CPRG-306 Week 13

API Database Integration

Topics

• Tagged Template Literals
• Serverless Relational Databases
• Connections
• API Integration

Tagged Template Literals

• allow you to parse and manipulate template strings with a custom function
• Commonly used for:
  • Creating domain-specific languages (DSLs)
  • Securely embedding expressions (e.g., SQL queries)
  • Localization and formatting

Example

// Define an asynchronous function to insert a new user
async function insertUser(email, name, age, role) {
  // Use the sql tagged template literal to construct the query
  // sql is a custom function that parses and executes the query
  // pretty interesting that you use backticks instead of parentheses for the function call!
  const result = await sql`
    INSERT INTO users (email, name, age, role)
    VALUES (${email}, ${name}, ${age}, ${role});
  `;
  return result;
}

Serverless Relational Databases

• hosted in the cloud and are managed by a cloud provider
• scalable and can be accessed from anywhere
• easy to set up and use
• cost-effective, as you only pay for what you use
• e.g. Neon, PlanetScale, FaunaDB, Supabase, Vercel Postgres

Connections

• Connection string
  • a string that contains the information required to connect to a database
• Connection pool
  • a cache of database connections maintained so that the connections can be reused when required
• Connection timeout
  • the maximum time that a connection can be idle before it is closed
• Cold start
  • the time it takes for a serverless database to start up when it is not being used

Coding Demo

• Create an API to perform CRUD operations on a serverless database
• Test the API
• Consume the API in a client application