Function main

src/server.ts:55–338

()

 * Initialize and start the DBHub server
 */
export async function main(): Promise<void> {
  try {
    // Resolve source configurations from TOML or fallback to single DSN
    const sourceConfigsData = await resolveSourceConfigs();

    if (!sourceConfigsData) {
      const samples = ConnectorRegistry.getAllSampleDSNs();
      const sampleFormats = Object.entries(samples)
        .map(([id, dsn]) => `  - ${id}: ${dsn}`)
        .join("\n");

      console.error(`
ERROR: Database connection configuration is required.
Please provide configuration in one of these ways (in order of priority):

1. Use demo mode: --demo (uses in-memory SQLite with sample employee database)
2. TOML config file: --config=path/to/dbhub.toml or ./dbhub.toml
3. Command line argument: --dsn="your-connection-string"
4. Environment variable: export DSN="your-connection-string"
5. .env file: DSN=your-connection-string

Example DSN formats:
${sampleFormats}

Example TOML config (dbhub.toml):
  [[sources]]
  id = "my_db"
  dsn = "postgres://user:pass@localhost:5432/dbname"

See documentation for more details on configuring database connections.
`);
      process.exit(1);
    }

    // Create connector manager and connect to database(s)
    const connectorManager = new ConnectorManager();
    const sources = sourceConfigsData.sources;

    console.error(`Configuration source: ${sourceConfigsData.source}`);

    // Connect to database(s) - works uniformly for all modes (demo, single DSN, multi-source TOML)
    await connectorManager.connectWithSources(sources);

    // Initialize tool registry (manages both built-in and custom tools)
    // This must happen AFTER ConnectorManager is initialized so source validation works
    const { initializeToolRegistry } = await import("./tools/registry.js");
    initializeToolRegistry({
      sources: sourceConfigsData.sources,
      tools: sourceConfigsData.tools,
    });
    console.error("Tool registry initialized");

    // Start watching TOML config file for hot reload (only when using TOML config).
    // In STDIO mode, tool list is registered once — hot reload updates connections and
    // tool registry, but STDIO clients won't see added/removed tools without restart.
    // HTTP transport creates a new server per request, so tool changes apply immediately.
    const stopConfigWatcher = startConfigWatcher({
      connectorManager,