Workshop: Build serverless edge applications with Cloudflare Workers and Fauna

npm install -g wrangler@latest

fauna create-database mydb

fauna project init

wrangler deploy

export default {
  async fetch(
    request: Request,
    env: Env,
    ctx: ExecutionContext
  ): Promise<Response> {
    // Extract the method from the request
    const { method, url } = request;
		const { pathname } = new URL(url);

		// Route the request based on path and method
    if (method === "POST" && pathname.startsWith("/dynamic/")) {
      const collectionName = pathname.split("/dynamic/")[1];
			if (!collectionName) {
				return new Response("Missing collection name", { status: 400 });
			}
      return createDynamicQuery(request, env, collectionName);
    }

		switch (method) {
			case "GET":
				return getAllProducts(request, env);
			case "POST":
				return createNewProduct(request, env);
			default:
				return new Response("Method Not Allowed", { status: 405 });
		}
	},
};

// ... rest of the code

// Handle dynamic FQL queries
async function createDynamicQuery(
  request: Request,
  env: Env,
  collectionName: string
): Promise<Response> {
  const body = await request.json() as any;
  const { operation } = body;

  switch (operation) {
    case "create":
      return createDocument(collectionName, body, env);
    case "update":
      return updateDocument(collectionName, body, env);
    case "delete":
      return deleteDocument(collectionName, body, env);
    default:
      return new Response("Invalid operation", { status: 400 });
  }
}

// ... rest of the code

async function createDocument(
  collectionName: string,
  body: any,
  env: Env
): Promise<Response> {
  if (collectionName === "Product") {
    // Delegate to createNewProduct for specific "Product" creation logic
    return createNewProduct(body.fields, env);
  }

  const client = new Client({ secret: env.FAUNA_SECRET });
  try {
    // Pass the constructed FQL string inside the `fql` template literal
    const result = await client.query(fql`
			Collection(${collectionName}).create(${body.fields})
		`);
    return new Response(JSON.stringify(result.data));
  } catch (error) {
    console.error(error);
    if (error instanceof FaunaError) {
      return new Response(error.message, { status: 500 });
    }
    return new Response("An error occurred when creating the document.", { status: 500 });
  }
}

async function updateDocument(
  collectionName: string,
  body: any,
  env: Env
): Promise<Response> {
  const client = new Client({ secret: env.FAUNA_SECRET });
  const { id, fields } = body;
  try {
    const result = await client.query(fql`
			Collection(${collectionName}).byId(${id}).update(${fields})
		`);
    return new Response(JSON.stringify(result.data));
  } catch (error) {
    if (error instanceof FaunaError) {
      return new Response(error.message, { status: 500 });
    }
    return new Response("An error occurred", { status: 500 });
  }
}

async function deleteDocument(
  collectionName: string,
  body: any,
  env: Env
): Promise<Response> {
  const client = new Client({ secret: env.FAUNA_SECRET });
  const { id } = body;
  try {
    const result = await client.query(fql`
			Collection(${collectionName}).byId(${id}).delete()
		`);
    return new Response(JSON.stringify(result.data));
  } catch (error) {
    if (error instanceof FaunaError) {
      return new Response(error.message, { status: 500 });
    }
    return new Response("An error occurred", { status: 500 });
  }
}

wrangler dev

curl -X POST http://localhost:8787/dynamic/Product \
  -d '{
    "operation": "create",
    "fields": {
      "name": "Tablet",
      "description": "A tablet computer",
      "price": 200,
      "stock": 15,
      "category": "Electronics"
    }
  }'

wrangler deploy