GCP Stream Filter

A GCP stream doesn't tail a file - it holds a Cloud Logging filter. The editor builds that filter for you from structured controls under the Cloud Logging filter heading; a live Preview shows the exact query that will be sent to Cloud Logging as you change them.

Resource

The Google Cloud resource type to tail. A plain GCP Project source offers the full catalog:

Any - every log entry in the project (no resource constraint).
Serverless - Cloud Function, Cloud Run, App Engine.
Compute / containers - GCE Instance, GKE / Kubernetes Container, GKE Cluster.
Data - Cloud SQL Database, BigQuery, Dataflow Job.
Messaging / build - Pub/Sub Topic, Pub/Sub Subscription, Cloud Build.
Firebase - Firebase Auth, Firebase Hosting, Firebase Realtime Database.

(On a Firebase-project source this list is trimmed to the Firebase-relevant types; a GCP Project source like this one shows everything.)

Per-resource fields

Picking a resource reveals its narrowing fields - for example Service name + Location for Cloud Run, Function name + Region for Cloud Functions, or Cluster / Namespace / Container for GKE. Each is a combo box that suggests values discovered from your project: from recent log activity, and from Cloud Asset Inventory when your credentials carry roles/cloudasset.viewer. You can also type a value if it isn't listed, or leave a field blank to not constrain it.

A resource only produces output - and only suggests values - if your project actually logs it.

2nd-gen Cloud Functions run on Cloud Run, so their logs appear under the Cloud Run resource - not Cloud Function. Pick Cloud Run and set Service name to the function's name (lowercased). 1st-gen functions use Cloud Function + Function name.

Severity

Sets a severity>= floor - e.g. Warning keeps WARNING and above. Any applies no severity constraint.

Preview

The compiled, read-only filter. Empty means "tail every log entry in the project." A built filter looks like:

resource.type="cloud_run_revision" AND resource.labels.service_name="checkout" AND severity>=ERROR

The Test Cloud Logging Filter button runs ListLogEntries(pageSize: 1) with the compiled filter against the project. The result shows Filter works (✓) or Filter rejected (✗) with the specific API error.

The rest of the sheet

Name, the display Filter (wildcard pills applied to what's shown), Strip matched text, and Auto-stream at startup behave the same as any stream - see Streams. For setting up the GCP source itself (project ID, auth) and for reading structured GCP output, see GCP & Firebase Sources.