fix: merge provider base URL config from DB (#1676)

Co-authored-by: The Lord Argus <215461619+TheLordArgus@users.noreply.github.com>

src/core/config.ts

@@ -620,7 +620,10 @@ export function loadConfig(): GBrainConfig | null {
  * size the schema and must be stable across engine connect.
  */
 export async function loadConfigWithEngine(
-  engine: { getConfig(key: string): Promise<string | null | undefined> },
+  engine: {
+    getConfig(key: string): Promise<string | null | undefined>;
+    listConfigKeys?(prefix: string): Promise<string[]>;
+  },
   base?: GBrainConfig | null,
 ): Promise<GBrainConfig | null> {
   // Codex /ship finding #3: when there's no file config AND no env DB URL,
@@ -657,11 +660,31 @@ export async function loadConfigWithEngine(
       return undefined;
     }
   }
+  async function dbPrefixMap(prefix: string): Promise<Record<string, string> | undefined> {
+    if (typeof engine.listConfigKeys !== 'function') return undefined;
+    let keys: string[];
+    try {
+      keys = await engine.listConfigKeys(prefix);
+    } catch {
+      return undefined;
+    }
+
+    const out: Record<string, string> = {};
+    for (const key of keys.sort()) {
+      if (!key.startsWith(prefix)) continue;
+      const leaf = key.slice(prefix.length);
+      if (!leaf) continue;
+      const value = await dbStr(key);
+      if (value !== undefined) out[leaf] = value;
+    }
+    return Object.keys(out).length > 0 ? out : undefined;
+  }
 
   const dbMultimodal = await dbBool('embedding_multimodal');
   const dbMultimodalModel = await dbStr('embedding_multimodal_model');
   const dbOcr = await dbBool('embedding_image_ocr');
   const dbOcrModel = await dbStr('embedding_image_ocr_model');
+  const dbProviderBaseUrls = await dbPrefixMap('provider_base_urls.');
   // v0.36 (D7) — embedding-column registry merge. Stored as JSON string in
   // the config table. Parse + shape-check here; full registry validation
   // (regex on keys, type/dim/provider field shapes) runs in the resolver at
@@ -685,6 +708,15 @@ export async function loadConfigWithEngine(
   if (merged.embedding_image_ocr_model === undefined && dbOcrModel !== undefined) {
     merged.embedding_image_ocr_model = dbOcrModel;
   }
+  if (dbProviderBaseUrls !== undefined) {
+    const next = { ...(merged.provider_base_urls ?? {}) };
+    for (const [providerId, baseUrl] of Object.entries(dbProviderBaseUrls)) {
+      if (next[providerId] === undefined) next[providerId] = baseUrl;
+    }
+    if (Object.keys(next).length > 0) {
+      merged.provider_base_urls = next;
+    }
+  }
   if (merged.embedding_columns === undefined && dbEmbeddingColumns !== undefined) {
     try {
       const parsed = JSON.parse(dbEmbeddingColumns);

test/cli-multimodal-integration.test.ts

@@ -8,13 +8,15 @@
 //
 // PGLite-only: in-memory engine, no DATABASE_URL needed.
 
-import { afterAll, beforeAll, beforeEach, describe, expect, test } from 'bun:test';
+import { afterAll, afterEach, beforeAll, beforeEach, describe, expect, test } from 'bun:test';
 import { PGLiteEngine } from '../src/core/pglite-engine.ts';
 import { loadConfigWithEngine, type GBrainConfig } from '../src/core/config.ts';
 import {
+  __setRerankTransportForTests,
   configureGateway,
   getEmbeddingModel,
   getMultimodalModel,
+  rerank,
   resetGateway,
 } from '../src/core/ai/gateway.ts';
 import type { AIGatewayConfig } from '../src/core/ai/types.ts';
@@ -52,10 +54,16 @@ afterAll(async () => {
 
 beforeEach(async () => {
   resetGateway();
+  __setRerankTransportForTests(null);
   // Clear any prior config rows so tests are independent. setConfig with
   // empty string is treated as undefined by loadConfigWithEngine (per
   // dbStr semantics), so this is safe to call between tests.
   await engine.setConfig('embedding_multimodal_model', '');
+  await engine.setConfig('provider_base_urls.llama-server-reranker', '');
+});
+
+afterEach(() => {
+  __setRerankTransportForTests(null);
 });
 
 describe('cli connectEngine — embedding_multimodal_model DB→gateway plumbing', () => {
@@ -122,4 +130,34 @@ describe('cli connectEngine — embedding_multimodal_model DB→gateway plumbing
     expect(getEmbeddingModel()).toBe('openai:text-embedding-3-large');
     expect(getMultimodalModel()).toBeUndefined();
   });
+
+  test('DB-set provider_base_urls.llama-server-reranker flows to gateway.rerank URL', async () => {
+    await engine.setConfig('provider_base_urls.llama-server-reranker', 'http://127.0.0.1:8091/v1');
+
+    const baseConfig: GBrainConfig = {
+      engine: 'pglite',
+      embedding_model: 'openai:text-embedding-3-large',
+      embedding_dimensions: 1536,
+    };
+
+    const merged = await loadConfigWithEngine(engine, baseConfig);
+    configureGateway(buildGatewayConfig(merged!));
+
+    let capturedUrl = '';
+    __setRerankTransportForTests(async (url) => {
+      capturedUrl = url;
+      return new Response(JSON.stringify({ results: [{ index: 0, relevance_score: 0.9 }] }), {
+        status: 200,
+        headers: { 'content-type': 'application/json' },
+      });
+    });
+
+    await rerank({
+      query: 'q',
+      documents: ['d'],
+      model: 'llama-server-reranker:qwen3-reranker-4b',
+    });
+
+    expect(capturedUrl).toBe('http://127.0.0.1:8091/v1/rerank');
+  });
 });

test/loadConfig-merge.test.ts

@@ -9,6 +9,7 @@ import { loadConfigWithEngine, type GBrainConfig } from '../src/core/config.ts';
 
 interface FakeEngine {
   getConfig(key: string): Promise<string | null | undefined>;
+  listConfigKeys?(prefix: string): Promise<string[]>;
 }
 
 function makeEngine(map: Record<string, string | null | undefined>): FakeEngine {
@@ -16,6 +17,9 @@ function makeEngine(map: Record<string, string | null | undefined>): FakeEngine
     async getConfig(key: string) {
       return map[key];
     },
+    async listConfigKeys(prefix: string) {
+      return Object.keys(map).filter(key => key.startsWith(prefix));
+    },
   };
 }
 
@@ -92,6 +96,31 @@ describe('loadConfigWithEngine (Phase 4 / F3)', () => {
     expect(merged?.embedding_image_ocr).toBe(true);
   });
 
+  test('DB provider_base_urls.<provider> fills the gateway base URL map', async () => {
+    const base: GBrainConfig = { engine: 'pglite' };
+    const engine = makeEngine({
+      'provider_base_urls.llama-server-reranker': 'http://127.0.0.1:8091/v1',
+    });
+    const merged = await loadConfigWithEngine(engine, base);
+    expect(merged?.provider_base_urls?.['llama-server-reranker']).toBe('http://127.0.0.1:8091/v1');
+  });
+
+  test('provider_base_urls merge is per-provider: file value wins and DB fills siblings', async () => {
+    const base: GBrainConfig = {
+      engine: 'pglite',
+      provider_base_urls: {
+        'llama-server-reranker': 'http://file.example/v1',
+      },
+    };
+    const engine = makeEngine({
+      'provider_base_urls.llama-server-reranker': 'http://db.example/v1',
+      'provider_base_urls.openrouter': 'http://openrouter.example/v1',
+    });
+    const merged = await loadConfigWithEngine(engine, base);
+    expect(merged?.provider_base_urls?.['llama-server-reranker']).toBe('http://file.example/v1');
+    expect(merged?.provider_base_urls?.openrouter).toBe('http://openrouter.example/v1');
+  });
+
   test('engine.getConfig throwing is non-fatal — file/env config still returned', async () => {
     const base: GBrainConfig = {
       engine: 'pglite',