Hi

\"\n});\n```\n\n## Val Town Utility Functions\n\nVal Town provides several utility functions to help with common project tasks.\n\n### Importing Utilities\n\nAlways import utilities with version pins to avoid breaking changes:\n\n```ts\nimport { parseProject, readFile, serveFile } from \"https://esm.town/v/std/utils@85-main/index.ts\";\n```\n\n### Available Utilities\n\n\n#### **serveFile** - Serve project files with proper content types\n\nFor example, in Hono:\n\n```ts\n// serve all files in frontend/ and shared/\napp.get(\"/frontend/*\", c => serveFile(c.req.path, import.meta.url));\napp.get(\"/shared/*\", c => serveFile(c.req.path, import.meta.url));\n```\n\n#### **readFile** - Read files from within the project:\n\n```ts\n// Read a file from the project\nconst fileContent = await readFile(\"/frontend/index.html\", import.meta.url);\n```\n\n#### **listFiles** - List all files in the project\n\n```ts\nconst files = await listFiles(import.meta.url);\n```\n\n#### **parseProject** - Extract information about the current project from import.meta.url\n\nThis is useful for including info for linking back to a val, ie in \"view source\" urls:\n\n```ts\nconst projectVal = parseProject(import.meta.url);\nconsole.log(projectVal.username); // Owner of the project\nconsole.log(projectVal.name); // Project name\nconsole.log(projectVal.version); // Version number\nconsole.log(projectVal.branch); // Branch name\nconsole.log(projectVal.links.self.project); // URL to the project page\n```\n\nHowever, it's *extremely importing* to note that `parseProject` and other Standard Library utilities ONLY RUN ON THE SERVER.\nIf you need access to this data on the client, run it in the server and pass it to the client by splicing it into the HTML page\nor by making an API request for it.\n\n## Val Town Platform Specifics\n\n- **Redirects:** Use `return new Response(null, { status: 302, headers: { Location: \"/place/to/redirect\" }})` instead of `Response.redirect` which is broken\n- **Images:** Avoid external images or base64 images. Use emojis, unicode symbols, or icon fonts/libraries instead\n- **AI Image:** To inline generate an AI image use: `

`\n- **Storage:** DO NOT use the Deno KV module for storage\n- **Browser APIs:** DO NOT use the `alert()`, `prompt()`, or `confirm()` methods\n- **Weather Data:** Use open-meteo for weather data (doesn't require API keys) unless otherwise specified\n- **View Source:** Add a view source link by importing & using `import.meta.url.replace(\"ems.sh\", \"val.town)\"` (or passing this data to the client) and include `target=\"_top\"` attribute\n- **Error Debugging:** Add `` to HTML to capture client-side errors\n- **Error Handling:** Only use try...catch when there's a clear local resolution; Avoid catches that merely log or return 500s. Let errors bubble up with full context\n- **Environment Variables:** Use `Deno.env.get('keyname')` when you need to, but generally prefer APIs that don't require keys\n- **Imports:** Use `https://esm.sh` for npm and Deno dependencies to ensure compatibility on server and browser\n- **Storage Strategy:** Only use backend storage if explicitly required; prefer simple static client-side sites\n- **React Configuration:** When using React libraries, pin versions with `?deps=react@18.2.0,react-dom@18.2.0` and start the file with `/** @jsxImportSource https://esm.sh/react@18.2.0 */`\n- Ensure all React dependencies and sub-dependencies are pinned to the same version\n- **Styling:** Default to using TailwindCSS via `` unless otherwise specified\n\n## Project Structure and Design Patterns\n\n### Recommended Directory Structure\n```\n├── backend/\n│ ├── database/\n│ │ ├── migrations.ts # Schema definitions\n│ │ ├── queries.ts # DB query functions\n│ │ └── README.md\n│ └── routes/ # Route modules\n│ ├── [route].ts\n│ └── static.ts # Static file serving\n│ ├── index.ts # Main entry point\n│ └── README.md\n├── frontend/\n│ ├── components/\n│ │ ├── App.tsx\n│ │ └── [Component].tsx\n│ ├── favicon.svg\n│ ├── index.html # Main HTML template\n│ ├── index.tsx # Frontend JS entry point\n│ ├── README.md\n│ └── style.css\n├── README.md\n└── shared/\n ├── README.md\n └── utils.ts # Shared types and functions\n```\n\n### Backend (Hono) Best Practices\n\n- Hono is the recommended API framework\n- Main entry point should be `backend/index.ts`\n- **Static asset serving:** Use the utility functions to read and serve project files:\n ```ts\n import { readFile, serveFile } from \"https://esm.town/v/std/utils@85-main/index.ts\";\n \n // serve all files in frontend/ and shared/\n app.get(\"/frontend/*\", c => serveFile(c.req.path, import.meta.url));\n app.get(\"/shared/*\", c => serveFile(c.req.path, import.meta.url));\n \n // For index.html, often you'll want to bootstrap with initial data\n app.get(\"/\", async c => {\n let html = await readFile(\"/frontend/index.html\", import.meta.url);\n \n // Inject data to avoid extra round-trips\n const initialData = await fetchInitialData();\n const dataScript = ``;\n \n html = html.replace(\"\", `${dataScript}`);\n return c.html(html);\n });\n ```\n- Create RESTful API routes for CRUD operations\n- Always include this snippet at the top-level Hono app to re-throwing errors to see full stack traces:\n ```ts\n // Unwrap Hono errors to see original error details\n app.onError((err, c) => {\n throw err;\n });\n ```\n\n### Database Patterns\n- Run migrations on startup or comment out for performance\n- Change table names when modifying schemas rather than altering\n- Export clear query functions with proper TypeScript typing\n\n## Common Gotchas and Solutions\n\n1. **Environment Limitations:** \n - Val Town runs on Deno in a serverless context, not Node.js\n - Code in `shared/` must work in both frontend and backend environments\n - Cannot use `Deno` keyword in shared code\n - Use `https://esm.sh` for imports that work in both environments\n\n2. **SQLite Peculiarities:**\n - Limited support for ALTER TABLE operations\n - Create new tables with updated schemas and copy data when needed\n - Always run table creation before querying\n\n3. **React Configuration:**\n - All React dependencies must be pinned to 18.2.0\n - Always include `@jsxImportSource https://esm.sh/react@18.2.0` at the top of React files\n - Rendering issues often come from mismatched React versions\n\n4. **File Handling:**\n - Val Town only supports text files, not binary\n - Use the provided utilities to read files across branches and forks\n - For files in the project, use `readFile` helpers\n\n5. **API Design:**\n - `fetch` handler is the entry point for HTTP vals\n - Run the Hono app with `export default app.fetch // This is the entry point for HTTP vals`\n\n",[],[191],{"_106":199,"_97":200,"_163":201,"_165":-5,"_166":148,"_167":202,"_168":22,"_108":203,"_102":33,"_171":204,"_173":205,"_174":22,"_175":-5,"_176":206,"_100":207},"b8ff5894-0c42-11f1-b2fa-42dde27851f2","books.ts","b8ff597a-0c42-11f1-b2fa-42dde27851f2",23,["D",1771361613282],"script","export interface Book {\n isbn: string;\n title: string;\n priceThreshold: number;\n}\n\nexport const BOOKS: Book[] = [\n {\n isbn: \"9780415419970\",\n title: \"A Frequency Dictionary of Portuguese\",\n priceThreshold: 20.00,\n },\n {\n isbn: \"9780761137870\",\n title: \"660 Curries\",\n priceThreshold: 20.00,\n },\n {\n isbn: \"8508130627\",\n title: \"Para Gostar de Ler\",\n priceThreshold: 10.00,\n },\n];\n",[],[200],{"_106":209,"_97":101,"_163":210,"_165":-5,"_166":148,"_167":211,"_168":22,"_108":212,"_102":213,"_171":214,"_173":215,"_174":22,"_175":-5,"_176":216,"_100":217},"1c564704-0c43-11f1-bd5c-42dde27851f2","beed2fd6-ece6-11f0-b082-42dde27851f2",25,["D",1771361780262],18,"interval","import { email } from \"https://esm.town/v/std/email\";\nimport sqlite from \"https://esm.town/v/std/sqlite@14-main/main.ts\";\nimport { BOOKS } from \"./books.ts\";\n\nasync function ensureTable() {\n await sqlite.execute(`\n CREATE TABLE IF NOT EXISTS price_history (\n id INTEGER PRIMARY KEY AUTOINCREMENT,\n