feat(gateway,storage): mosaic gateway doctor with tier health JSON (FED-M1-06) (#475)

packages/mosaic/src/commands/gateway-doctor.ts

@@ -0,0 +1,143 @@
+/**
+ * gateway-doctor.ts — `mosaic gateway doctor` implementation.
+ *
+ * Reports current tier and per-service health (PG, Valkey, pgvector) for the
+ * Mosaic gateway. Supports machine-readable JSON output for CI.
+ *
+ * Exit codes:
+ *   0 — overall green or yellow
+ *   1 — overall red (at least one required service failed)
+ */
+
+import { existsSync } from 'node:fs';
+import { resolve, join } from 'node:path';
+import { homedir } from 'node:os';
+import { loadConfig } from '@mosaicstack/config';
+import { probeServiceHealth } from '@mosaicstack/storage';
+import type { TierHealthReport, ServiceCheck } from '@mosaicstack/storage';
+
+/* ------------------------------------------------------------------ */
+/*  Config resolution                                                   */
+/* ------------------------------------------------------------------ */
+
+const CONFIG_CANDIDATES = [
+  resolve(process.cwd(), 'mosaic.config.json'),
+  join(homedir(), '.mosaic', 'mosaic.config.json'),
+];
+
+/**
+ * Resolve the config path to report in output.
+ *
+ * Priority:
+ *   1. Explicit `--config <path>` flag
+ *   2. `./mosaic.config.json` (cwd)
+ *   3. `~/.mosaic/mosaic.config.json`
+ *   4. undefined — `loadConfig()` falls back to env-var detection
+ *
+ * `loadConfig()` itself already handles priority 1-3 when passed an explicit
+ * path, and falls back to env-detection when none exists.  We resolve here
+ * only so we can surface the path in the health report.
+ */
+function resolveConfigPath(explicit?: string): string | undefined {
+  if (explicit) return resolve(explicit);
+  for (const candidate of CONFIG_CANDIDATES) {
+    if (existsSync(candidate)) return candidate;
+  }
+  return undefined;
+}
+
+/* ------------------------------------------------------------------ */
+/*  Output helpers                                                      */
+/* ------------------------------------------------------------------ */
+
+const TICK = '\u2713'; // ✓
+const CROSS = '\u2717'; // ✗
+const SKIP = '-';
+
+function padRight(s: string, n: number): string {
+  return s + ' '.repeat(Math.max(0, n - s.length));
+}
+
+function serviceLabel(svc: ServiceCheck): string {
+  const hostPort =
+    svc.host !== undefined && svc.port !== undefined ? `${svc.host}:${svc.port.toString()}` : '';
+  const duration = `(${svc.durationMs.toString()}ms)`;
+
+  switch (svc.status) {
+    case 'ok':
+      return `  ${TICK} ${padRight(svc.name, 10)} ${padRight(hostPort, 22)} ${duration}`;
+    case 'fail': {
+      const errMsg = svc.error?.message ?? 'unknown error';
+      return `  ${CROSS} ${padRight(svc.name, 10)} ${padRight(hostPort, 22)} ${duration}  \u2192 ${errMsg}`;
+    }
+    case 'skipped':
+      return `  ${SKIP} ${padRight(svc.name, 10)} (skipped)`;
+  }
+}
+
+function printReport(report: TierHealthReport): void {
+  const configDisplay = report.configPath ?? '(auto-detected)';
+  console.log(`Tier: ${report.tier}  Config: ${configDisplay}`);
+  console.log('');
+
+  for (const svc of report.services) {
+    console.log(serviceLabel(svc));
+  }
+
+  console.log('');
+
+  // Print remediations for failed services.
+  const failed = report.services.filter((s) => s.status === 'fail' && s.error);
+  if (failed.length > 0) {
+    console.log('Remediations:');
+    for (const svc of failed) {
+      if (svc.error) {
+        console.log(`  ${svc.name}: ${svc.error.remediation}`);
+      }
+    }
+    console.log('');
+  }
+
+  console.log(`Overall: ${report.overall.toUpperCase()}`);
+}
+
+/* ------------------------------------------------------------------ */
+/*  Main runner                                                         */
+/* ------------------------------------------------------------------ */
+
+export interface GatewayDoctorOptions {
+  json?: boolean;
+  config?: string;
+}
+
+export async function runGatewayDoctor(opts: GatewayDoctorOptions): Promise<void> {
+  const configPath = resolveConfigPath(opts.config);
+
+  let mosaicConfig;
+  try {
+    mosaicConfig = loadConfig(configPath);
+  } catch (err) {
+    const msg = err instanceof Error ? err.message : String(err);
+    if (opts.json) {
+      process.stdout.write(
+        JSON.stringify({ error: `Failed to load config: ${msg}` }, null, 2) + '\n',
+      );
+    } else {
+      process.stderr.write(`Error: Failed to load config: ${msg}\n`);
+    }
+    process.exit(1);
+  }
+
+  const report = await probeServiceHealth(mosaicConfig, configPath);
+
+  if (opts.json) {
+    process.stdout.write(JSON.stringify(report, null, 2) + '\n');
+  } else {
+    printReport(report);
+  }
+
+  // Exit 1 if overall is red.
+  if (report.overall === 'red') {
+    process.exit(1);
+  }
+}