Skip to main content

​
Overview

The SYNQ Google Cloud Pub/Sub integration automatically discovers all Pub/Sub topics and subscriptions in your Google Cloud project and creates custom entities in SYNQ for centralized asset management, governance, and cross-platform data lineage. This integration can also serve as a reference implementation for building custom integrations using the SYNQ Public API. Source code: github.com/getsynq/synq-google-cloud-pubsub

​
What It Does

The integration:
  • Discovers all Pub/Sub topics and subscriptions in your GCP project
  • Creates custom entities in SYNQ for each resource
  • Tracks relationships between topics and their subscriptions (optional)
  • Automatically cleans up entities when resources are deleted
  • Supports flexible filtering with include/exclude patterns

​
Use Cases

  • Data Catalog Management: Track all messaging infrastructure in one place
  • Resource Discovery: Automatically maintain an up-to-date inventory
  • Compliance Tracking: Monitor messaging configurations and subscriptions
  • Cross-Platform Lineage: Connect Pub/Sub topics with data pipelines, BigQuery tables, and other systems

​
Installation

​
Download Pre-built Binaries

Download the latest release for your platform from the releases page.
Intel:
curl -LO https://github.com/getsynq/synq-google-cloud-pubsub/releases/latest/download/synq-google-cloud-pubsub_darwin_amd64.tar.gz
tar -xzf synq-google-cloud-pubsub_darwin_amd64.tar.gz
sudo mv synq-google-cloud-pubsub /usr/local/bin/
Apple Silicon:
curl -LO https://github.com/getsynq/synq-google-cloud-pubsub/releases/latest/download/synq-google-cloud-pubsub_darwin_arm64.tar.gz
tar -xzf synq-google-cloud-pubsub_darwin_arm64.tar.gz
sudo mv synq-google-cloud-pubsub /usr/local/bin/
AMD64:
curl -LO https://github.com/getsynq/synq-google-cloud-pubsub/releases/latest/download/synq-google-cloud-pubsub_linux_amd64.tar.gz
tar -xzf synq-google-cloud-pubsub_linux_amd64.tar.gz
sudo mv synq-google-cloud-pubsub /usr/local/bin/
ARM64:
curl -LO https://github.com/getsynq/synq-google-cloud-pubsub/releases/latest/download/synq-google-cloud-pubsub_linux_arm64.tar.gz
tar -xzf synq-google-cloud-pubsub_linux_arm64.tar.gz
sudo mv synq-google-cloud-pubsub /usr/local/bin/
Download the .zip file from the releases page and extract it.
Requires Go 1.24 or later:
git clone https://github.com/getsynq/synq-google-cloud-pubsub.git
cd synq-google-cloud-pubsub
go build

​
Configuration

​
Required: SYNQ API Credentials

Create a .env file with your SYNQ API credentials: 
SYNQ_CLIENT_ID=your_client_id_here
SYNQ_CLIENT_SECRET=your_client_secret_here

# GCP Project ID (optional if running on GCP or using gcloud)
GCP_PROJECT_ID=your-gcp-project-id
The GCP project ID can be auto-detected from:
  • Environment variables (GCP_PROJECT_ID, GOOGLE_CLOUD_PROJECT, GCLOUD_PROJECT)
  • gcloud CLI configuration
  • GCP metadata server (when running on GCP)

​
Optional: Advanced Configuration

For advanced customization, create a config.yaml file: 
# SYNQ API Configuration (defaults shown for EU region)
synq:
  endpoint: "developer.synq.io:443"  # EU region (default)
  # For US region, use: "api.us.synq.io:443"
  oauth_url: "https://developer.synq.io/oauth2/token"  # EU region (default)
  # For US region, use: "https://api.us.synq.io/oauth2/token"

# GCP Configuration
gcp:
  user_agent: "synq-pubsub-client-v1.0.0"
  # project_id: "your-project-id"  # Alternative to GCP_PROJECT_ID env var
  # entity_group_id: "pubsub::custom-group-id"  # Defaults to pubsub::<project_id>

# Custom Entity Type IDs
types:
  topic_type_id: 20
  subscription_type_id: 21
  # topic_icon: "path/to/custom-topic-icon.svg"
  # subscription_icon: "path/to/custom-subscription-icon.svg"

# Resource Filters
filter:
  topics:
    include: []  # Empty means include all
    exclude: []  # Regex patterns to exclude

  subscriptions:
    include: []  # Empty means include all
    exclude:
      # Exclude auto-generated per-pod subscriptions
      - '-[a-z0-9]{9,10}-[a-z0-9]{5}\.subscription$'

# Relationship Management (disabled by default)
relationships:
  enabled: false  # Set to true to enable topic->subscription relationships
  filter:
    include: []  # Empty means include all (format: "topic_id->subscription_id")
    exclude: []  # Regex patterns to exclude relationship pairs
    # Examples:
    # include: ["important-topic->.*"]  # Only relationships for important-topic
    # exclude: ["test-.*->.*"]          # Skip relationships for test topics
Configuration precedence: defaults → config.yaml → environment variables → CLI flags

​
Network Requirements

If your GCP project has firewall rules that restrict outbound connections, whitelist SYNQ’s egress IP addresses:
See IP Addresses for the latest information.

