whyhttp

HTTP mock server for use in tests. Starts a real server in a background thread, expectations are configured via a fluent builder API and verified automatically on drop.

Quick start

let server = whyhttp::Whyhttp::run();

server
    .when().path("/greet").method("GET")
    .should().header("x-token", "secret")
    .response().status(200u16).body("hello");

let resp = reqwest::blocking::Client::new()
    .get(format!("{}/greet", server.url()))
    .header("x-token", "secret")
    .send()
    .unwrap();

assert_eq!(resp.status(), 200u16);
assert_eq!(resp.text().unwrap(), "hello");

Routing vs. validation

Every expectation has two independent sets of matchers:

when — routing matchers: select which expectation handles the request. The first expectation whose matchers all pass wins.
should — validating matchers: run after routing. They never affect which response is returned — failures appear in the drop report.

let server = whyhttp::Whyhttp::run();

// Route only POST /orders, but assert the body separately.
server
    .when().path("/orders").method("POST")
    .should().body(r#"{"qty":1}"#)
    .response().status(201u16);

Drop behavior

When Whyhttp is dropped, all collected issues are printed and the test panics if anything is wrong — so a failing mock automatically fails the test. Possible issues:

Report	Cause
`NoCall`	Expectation was configured but never triggered
`MismatchTimes`	Expectation was triggered the wrong number of times
`UnmatchedRequest`	Request arrived but no expectation matched it
`Matcher`	Routing matched, but a `should` matcher failed

Matchers

Both when (routing) and should (validating) support the same set:

Method	Matches when…
`path(p)`	path equals `p`
`method(m)`	HTTP method equals `m` (case-insensitive)
`query(k, v)`	query param `k` equals `v`
`query_exists(k)`	query param `k` is present
`without_query(k)`	query param `k` is absent
`header(k, v)`	header `k` equals `v`
`header_exists(k)`	header `k` is present
`without_header(k)`	header `k` is absent
`body(b)`	body equals `b`
`without_body()`	body is empty

Call count assertion