indritvaka/pubsub-emulator-console repository overview

⁠pubsub-emulator-console

A single-container web console for a Google Pub/Sub emulator. Publish, peek (non-destructive), pull, ack (delete) / nack (requeue), purge, and manage topics and subscriptions. Built for local development — no auth, localhost only.

⁠Ports

The console listens on 8680.

Why the emulator is on 8086 rather than Google's documented default of 8085: gcloud already uses 8085 itself — gcloud auth login starts a local callback server on that port to complete the browser sign-in flow. An emulator sitting on 8085 clashes with it, so everything here defaults to 8086 instead. If you do run the emulator on 8085, just point the console at it: PUBSUB_EMULATOR_HOST=localhost:8085.

⁠Run

docker run -d -p 127.0.0.1:8680:8680 \
  -e PUBSUB_EMULATOR_HOST=<emulator-host>:8086 \
  -e GCP_PROJECT_IDS=local-dev \
  indritvaka/pubsub-emulator-console:latest

Open http://localhost:8680⁠.

⁠Docker Compose

Point the console at the emulator by service name (pubsub-emulator:8086), not localhost:8086.

services:
  pubsub-emulator:
    image: gcr.io/google.com/cloudsdktool/google-cloud-cli:emulators
    container_name: pubsub-emulator
    ports:
      - "8086:8086"
    environment:
      CLOUDSDK_CORE_DISABLE_FILE_LOGGING: "true"
    command: >
      gcloud beta emulators pubsub start
      --host-port=0.0.0.0:8086
      --project=local-dev
    healthcheck:
      test: ["CMD-SHELL", "curl -sf http://localhost:8086 || exit 1"]
      interval: 5s
      timeout: 3s
      retries: 12
      start_period: 10s
    networks:
      - pubsub-network

  pubsub-console:
    image: ${PUBSUB_UI_IMAGE:-indritvaka/pubsub-emulator-console:latest}
    container_name: pubsub-console
    depends_on:
      pubsub-emulator:
        condition: service_healthy
    ports:
      - "127.0.0.1:${PUBSUB_UI_PORT:-8680}:8680"
    environment:
      PUBSUB_EMULATOR_HOST: pubsub-emulator:8086
      GCP_PROJECT_IDS: local-dev
    networks:
      - pubsub-network

networks:
  pubsub-network:

⁠Configuration

⁠Tags

• latest — most recent tagged release
• vX.Y.Z — a specific release
• main — built from the tip of the default branch

⁠What it does

This project exists because the Pub/Sub emulator UIs available at the time were mostly read-only: they showed topics, subscriptions and message state, but not the operations you actually need while developing — no non-destructive peek, no pull workflow, no purge, no quick create/delete of topics and subscriptions.

• Publish messages to topics
• Peek messages non-destructively
• Pull messages from subscriptions
• Ack messages
• Nack / requeue messages
• Bulk-select messages (select-all) to ack or nack in one click
• Copy a message body to the clipboard
• "Quick use" a pulled message to pre-fill the publish form on its topic
• Keep an unsent publish draft per topic, so a half-written message (data, attributes, ordering key) survives navigating away, or a page reload
• "Keep values after publishing" to resend the same message without retyping it
• Purge subscription backlogs
• Create and delete topics
• Create and delete subscriptions
• View topic → subscription relationships

The image bundles a React frontend with an Express backend that serves the UI and proxies browser requests to the emulator API.

⁠Screenshots

Topic view — compose a message with attributes and an ordering key, keep the values to resend, and see the subscriptions attached to the topic:

Subscription view — peek or pull, then ack, nack or purge; select rows to act on them in bulk, or copy and "quick use" a single message:

⁠Limitations

The emulator does not expose exact backlog/undelivered counts (a Cloud Monitoring metric, absent locally). The console shows the count of messages a peek/pull returned, never a fabricated "N in backlog" badge.

Ordering keys are passed through and displayed faithfully, but subscriptions created here are not made ordering-enabled, so ordered delivery is not guaranteed for console-created subscriptions.

⁠Links

• Source: https://github.com/Indrit-Vaka/pubsub-emulator-console⁠
• Issues: https://github.com/Indrit-Vaka/pubsub-emulator-console/issues⁠
• Docs: https://github.com/Indrit-Vaka/pubsub-emulator-console#readme⁠

MIT-licensed. Created and maintained by Indrit Vaka⁠.