isbn TEXT NOT NULL,\n price REAL NOT NULL,\n checked_at TEXT NOT NULL DEFAULT (datetime('now'))\n )\n `);\n}\n\nasync function recordPrice(isbn: string, price: number) {\n await sqlite.execute({\n sql: `INSERT INTO price_history (isbn, price, checked_at) VALUES (?, ?, datetime('now'))`,\n args: [isbn, price],\n });\n}\n\nasync function checkBookPrice(book) {\n const url =\n `https://www.abebooks.com/servlet/SearchResults?isbn=${book.isbn}`;\n\n const response = await fetch(url, {\n headers: {\n \"User-Agent\":\n \"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36\",\n },\n });\n\n if (!response.ok) {\n return { book, lowestPrice: null, url, error: `HTTP ${response.status}` };\n }\n\n const html = await response.text();\n const prices = [];\n const regex = /item-price\"[^>]*>US?\\$?\\s*([0-9,]+(?:\\.[0-9]{2})?) 0 && price < 10000) prices.push(price);\n }\n\n if (prices.length === 0) {\n return { book, lowestPrice: null, url, error: \"No prices found\" };\n }\n\n return {\n book,\n lowestPrice: Math.min(...prices),\n prices: prices.sort((a, b) => a - b),\n url,\n };\n}\n\nexport async function main() {\n console.log(\"Checking book prices...\");\n await ensureTable();\n\n for (const book of BOOKS) {\n const result = await checkBookPrice(book);\n\n if (result.error) {\n console.log(`${book.title}: Error - ${result.error}`);\n continue;\n }\n\n console.log(\n `${book.title}: $${\n result.lowestPrice.toFixed(2)\n } (target: $${book.priceThreshold})`,\n );\n\n const hitTarget = result.lowestPrice <= book.priceThreshold;\n\n console.log({ hitTarget, dateTimeChecked: new Date().toLocaleString() });\n\n await recordPrice(book.isbn, result.lowestPrice);\n\n if (hitTarget) {\n await email({\n subject: hitTarget\n ? `Book Alert: ${book.title} is $${result.lowestPrice.toFixed(2)}!`\n : `Book Check: ${book.title} is $${result.lowestPrice.toFixed(2)}`,\n text: `${hitTarget ? \"HIT TARGET!\" : \"No hit yet.\"}\\n\\nLowest: $${\n result.lowestPrice.toFixed(2)\n }\\nYour target: $${book.priceThreshold.toFixed(2)}\\n\\nTop 5 prices: ${\n result.prices.slice(0, 5).map((p) => `$${p}`).join(\", \")\n }\\n\\nBuy: ${result.url}`,\n });\n console.log(\"Email sent!\");\n }\n }\n}\n",[],[101],{"_106":219,"_97":220,"_163":221,"_165":-5,"_166":148,"_167":222,"_168":169,"_108":223,"_102":33,"_171":185,"_173":224,"_174":22,"_175":-5,"_176":225,"_100":226},"b8e88e52-0c42-11f1-9d3d-42dde27851f2","deno.json","b8e88f1a-0c42-11f1-9d3d-42dde27851f2",22,["D",1771361613309],"{\n \"$schema\": \"https://raw.githubusercontent.com/denoland/deno/98f62cee78e85bfc47c62ed703777c6bc8794f1c/cli/schemas/config-file.v1.json\",\n \"lock\": false,\n \"compilerOptions\": {\n \"noImplicitAny\": false,\n \"strict\": true,\n \"types\": [\"https://www.val.town/types/valtown.d.ts\"],\n \"lib\": [\n \"dom\",\n \"dom.iterable\",\n \"dom.asynciterable\",\n \"deno.ns\",\n \"deno.unstable\"\n ]\n },\n \"lint\": {\n \"include\": [\"deno:/https/esm.town/**/*\"],\n \"rules\": {\n \"exclude\": [\"no-explicit-any\"]\n }\n },\n \"node_modules_dir\": false,\n \"experimental\": {\n \"unstable-node-globals\": true,\n \"unstable-temporal\": true,\n \"unstable-worker-options\": true,\n \"unstable-sloppy-imports\": true\n }\n}",[],[220],{"_106":228,"_97":229,"_163":230,"_165":-5,"_166":148,"_167":231,"_168":22,"_108":232,"_102":122,"_171":214,"_173":233,"_174":22,"_175":-5,"_176":234,"_100":235},"1c50f20e-0c43-11f1-bc32-42dde27851f2","digest.cron.ts","b8d56412-0c42-11f1-9959-42dde27851f2",24,["D",1771361780251],"import { email } from \"https://esm.town/v/std/email\";\nimport sqlite from \"https://esm.town/v/std/sqlite@14-main/main.ts\";\nimport { BOOKS } from \"./books.ts\";\n\nexport async function main() {\n console.log(\"Running weekly digest...