​
Running the Integration

​
Basic Usage

# Minimal setup: just create .env with credentials
cp .env.example .env
# Edit .env and add your credentials

# Run with defaults
./synq-google-cloud-pubsub

# Run with debug logging
LOG_LEVEL=DEBUG ./synq-google-cloud-pubsub

# Run with JSON logging for production
LOG_FORMAT=json ./synq-google-cloud-pubsub

​
Enabling Relationships

To track relationships between topics and subscriptions: 
# Enable relationships via command-line
./synq-google-cloud-pubsub --relationships.enabled

# Or configure in config.yaml
# relationships:
#   enabled: true
Relationships are disabled by default. Enable them only if you need to track topic-to-subscription connections in your data lineage.

​
Dry-Run Mode

Preview what entities would be created without making API calls: 
# Dry-run mode (no SYNQ API calls)
./synq-google-cloud-pubsub --dry-run

# Dry-run with debug logging and relationships
LOG_LEVEL=DEBUG ./synq-google-cloud-pubsub --dry-run --relationships.enabled
In dry-run mode, the integration scans Pub/Sub resources and shows what would be created, but does not call the SYNQ API or require credentials.

​
Command-Line Options

Common flags:
  • --dry-run - Preview changes without calling SYNQ API
  • --gcp.project-id - Specify GCP project ID
  • --relationships.enabled - Enable topic-to-subscription relationships
  • --filter.topics.include - Topic name patterns to include
  • --filter.topics.exclude - Topic name patterns to exclude
  • --filter.subscriptions.include - Subscription name patterns to include
  • --filter.subscriptions.exclude - Subscription name patterns to exclude
  • --types.topic-type-id - Custom entity type ID for topics (default: 20)
  • --types.subscription-type-id - Custom entity type ID for subscriptions (default: 21)
  • --synq.endpoint - SYNQ API endpoint (EU or US region)
For US region: 
./synq-google-cloud-pubsub \
  --synq.endpoint=api.us.synq.io:443 \
  --synq.oauth-url=https://api.us.synq.io/oauth2/token
Run ./synq-google-cloud-pubsub --help for all available options.

​
How It Works

  1. Authenticates with SYNQ API using OAuth2 client credentials
  2. Creates/updates custom entity types for topics and subscriptions
  3. Discovers all Pub/Sub topics and subscriptions in your project
  4. Creates entities in SYNQ for each resource
  5. Manages relationships between topics and subscriptions (if enabled)
  6. Uses entity groups to enable automatic cleanup of deleted resources

​
Entity Groups

The integration uses entity groups to track all entities created in each run. When the group is updated, SYNQ automatically removes entities that were in the previous group but not in the current one, enabling automatic cleanup of deleted resources.

​
Relationship Management

When enabled, the integration creates relationships between topics and their subscriptions. The system:
  • Deduplicates relationships to avoid recreating existing ones
  • Cleans up relationships that no longer exist
  • Supports filtering with include/exclude patterns

​
Custom Identifiers

All entities use custom identifiers with pubsub:: prefix for namespace isolation. Subscriptions use composite identifiers: pubsub::<topic_id>::<subscription_id>.

​
Scheduling with Cron

To keep your Pub/Sub inventory up-to-date, schedule the integration to run periodically: 
# Run every hour
0 * * * * cd /path/to/integration && ./synq-google-cloud-pubsub

# Run every 6 hours with relationships
0 */6 * * * cd /path/to/integration && ./synq-google-cloud-pubsub --relationships.enabled

​
Using as a Public API Example

This integration demonstrates best practices for using the SYNQ Public API:
  • OAuth2 authentication with client credentials
  • Creating and managing multiple custom entity types
  • Using entity groups for automatic cleanup
  • Managing relationships between entities
  • Implementing filtering and dry-run modes
  • Handling regional deployments
See the source code and API documentation for more details.

​
Troubleshooting

Verify your SYNQ credentials are correct in the .env file. Ensure you’re using the correct endpoint for your region (EU or US).
Set the GCP_PROJECT_ID environment variable explicitly or configure gcloud CLI with your project:
gcloud config set project YOUR_PROJECT
Ensure your GCP credentials have the following permissions:
  • pubsub.topics.list
  • pubsub.subscriptions.list
Use the default filter to exclude auto-generated per-pod subscriptions, or customize the filter patterns:
filter:
  subscriptions:
    exclude:
      - '-[a-z0-9]{9,10}-[a-z0-9]{5}\.subscription$'
      - 'test-.*'
If running behind a firewall, verify that outbound connections to the SYNQ API endpoint are allowed. Check your network configuration and firewall rules.

​
Support

For issues or questions: