Fix health DB connectivity probe

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/__tests__/health.test.ts

@@ -1,16 +1,56 @@
-import { describe, it, expect } from "vitest";
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
 import express from "express";
 import request from "supertest";
+import type { Db } from "@paperclipai/db";
 import { healthRoutes } from "../routes/health.js";
+import * as devServerStatus from "../dev-server-status.js";
 import { serverVersion } from "../version.js";
 
 describe("GET /health", () => {
-  const app = express();
-  app.use("/health", healthRoutes());
+  beforeEach(() => {
+    vi.spyOn(devServerStatus, "readPersistedDevServerStatus").mockReturnValue(undefined);
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
 
   it("returns 200 with status ok", async () => {
+    const app = express();
+    app.use("/health", healthRoutes());
+
     const res = await request(app).get("/health");
     expect(res.status).toBe(200);
     expect(res.body).toEqual({ status: "ok", version: serverVersion });
   });
+
+  it("returns 200 when the database probe succeeds", async () => {
+    const db = {
+      execute: vi.fn().mockResolvedValue([{ "?column?": 1 }]),
+    } as unknown as Db;
+    const app = express();
+    app.use("/health", healthRoutes(db));
+
+    const res = await request(app).get("/health");
+
+    expect(res.status).toBe(200);
+    expect(res.body).toMatchObject({ status: "ok", version: serverVersion });
+  });
+
+  it("returns 503 when the database probe fails", async () => {
+    const db = {
+      execute: vi.fn().mockRejectedValue(new Error("connect ECONNREFUSED")),
+    } as unknown as Db;
+    const app = express();
+    app.use("/health", healthRoutes(db));
+
+    const res = await request(app).get("/health");
+
+    expect(res.status).toBe(503);
+    expect(res.body).toEqual({
+      status: "unhealthy",
+      version: serverVersion,
+      error: "database_unreachable",
+    });
+  });
 });

server/src/routes/health.ts

@@ -29,6 +29,17 @@ export function healthRoutes(
       return;
     }
 
+    try {
+      await db.execute(sql`SELECT 1`);
+    } catch {
+      res.status(503).json({
+        status: "unhealthy",
+        version: serverVersion,
+        error: "database_unreachable",
+      });
+      return;
+    }
+
     let bootstrapStatus: "ready" | "bootstrap_pending" = "ready";
     let bootstrapInviteActive = false;
     if (opts.deploymentMode === "authenticated") {