scadalink-design/docs/plans/2026-03-17-deploy-artifacts-remove-configdb-design.md

Design: Deploy Artifacts to Sites — Remove Config DB Dependency

Date: 2026-03-17 Status: Approved

Problem

ExternalSystemClient, DatabaseGateway, and NotificationDeliveryService query the central config DB at runtime from site servers. The data is already deployed to local SQLite via DeployArtifactsCommand but never read back. Sites should be fully self-contained after artifact deployment.

Changes

1. Site-local repository implementations

Create SiteExternalSystemRepository and SiteNotificationRepository that read from SiteStorageService (SQLite) instead of EF Core config DB repositories. Implement IExternalSystemRepository and INotificationRepository interfaces backed by SQLite queries.

2. Remove AddConfigurationDatabase from Site role

Replace AddConfigurationDatabase in Program.cs Site role with site-local repository registrations. Site no longer needs a SQL Server connection string.

3. Add "Deploy Artifacts" button to Admin UI

On the Sites page, add a "Deploy Artifacts" button per site that:

• Collects all external systems, database connections, notification lists + recipients, SMTP configs from config DB
• Sends DeployArtifactsCommand to the site via CommunicationService
• Shows success/failure toast

4. Include data connections in artifact deployment

Extend DeployArtifactsCommand to include data connection definitions (OPC UA endpoints, etc). Add StoreDataConnectionDefinitionAsync to SiteStorageService.

5. No change to FlattenedConfiguration

The DCL already reads connection config from FlattenedConfiguration.Connections dict, populated during flattening from config DB. This stays as-is.

Outcome

After artifact deployment, sites operate without any config DB access. The config DB connection string is removed from appsettings.Site.json.