Introduce git utilities in the API

packages/api/apps/app.mts

@@ -8,6 +8,7 @@ import { npmInstall } from '../exec.mjs';
 import { generateApp } from '../ai/generate.mjs';
 import { toValidPackageName } from '../apps/utils.mjs';
 import { getPackagesToInstall, parsePlan } from '../ai/plan-parser.mjs';
+import { commitAllFiles, initRepo } from './git.mjs';
 
 function toSecondsSinceEpoch(date: Date): number {
   return Math.floor(date.getTime() / 1000);
@@ -34,6 +35,9 @@ export async function createAppWithAi(data: CreateAppWithAiSchemaType): Promise<
   });
 
   await createViteApp(app);
+
+  await initRepo(app);
+
   // Note: we don't surface issues or retries and this is "running in the background".
   // In this case it works in our favor because we'll kickoff generation while it happens
   npmInstall({
@@ -69,6 +73,8 @@ export async function createAppWithAi(data: CreateAppWithAiSchemaType): Promise<
       },
       onExit(code) {
         console.log(`npm install exit code: ${code}`);
+        console.log('Applying git commit');
+        commitAllFiles(app, `Add dependencies: ${packagesToInstall.join(', ')}`);
       },
     });
   }

packages/api/apps/git.mts

@@ -0,0 +1,80 @@
+import fs from 'node:fs/promises';
+import Path from 'node:path';
+import git, { type ReadCommitResult } from 'isomorphic-git';
+import { pathToApp } from './disk.mjs';
+import type { App as DBAppType } from '../db/schema.mjs';
+
+// Initialize a git repository in the app directory
+export async function initRepo(app: DBAppType): Promise<void> {
+  const dir = pathToApp(app.externalId);
+  await git.init({ fs, dir });
+  await commitAllFiles(app, 'Initial commit');
+}
+
+// Commit all current files in the app directory
+export async function commitAllFiles(app: DBAppType, message: string): Promise<string> {
+  const dir = pathToApp(app.externalId);
+
+  // Stage all files
+  await git.add({ fs, dir, filepath: '.' });
+
+  // Create commit
+  const sha = await git.commit({
+    fs,
+    dir,
+    message,
+    author: {
+      name: 'Srcbook',
+      email: '[email protected]',
+    },
+  });
+
+  return sha;
+}
+
+// Checkout to a specific commit
+// Use this to revert to a previous commit or "version"
+export async function checkoutCommit(app: DBAppType, commitSha: string): Promise<void> {
+  const dir = pathToApp(app.externalId);
+
+  await git.checkout({
+    fs,
+    dir,
+    ref: commitSha,
+    force: true,
+  });
+}
+
+// Get commit history
+export async function getCommitHistory(
+  app: DBAppType,
+  limit: number = 100,
+): Promise<Array<ReadCommitResult>> {
+  const dir = pathToApp(app.externalId);
+
+  const commits = await git.log({
+    fs,
+    dir,
+    depth: limit, // Limit to specified number of commits, default 100
+  });
+
+  return commits;
+}
+
+// Helper function to ensure the repo exists, initializing it if necessary
+export async function ensureRepoExists(app: DBAppType): Promise<void> {
+  const dir = pathToApp(app.externalId);
+  try {
+    await fs.access(Path.join(dir, '.git'));
+  } catch (error) {
+    // If .git directory doesn't exist, initialize the repo
+    await initRepo(app);
+  }
+}
+
+// Get the current commit SHA
+export async function getCurrentCommitSha(app: DBAppType): Promise<string> {
+  const dir = pathToApp(app.externalId);
+  const currentCommit = await git.resolveRef({ fs, dir, ref: 'HEAD' });
+  return currentCommit;
+}

packages/api/apps/templates/react-typescript/.gitignore

@@ -0,0 +1,4 @@
+# typical gitignore for web apps
+node_modules
+dist
+.DS_Store

packages/api/package.json

@@ -33,6 +33,7 @@
     "drizzle-orm": "^0.33.0",
     "express": "^4.20.0",
     "fast-xml-parser": "^4.5.0",
+    "isomorphic-git": "^1.27.1",
     "marked": "catalog:",
     "posthog-node": "^4.2.0",
     "ws": "catalog:",

packages/api/server/http.mts

@@ -62,6 +62,7 @@ import {
 import { CreateAppSchema } from '../apps/schemas.mjs';
 import { AppGenerationFeedbackType } from '@srcbook/shared';
 import { createZipFromApp } from '../apps/disk.mjs';
+import { checkoutCommit, commitAllFiles, getCurrentCommitSha } from '../apps/git.mjs';
 
 const app: Application = express();
 
