm install vector vector/vector \
  --namespace observability --create-namespace \
  --set role=Agent \
  --values vector-values.yaml
2

Provide a `vector.yaml` config

The example below tails container logs cluster-wide, parses Caddy’s JSON access log, and ships to both Loki and Datadog. Drop whichever sink you don’t want.
vector-values.yaml
customConfig:
  data_dir: /vector-data-dir
  api:
    enabled: false

  sources:
    kubernetes:
      type: kubernetes_logs
      extra_label_selector: "app.kubernetes.io/name=fp-site"

  transforms:
    parse_caddy_json:
      type: remap
      inputs: [kubernetes]
      source: |
        # Caddy emits JSON on stdout; PHP/WP errors are plain on stderr.
        if .stream == "stdout" {
          parsed, err = parse_json(.message)
          if err == null {
            . = merge!(., parsed)
            .source_type = "caddy_access"
          }
        } else {
          .source_type = "php_error"
        }

  sinks:
    # Grafana Loki (Grafana Cloud or self-hosted)
    loki:
      type: loki
      inputs: [parse_caddy_json]
      endpoint: https://logs-prod-XXX.grafana.net
      auth:
        strategy: basic
        user: "${LOKI_USER}"
        password: "${LOKI_API_KEY}"
      labels:
        namespace: '{{ kubernetes.pod_namespace }}'
        pod: '{{ kubernetes.pod_name }}'
        source: '{{ source_type }}'
      encoding:
        codec: json

    # Datadog Logs
    datadog:
      type: datadog_logs
      inputs: [parse_caddy_json]
      default_api_key: "${DATADOG_API_KEY}"
      site: datadoghq.com
3

Verify in your backend

Generate traffic against the site, then check Loki Explore (filter {source="caddy_access"}) or Datadog Logs (source:caddy_access). You should see one entry per request with status, duration, uri, and resp_headers fields.
Vector’s kubernetes_logs source automatically picks up app.kubernetes.io/name=fp-site labels because the chart applies the standard Bitnami common labels. If you’ve overridden nameOverride, adjust the extra_label_selector.

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Alternative: Grafana Alloy / Promtail (Loki only)

If you’re a Loki-only shop and already run Grafana Alloy (or its predecessor Promtail), no FrankenPress-specific config is needed. The default discovery.kubernetes + loki.source.kubernetes pipeline tails all pod logs in the cluster. Filter by namespace or by the app.kubernetes.io/name=fp-site label in your Alloy config to scope to FrankenPress sites.

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Alternative: Datadog Agent (autodiscovery)

If you run the Datadog Agent DaemonSet with log autodiscovery, set pod annotations on the FrankenPress release: 
podAnnotations:
  ad.datadoghq.com/site.logs: |
    [{"source": "caddy", "service": "fp-site"}]
The site segment of the annotation key is the container name in the deployment template (it’s not configurable). The Datadog Agent will auto-tag each line with source:caddy and service:fp-site so its default Caddy log pipeline applies.

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What’s not shipped

  • Subchart logs. The chart’s bundled mariadb, redis, and minio subcharts each write their own logs to their own pod stdout. A cluster-side shipper picks those up automatically — they’re not FrankenPress’s concern. Production deploys typically disable the subcharts and use external services (RDS, DragonflyDB Operator, AWS S3) whose logs live wherever that operator/service writes them.
  • wp-cron Job logs. The wpCron CronJob writes to its own pod stdout; a DaemonSet-mode shipper captures those lines too.
  • Prometheus scrape access logs. Suppressed on purpose (see above). If you want them, add a log block inside the :{$FP_METRICS_PORT} server in a forked Caddyfile — but you almost certainly don’t.

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Failure modes

SymptomLikely cause
Only startup chatter in stdout, no per-request linesYou’re on an fp-runtime image older than the JSON-access-log change. Pull the latest tag and helm upgrade.
WP debug entries missing from logs in stagingWP_DEBUG_LOG was overridden to true (writes to disk); confirm it resolves to php://stderr in your config/environments/staging.php.
Vector / Alloy isn’t seeing the pod’s logsLabel selector mismatch — verify app.kubernetes.io/name=fp-site is present on the pod (`kubectl get pod -o yamlgrep -A1 labels`).
Cache-Status header missing from access log linesSouin only sets it on requests that flow through the cache directive. Logged-in / authenticated requests bypass cache by design and show no Cache-Status.