WebSocket transport in GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is WebSocket transport in GraphQL?

WebSocket transport is a way to keep a live connection open between client and server, allowing real-time data exchange for GraphQL subscriptions.

beginner

Why use WebSocket transport instead of HTTP for GraphQL subscriptions?

WebSocket keeps the connection open, so the server can send updates instantly without the client asking repeatedly, unlike HTTP which opens a new connection for each request.

intermediate

How does a GraphQL subscription work over WebSocket transport?

The client sends a subscription request over WebSocket. The server listens and sends data updates back through the same connection whenever data changes.

intermediate

Name one common protocol used for GraphQL subscriptions over WebSocket.

The 'graphql-ws' protocol is commonly used to handle GraphQL subscriptions over WebSocket connections.

intermediate

What happens if the WebSocket connection drops during a GraphQL subscription?

The client usually tries to reconnect automatically to keep receiving updates without losing data.

What is the main benefit of using WebSocket transport for GraphQL subscriptions?

A Real-time data updates without repeated requests

B Faster HTTP requests

C Better database storage

D Simpler query syntax

WebSocket transport keeps the connection open, allowing the server to push real-time updates without the client needing to ask repeatedly.

Which GraphQL operation commonly uses WebSocket transport?

A Introspection

B Query

C Subscription

D Mutation

Subscriptions use WebSocket transport to receive live updates from the server.

What does the client send first to start a GraphQL subscription over WebSocket?

A Query request

B Subscription request

C Mutation request

D Disconnect message

The client sends a subscription request to start receiving live data updates.

If the WebSocket connection drops, what usually happens?

A Server closes the database

B Subscription ends permanently

C Client sends a new HTTP request

D Client tries to reconnect automatically

Clients often try to reconnect automatically to keep the subscription active.

Which protocol is commonly used for GraphQL subscriptions over WebSocket?

A graphql-ws

B HTTP/2

C FTP

D SMTP

The 'graphql-ws' protocol is designed for GraphQL subscriptions over WebSocket.

Explain how WebSocket transport enables real-time updates in GraphQL subscriptions.

Think about how the connection stays open and data flows both ways.

Describe what happens when a WebSocket connection drops during a GraphQL subscription and how it is handled.

Consider how the client keeps the subscription alive despite connection issues.