Full route cache in NextJS - Step-by-Step Execution

Concept Flow - Full route cache

User requests a route

↓

Check if route cached

↓

Serve cached

↓

Return response

↓

Cache new route if rendered

This flow shows how Next.js checks if a route is cached, serves it if yes, or renders and caches it if no.

Execution Sample

NextJS

export const dynamic = 'force-static';

export default function Page() {
  return <h1>Hello, cached route!</h1>;
}

This Next.js page uses full route caching by forcing static rendering.

Execution Table

Step	Action	Cache Check	Render Action	Cache Update	Response
1	User requests /page	Cache miss	Render page component	Cache /page content	Send rendered HTML
2	User requests /page again	Cache hit	Skip rendering	No cache update	Send cached HTML
3	User requests /other	Cache miss	Render /other component	Cache /other content	Send rendered HTML
4	User requests /page again	Cache hit	Skip rendering	No cache update	Send cached HTML

💡 Execution stops when response is sent to user after serving cached or rendered content.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4
cache['/page']	empty	cached content	cached content	cached content	cached content
cache['/other']	empty	empty	cached content	cached content	cached content

Key Moments - 2 Insights

Why does the server skip rendering on the second request for the same route?

Because the cache check in step 2 finds the route content already cached, so it serves cached HTML without rendering again.

What happens if a new route is requested that is not cached?

The server renders the route component, caches the output, and then sends the response, as shown in step 3.

Visual Quiz - 3 Questions

Look at the execution table, what is the cache status when the user requests /page the first time?

A Cache hit

B Cache miss

C Cache empty

D Cache error

💡 Hint

Check Step 1 in the execution_table under 'Cache Check' column.

At which step does the server cache the /other route content?

A Step 3

B Step 2

C Step 1

D Step 4

💡 Hint

Look at 'Cache Update' column in execution_table for /other route.

If the cache was cleared before step 4, what would happen when /page is requested again?

A Cache hit, serve cached HTML

B Error, no response

C Cache miss, render and cache again

D Serve stale content

💡 Hint

Refer to variable_tracker showing cache state and execution_table steps for cache miss behavior.

Concept Snapshot

Full route cache in Next.js:
- Checks if route HTML is cached on request
- If cached, serves cached HTML immediately
- If not cached, renders route, caches output, then serves
- Improves performance by avoiding repeated rendering
- Use export const dynamic = 'force-static' to enable full route caching

Full Transcript

Full route caching in Next.js means the server saves the full HTML output of a route after rendering it once. When a user requests a route, the server first checks if the HTML is already cached. If yes, it sends the cached HTML immediately, skipping rendering. If no, it renders the page, caches the output, and then sends it. This speeds up responses for repeated requests. The example code uses 'export const dynamic = "force-static"' to tell Next.js to cache the full route. The execution table shows requests and cache hits or misses step by step. The variable tracker shows how the cache content changes after each request. Key moments clarify why rendering is skipped on cache hits and what happens on new routes. The quiz tests understanding of cache status and behavior during requests.