HTTP Caching
HTTP caching is the set of rules and headers that let browsers, CDNs, and proxies store responses and reuse them for later matching requests. Cache-Control defines freshness, ETag and Last-Modified enable conditional revalidation, and correct status handling avoids downloading unchanged API payloads.
Technical Architecture & Deep-Dive
Caching is not only for static files. Public GET APIs with stable URLs can be cached at the edge when responses exclude user-specific secrets and carry explicit TTLs. Shared caches require careful cache keys so one user never sees another user data.
A complete HTTP caching strategy combines max-age and s-maxage, stale-while-revalidate for background refresh, ETag validation for bandwidth savings, and targeted invalidation when upstream data changes. Edge gateways often add missing headers on third-party responses to unlock caching the provider omitted.
Key Architectural Benefits
Implement HTTP Caching at the Edge
Deploy lightweight API aggregation, edge caching, and secret injection in minutes without Docker containers or complex servers.
Frequently Asked Questions
Q:Can POST responses be HTTP cached?
Shared caches normally cache only GET and HEAD unless explicitly configured otherwise. POST is uncacheable by default because it is not assumed idempotent.
Related Architecture Concepts
Cache-Control is an HTTP response header that tells browsers, CDNs, and proxies whether and how long a response may be cached. Directives such as max-age, s-maxage, private, no-store, and stale-while-revalidate control freshness and sharing for every cached copy.
An ETag, or entity tag, is an HTTP response header containing a version identifier for a resource. Clients send it back in an If-None-Match header, and if the resource has not changed, the server replies with 304 Not Modified and no body, saving bandwidth.
A Content Delivery Network (CDN) is a globally distributed network of servers that caches and serves content from locations close to users. By answering requests from a nearby point of presence instead of a distant origin, a CDN reduces latency, offloads origin traffic, and absorbs traffic spikes.
Cache warming is proactively fetching or refreshing cached content before users request it, so edge caches already hold responses when traffic arrives. For APIs, scheduled jobs or deploy hooks can hit important GET endpoints to populate CDN and edge cache tiers and avoid slow cold misses during launches or peak events.
Ready-to-Use Edge Recipes
To solve rest api edge cdn caching guide, never execute unauthenticated requests or embed private tokens directly in client bundles. RealComposer acts as a sub-10ms edge gateway running on Cloudflare Workers that securely injects credentials from your Secret Vault, normalizes responses, and prevents unauthorized API usage. Route calls through your RealComposer edge URL to guarantee complete privacy, robust origin validation, and low mobile latency.
To solve stale while revalidate caching for third party rest apis, never execute unauthenticated requests or embed private tokens directly in client bundles. RealComposer acts as a sub-10ms edge gateway running on Cloudflare Workers that securely injects credentials from your Secret Vault, normalizes responses, and prevents unauthorized API usage. Route calls through your RealComposer edge URL to guarantee complete privacy, robust origin validation, and low mobile latency.