The Full Lifecycle of an HTTPS API Request
This planned lesson follows a single fetch() call from the browser to an API and back. It starts with URL parsing, shows how a hostname can resolve to an address, and then compares the setup for HTTP/2 over TCP with HTTP/3 over QUIC. The lesson pauses at TLS to explain what the client verifies and which connection endpoint receives the protection.
The second half follows the HTTP request through a possible edge proxy, into application code, and through a dependency call. It ends with the response path, connection reuse, and a short timing exercise that separates DNS, connection setup, server work, and body transfer. The companion article and interactive request flow provide the written map.
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