From fd7a5747c7faab218eb047c9c7140da8e8f165fa Mon Sep 17 00:00:00 2001
From: Andrey Avtomonov <andreybavt@gmail.com>
Date: Sun, 17 May 2026 19:01:11 +0200
Subject: [PATCH] test: validate metabase source mapping requirements

---
 packages/cli/src/source-mapping.test.ts | 85 +++++++++++++++++++++++++
 packages/cli/src/source-mapping.ts      |  9 +++
 2 files changed, 94 insertions(+)
 create mode 100644 packages/cli/src/source-mapping.test.ts

diff --git a/packages/cli/src/source-mapping.test.ts b/packages/cli/src/source-mapping.test.ts
new file mode 100644
index 00000000..83f9496b
--- /dev/null
+++ b/packages/cli/src/source-mapping.test.ts
@@ -0,0 +1,85 @@
+import { mkdtemp, rm, writeFile } from 'node:fs/promises';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import type { KtxCliIo } from './cli-runtime.js';
+import { runKtxSourceMapping } from './source-mapping.js';
+
+function makeIo() {
+  let stdout = '';
+  let stderr = '';
+  return {
+    io: {
+      stdout: {
+        write: (chunk: string) => {
+          stdout += chunk;
+        },
+      },
+      stderr: {
+        write: (chunk: string) => {
+          stderr += chunk;
+        },
+      },
+    } satisfies KtxCliIo,
+    stdout: () => stdout,
+    stderr: () => stderr,
+  };
+}
+
+describe('source mapping commands', () => {
+  let tempDir: string;
+
+  beforeEach(async () => {
+    tempDir = await mkdtemp(join(tmpdir(), 'ktx-source-mapping-'));
+  });
+
+  afterEach(async () => {
+    await rm(tempDir, { recursive: true, force: true });
+  });
+
+  async function writeConfig(metabaseMappings: string[]): Promise<void> {
+    await writeFile(
+      join(tempDir, 'ktx.yaml'),
+      [
+        'connections:',
+        '  warehouse:',
+        '    driver: postgres',
+        '    url: env:DATABASE_URL',
+        '  metabase:',
+        '    driver: metabase',
+        '    api_url: https://metabase.example.com',
+        ...metabaseMappings,
+        '',
+      ].join('\n'),
+      'utf-8',
+    );
+  }
+
+  it('fails Metabase validation when no sync-enabled target mapping exists', async () => {
+    await writeConfig([]);
+    const io = makeIo();
+
+    await expect(
+      runKtxSourceMapping({ command: 'validate', projectDir: tempDir, connectionId: 'metabase' }, io.io),
+    ).resolves.toBe(1);
+
+    expect(io.stderr()).toContain('no sync-enabled mappings with a target connection for Metabase connection metabase');
+  });
+
+  it('passes Metabase validation when a sync-enabled target mapping exists', async () => {
+    await writeConfig([
+      '    mappings:',
+      '      databaseMappings:',
+      '        "3": warehouse',
+      '      syncEnabled:',
+      '        "3": true',
+    ]);
+    const io = makeIo();
+
+    await expect(
+      runKtxSourceMapping({ command: 'validate', projectDir: tempDir, connectionId: 'metabase' }, io.io),
+    ).resolves.toBe(0);
+
+    expect(io.stdout()).toContain('Mapping validation passed: metabase');
+  });
+});
diff --git a/packages/cli/src/source-mapping.ts b/packages/cli/src/source-mapping.ts
index 3f8e8782..13fa15fb 100644
--- a/packages/cli/src/source-mapping.ts
+++ b/packages/cli/src/source-mapping.ts
@@ -12,6 +12,7 @@ import {
   discoverMetabaseDatabases,
   lookerCredentialsFromLocalConnection,
   metabaseRuntimeConfigFromLocalConnection,
+  planMetabaseFanoutChildren,
   seedLocalMappingStateFromKtxYaml,
   validateLookerMappings,
   validateMappingPhysicalMatch,
@@ -198,6 +199,14 @@ export async function runKtxSourceMapping(
     }
 
     const rows = await store.listDatabaseMappings(args.connectionId);
+    planMetabaseFanoutChildren({
+      metabaseConnectionId: args.connectionId,
+      mappings: rows.map((row) => ({
+        metabaseDatabaseId: row.metabaseDatabaseId,
+        targetConnectionId: row.targetConnectionId,
+        syncEnabled: row.syncEnabled,
+      })),
+    });
     const failures = rows.flatMap((row) => {
       if (!row.targetConnectionId) {
         return [];