REST vs GraphQL

Perfect — let’s go through REST vs GraphQL, highlighting the differences, pros/cons, and when to use each in Node.js.

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1️⃣ Overview

Feature	REST	GraphQL
Endpoint style	Multiple endpoints (e.g., /users, /posts)	Single endpoint (e.g., /graphql)
Data fetching	Returns fixed data per endpoint	Client specifies exactly what data it needs
Over-fetching	Common problem	Avoided; only requested fields returned
Under-fetching	Common; may need multiple requests	Avoided; all required data fetched in one query
Type system	Implicit; no enforced schema	Strongly typed schema (GraphQL SDL)
Versioning	Versioned endpoints (v1, v2…)	Usually schema evolves without versioning
Caching	Easy with HTTP caching headers	More complex; needs custom caching logic
Real-time support	Usually with WebSockets or SSE	Built-in with subscriptions
Error handling	Standard HTTP codes (400, 404, 500)	Custom error objects in response

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2️⃣ Key Differences

a) Flexibility

• REST: Client cannot control response shape; fixed payload

• GraphQL: Client queries exactly what it needs

b) Number of Requests

• REST: May need multiple requests to fetch related data

• GraphQL: Can fetch nested data in a single request

c) Schema

• REST: Loosely defined, often implicit

• GraphQL: Explicit schema defines types, queries, mutations, subscriptions

d) Learning Curve

• REST: Simple, widely known

• GraphQL: Steeper learning curve, need to learn schema, resolvers, and tooling

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3️⃣ Example Comparison

REST

GET /users/1
{
  "id": 1,
  "name": "Tyson"
}
 
GET /users/1/posts
[
  { "id": 101, "title": "First Post" }
]

• Requires multiple requests to get user + posts

GraphQL

query {
  user(id: 1) {
    id
    name
    posts {
      id
      title
    }
  }
}

• Single request fetches user + posts exactly

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4️⃣ When to Use Which

Scenario	Recommended
Simple CRUD API, few clients	REST
Rapid frontend development, many clients	GraphQL
Real-time subscriptions & nested queries	GraphQL
Strict caching & simple API	REST
Evolving schema with frequent changes	GraphQL

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5️⃣ Node.js Integration

• REST: Express, Koa, Fastify

• GraphQL: Apollo Server, Express + express-graphql, Nexus Schema

• Both can coexist in the same app for hybrid APIs

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6️⃣ Key Takeaways

1. REST is simple, mature, and HTTP-standardized

2. GraphQL is flexible, client-driven, type-safe, and reduces over-fetching

3. Hybrid approach can work — REST for simple endpoints, GraphQL for complex data fetching

4. Tooling: Postman (REST) vs Playground/GraphiQL (GraphQL)

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Next, we could go through GraphQL best practices in Node.js, including resolvers, batching, caching, and schema design for scalable APIs.

Do you want me to cover that next?