Implementations Of The Deployment Database Introspection Logic

[abdotop]

feat(schema): add endpoint to fetch cached database schema and implement schema refresh loop

[Copilot]

Pull Request Overview

This PR adds database schema introspection functionality to the deployment system. It implements automatic detection of database dialects, schema retrieval, and a periodic refresh mechanism to keep schema information current.

Key changes:

• Adds comprehensive SQL dialect detection and schema introspection for multiple database types (PostgreSQL, MySQL, SQLite, SQL Server, Oracle, DuckDB)
• Implements a periodic background schema refresh loop that updates cached database schemas
• Provides a new API endpoint to fetch cached database schema information for deployments

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
api/sql.ts	Core implementation of database dialect detection, schema introspection queries, and refresh logic
api/server.ts	Integration of schema refresh loop startup in the main server initialization
api/schema.ts	Database schema model definition and collection setup for caching schema data
api/routes.ts	New API endpoint to retrieve cached database schema for a deployment

Comments suppressed due to low confidence (1)

api/sql.ts:1

• The Oracle query has incorrect SQL syntax. The assignment table_schema = owner AS table_schema is invalid. It should be owner AS table_schema.

import { DatabaseSchemasCollection, DeploymentsCollection } from './schema.ts'

---

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[Copilot]

The initial schema refresh call is not awaited, which means the interval starts immediately without waiting for the first refresh to complete. This could lead to overlapping refresh operations if the refresh takes longer than the interval. Consider awaiting this call or adding concurrency protection.

Suggested change

	export function startSchemaRefreshLoop() {
	if (intervalHandle) return
	// initial kick (non-blocking)
	refreshAllSchemas()
	export async function startSchemaRefreshLoop() {
	if (intervalHandle) return
	// initial kick (awaited)
	await refreshAllSchemas()

[Copilot]

Sequential processing of deployments could be slow with many deployments. Consider using Promise.allSettled() to refresh schemas concurrently while preventing one failure from blocking others.

Suggested change

	for (const dep of DeploymentsCollection.values()) {
	await refreshOneSchema(dep)
	}
	await Promise.allSettled(
	Array.from(DeploymentsCollection.values()).map(dep => refreshOneSchema(dep))
	);

[Copilot]

The output schema definition duplicates the DatabaseSchemaDef from schema.ts. Consider importing and reusing DatabaseSchemaDef to maintain consistency and reduce duplication.