\");\n\n const result = await sqlite.execute(`\n SELECT isbn, MIN(price) as min_price\n FROM price_history\n WHERE checked_at >= datetime('now', '-7 days')\n GROUP BY isbn\n `);\n\n const pricesByIsbn = new Map();\n for (const row of result.rows) {\n pricesByIsbn.set(row.isbn as string, row.min_price as number);\n }\n\n const lines: string[] = [];\n let anyBelowTarget = false;\n\n for (const book of BOOKS) {\n const minPrice = pricesByIsbn.get(book.isbn);\n const searchUrl = `https://www.abebooks.com/servlet/SearchResults?isbn=${book.isbn}`;\n\n if (minPrice == null) {\n lines.push(`${book.title} (ISBN: ${book.isbn})`);\n lines.push(` No price data this week`);\n lines.push(` Target: $${book.priceThreshold.toFixed(2)}`);\n lines.push(` Search: ${searchUrl}`);\n lines.push(\"\");\n continue;\n }\n\n const belowTarget = minPrice <= book.priceThreshold;\n if (belowTarget) anyBelowTarget = true;\n\n lines.push(`${belowTarget ? \"!!!\" : \" \"} ${book.title} (ISBN: ${book.isbn})`);\n lines.push(` Lowest this week: $${minPrice.toFixed(2)}`);\n lines.push(` Target: $${book.priceThreshold.toFixed(2)}`);\n lines.push(` ${belowTarget ? \"BELOW TARGET\" : \"Above target\"}`);\n lines.push(` Search: ${searchUrl}`);\n lines.push(\"\");\n }\n\n const subject = anyBelowTarget\n ? \"Weekly Book Digest - Deals Found!\"\n : \"Weekly Book Digest\";\n\n await email({\n subject,\n text: `Weekly Price Digest\\n${\"=\".repeat(40)}\\n\\n${lines.join(\"\\n\")}`,\n });\n\n console.log(\"Digest email sent!\");\n}\n",[],[229],"files",[160,179,189,198,208,218,227],"counts",{"_240":33,"_241":122,"_242":33,"_243":244,"_247":248},"pulls","branches","forks","envVars",{"_245":33,"_246":33},"count","emptyCount","connections",{"_245":33,"_249":33},"unfilledCount","contents",[],{"_106":209,"_97":101,"_163":210,"_165":-5,"_166":148,"_167":211,"_168":22,"_108":253,"_102":213,"_171":214,"_173":215,"_174":22,"_175":-5,"_100":254},["D",1771361780262],[101],"upstreamProject","upstreamBranch","emptyEnvVars","isNew","flags",[],"routes/_app.x.$handle.$name.branch.$branch.version.$version.code.$",{"_95":96,"_97":98,"_99":45,"_102":103,"_100":101,"_104":263,"_158":268,"_236":290,"_185":291,"_250":293,"_294":-5,"_295":-5,"_296":-5,"_297":-5,"_298":299,"_243":-5},{"_106":107,"_97":98,"_108":264,"_110":-5,"_111":22,"_112":113,"_114":-5,"_115":-5,"_14":116,"_117":-5,"_118":22,"_119":-5,"_120":-5,"_121":122,"_16":123,"_124":125,"_126":127,"_128":129,"_130":129,"_131":132,"_133":132,"_134":132,"_135":129,"_136":129,"_23":265,"_140":266,"_145":267,"_157":22},["D",1767913623802],{"_95":96,"_138":139},{"_95":96,"_142":139,"_14":116,"_143":144},{"_102":147,"_97":45,"_106":148,"_149":107,"_150":-5,"_151":-5,"_152":-5,"_153":-5,"_154":-5,"_155":98,"_156":96},[269,272,275,278,281,284,287],{"_106":161,"_97":162,"_163":164,"_165":-5,"_166":148,"_167":103,"_168":169,"_108":170,"_102":33,"_171":172,"_173":-5,"_174":22,"_175":-5,"_176":270,"_100":271},[],[162],{"_106":180,"_97":181,"_163":182,"_165":-5,"_166":148,"_167":183,"_168":169,"_108":184,"_102":33,"_171":185,"_173":186,"_174":22,"_175":-5,"_176":273,"_100":274},[],[181],{"_106":190,"_97":191,"_163":192,"_165":-5,"_166":148,"_167":193,"_168":169,"_108":194,"_102":33,"_171":185,"_173":195,"_174":22,"_175":-5,"_176":276,"_100":277},[],[191],{"_106":199,"_97":200,"_163":201,"_165":-5,"_166":148,"_167":202,"_168":22,"_108":203,"_102":33,"_171":204,"_173":205,"_174":22,"_175":-5,"_176":279,"_100":280},[],[200],{"_106":209,"_97":101,"_163":210,"_165":-5,"_166":148,"_167":211,"_168":22,"_108":212,"_102":213,"_171":214,"_173":215,"_174":22,"_175":-5,"_176":282,"_100":283},[],[101],{"_106":219,"_97":220,"_163":221,"_165":-5,"_166":148,"_167":222,"_168":169,"_108":223,"_102":33,"_171":185,"_173":224,"_174":22,"_175":-5,"_176":285,"_100":286},[],[220],{"_106":228,"_97":229,"_163":230,"_165":-5,"_166":148,"_167":231,"_168":22,"_108":232,"_102":122,"_171":214,"_173":233,"_174":22,"_175":-5,"_176":288,"_100":289},[],[229],[269,272,275,278,281,284,287],{"_106":209,"_97":101,"_163":210,"_165":-5,"_166":148,"_167":211,"_168":22,"_108":253,"_102":213,"_171":214,"_173":215,"_174":22,"_175":-5,"_100":292},[101],[],"upstream","pull","ahead","behind","templates",[],"actionData","errors"]

dubin

used_book_price_check