@@ -562,6 +563,44 @@ router.post('/apps/:id/edit', cors(), async (req, res) => {
   }
 });
 
+router.options('/apps/:id/commit', cors());
+router.get('/apps/:id/commit', cors(), async (req, res) => {
+  const { id } = req.params;
+  const app = await loadApp(id);
+  if (!app) {
+    return res.status(404).json({ error: 'App not found' });
+  }
+
+  const sha = await getCurrentCommitSha(app);
+  return res.json({ sha });
+});
+router.post('/apps/:id/commit', cors(), async (req, res) => {
+  const { id } = req.params;
+  const { message } = req.body;
+  // import the commit function from the apps/git.mjs file
+  const app = await loadApp(id);
+
+  if (!app) {
+    return res.status(404).json({ error: 'App not found' });
+  }
+
+  const sha = await commitAllFiles(app, message);
+  return res.json({ data: { success: true, sha } });
+});
+
+router.options('/apps/:id/checkout/:sha ', cors());
+router.post('/apps/:id/checkout/:sha', cors(), async (req, res) => {
+  const { id, sha } = req.params;
+  const app = await loadApp(id);
+
+  if (!app) {
+    return res.status(404).json({ error: 'App not found' });
+  }
+
+  await checkoutCommit(app, sha);
+  return res.json({ data: { success: true, sha } });
+});
+
 router.options('/apps/:id/directories', cors());
 router.post('/apps/:id/directories', cors(), async (req, res) => {
   const { id } = req.params;

packages/web/src/clients/http/apps.ts

@@ -295,3 +295,36 @@ export async function exportApp(id: string, name: string): Promise<Blob> {
 
   return response.blob();
 }
+
+type VersionResponse = {
+  sha: string;
+};
+
+export async function getCurrentVersion(id: string): Promise<VersionResponse> {
+  const response = await fetch(API_BASE_URL + `/apps/${id}/commit`, {
+    method: 'GET',
+    headers: { 'content-type': 'application/json' },
+  });
+  return response.json();
+}
+
+export async function commitVersion(id: string, message: string): Promise<VersionResponse> {
+  const response = await fetch(API_BASE_URL + `/apps/${id}/commit`, {
+    method: 'POST',
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify({ message }),
+  });
+
+  return response.json();
+}
+
+export async function checkoutVersion(
+  id: string,
+  sha: string,
+): Promise<{ data: { success: true; sha: string } }> {
+  const response = await fetch(API_BASE_URL + `/apps/${id}/checkout/${sha}`, {
+    method: 'POST',
+    headers: { 'content-type': 'application/json' },
+  });
+  return response.json();
+}

