Configuration & Usage

Detailed configuration, credential resolution order, caching, and runtime behavior for the bx-google-secrets module.

This guide covers effective settings, credential source precedence, local development, and operational behavior for bx-google-secrets.

🔧 Configuration Sources

Each setting is resolved independently in this order:

1. this.google in Application.bx (per-application)
2. Module settings in boxlang.json (global)
3. Google environment variables / Application Default Credentials

🧩 Application.bx (Per-App)

Use this.google when each app needs isolated project or credential behavior.

class {
    this.name = "myApp"

    this.google = {
        projectId       : "my-gcp-project",
        credentialsPath : "${GOOGLE_APPLICATION_CREDENTIALS}",
        credentialsJson : "",
        cacheTTL        : 300
    }
}

When this.google is present, the module creates and reuses a dedicated SecretManagerServiceClient for that application.

🌍 Global boxlang.json Settings

{
  "modules": {
    "bxgoogle-secrets": {
      "settings": {
        "projectId": "my-gcp-project",
        "credentialsPath": "${GOOGLE_APPLICATION_CREDENTIALS}",
        "credentialsJson": "",
        "cacheTTL": 300
      }
    }
  }
}

🌱 Environment Variable Fallback

Supported environment mappings:

Setting	Environment Variable(s)
projectId	GOOGLE_CLOUD_PROJECT, fallback GCLOUD_PROJECT
credentialsPath	GOOGLE_APPLICATION_CREDENTIALS
credentialsJson	GOOGLE_CREDENTIALS_JSON

If explicit credentials are not configured, the module can also rely on Google Application Default Credentials from environments such as Cloud Run, GKE, Compute Engine, App Engine, or a locally authenticated gcloud session.

📋 Settings Reference

Setting	Type	Default	Description
projectId	string	""	Google Cloud project ID required for secret resolution
credentialsPath	string	""	Optional service account JSON file path
credentialsJson	string	""	Optional raw service account JSON content
cacheTTL	numeric	300	Cache time-to-live in seconds

🔐 Usage Examples

Resolve a secret directly:

dbPassword = getSystemSetting( "google.DB_PASSWORD" )

Resolve with a fallback value:

apiToken = getSystemSetting( "google.API_TOKEN", "dev-token" )

Use in datasource config:

this.datasources = {
    main : {
        className : "org.postgresql.Driver",
        connectionString : "jdbc:postgresql://localhost:5432/app",
        username : "app_user",
        password : getSystemSetting( "google.DB_PASSWORD" )
    }
}

🧠 Caching Behavior

• Cache key format is projectId:secretName
• Successful secret fetches are cached in-memory
• Expired entries are refreshed on next access
• Set cacheTTL to 0 for effectively no cache reuse

🏗 Client Lifecycle

• Per-app client: Used when this.google exists
• Global client: Used when module settings provide project-based config
• ADC/env client: Used when relying only on environment credentials or Google Application Default Credentials

Per-app clients are closed on application shutdown, and all clients are closed on module/runtime shutdown.

🧪 Local Development with gcloud

Authenticate with Google Cloud CLI and set a project:

gcloud auth application-default login
export GOOGLE_CLOUD_PROJECT="my-gcp-project"
gcloud secrets create DB_PASSWORD --replication-policy="automatic"
gcloud secrets versions add DB_PASSWORD --data-file=- <<< "local-password"

Minimal module settings:

{
  "modules": {
    "bxgoogle-secrets": {
      "settings": {
        "projectId": "my-gcp-project"
      }
    }
  }
}

🚨 Troubleshooting

• Secret returns null: verify projectId is resolved and the secret exists in Google Secret Manager
• License errors: confirm bx-plus is installed and licensed; for local testing, set BX_GOOGLE_DEV=true
• Permission errors: ensure the runtime identity can access secret versions
• Wrong module settings key: use bxgoogle-secrets under modules in boxlang.json