packages/web/src/components/apps/use-version.tsx

@@ -0,0 +1,89 @@
+import React, { createContext, useContext, useState, useCallback, useEffect } from 'react';
+import { useApp } from './use-app';
+import { commitVersion, getCurrentVersion } from '@/clients/http/apps';
+
+interface Version {
+  sha: string;
+  message?: string;
+}
+
+interface VersionContextType {
+  currentVersion: Version | null;
+  commitFiles: (message: string) => Promise<void>;
+  checkout: (sha: string) => Promise<void>;
+  fetchVersions: () => Promise<void>;
+}
+
+const VersionContext = createContext<VersionContextType | undefined>(undefined);
+
+export const VersionProvider: React.FC<{ children: React.ReactNode }> = ({ children }) => {
+  const { app } = useApp();
+  //   TODO implement this
+  //   const { refreshFiles } = useFiles();
+  const [currentVersion, setCurrentVersion] = useState<Version | null>(null);
+
+  const fetchVersion = useCallback(async () => {
+    if (!app) return;
+
+    try {
+      const currentVersionResponse = await getCurrentVersion(app.id);
+      setCurrentVersion({ sha: currentVersionResponse.sha });
+    } catch (error) {
+      console.error('Error fetching current version:', error);
+    }
+  }, [app]);
+
+  useEffect(() => {
+    fetchVersion();
+  }, [fetchVersion]);
+
+  const commitFiles = useCallback(
+    async (message: string) => {
+      if (!app) return;
+
+      try {
+        const response = await commitVersion(app.id, message);
+        setCurrentVersion({ sha: response.sha, message });
+      } catch (error) {
+        console.error('Error committing files:', error);
+      }
+    },
+    [app],
+  );
+
+  const checkout = useCallback(
+    async (sha: string) => {
+      if (!app) return;
+
+      try {
+        const response = await fetch(`/api/apps/${app.id}/checkout`, {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({ sha }),
+        });
+        if (!response.ok) throw new Error('Failed to checkout version');
+        await fetchVersion();
+        // await refreshFiles();
+      } catch (error) {
+        console.error('Error checking out version:', error);
+      }
+    },
+    [app, fetchVersion],
+  );
+
+  return (
+    <VersionContext.Provider
+      value={{ currentVersion, commitFiles, checkout, fetchVersions: fetchVersion }}
+    >
+      {children}
+    </VersionContext.Provider>
+  );
+};
+
+export const useVersion = () => {
+  const context = useContext(VersionContext);
+  if (context === undefined) {
+    throw new Error('useVersion must be used within a VersionProvider');
+  }
+  return context;
+};

packages/web/src/components/chat.tsx

@@ -47,6 +47,7 @@ import { DiffStats } from './apps/diff-stats.js';
 import { useApp } from './apps/use-app.js';
 import { usePackageJson } from './apps/use-package-json.js';
 import { AiFeedbackModal } from './apps/AiFeedbackModal';
+import { useVersion } from './apps/use-version.js';
 
 function Chat({
   history,
@@ -264,6 +265,7 @@ function DiffBox({
   version: number;
   planId: string;
 }) {
+  const { currentVersion } = useVersion();
   const [showFeedbackToast, setShowFeedbackToast] = React.useState(false);
   const [feedbackGiven, _setFeedbackGiven] = React.useState<null | 'positive' | 'negative'>(null);
   const [isFeedbackModalOpen, setIsFeedbackModalOpen] = React.useState(false);
@@ -286,6 +288,11 @@ function DiffBox({
           <div className="flex gap-2 items-center text-sm h-10">
             <span className="font-medium">{app.name}</span>
             <span className="font-mono px-1 bg-ai-border rounded-sm">v{version}</span>
+            {currentVersion && (
+              <span className="font-mono px-1 bg-ai-border rounded-sm">
+                {currentVersion.sha.slice(0, 7)}
+              </span>
+            )}
           </div>
           <div>
             {files.map((file) => (

packages/web/src/routes/apps/context.tsx

@@ -6,6 +6,7 @@ import { PreviewProvider } from '@/components/apps/use-preview';
 import { LogsProvider } from '@/components/apps/use-logs';
 import { PackageJsonProvider } from '@/components/apps/use-package-json';
 import { AppProvider, useApp } from '@/components/apps/use-app';
+import { VersionProvider } from '@/components/apps/use-version';
 
 export function AppContext() {
   const { app } = useLoaderData() as { app: AppType };
@@ -34,9 +35,11 @@ export function AppProviders(props: { children: React.ReactNode }) {
       initialOpenedFile={initialOpenedFile}
     >
       <LogsProvider channel={channel}>
-        <PackageJsonProvider channel={channel}>
-          <PreviewProvider channel={channel}>{props.children}</PreviewProvider>
-        </PackageJsonProvider>
+        <VersionProvider>
+          <PackageJsonProvider channel={channel}>
+            <PreviewProvider channel={channel}>{props.children}</PreviewProvider>
+          </PackageJsonProvider>
+        </VersionProvider>
       </LogsProvider>
     </FilesProvider>
   );