geektutu/7days-golang · error

bad request

Error message

bad request

What it means

HTTP 400 response in HTTPPool.ServeHTTP: the URL path after basePath does not split into exactly two parts "<groupname>/<key>", so the peer request is malformed. It fires on paths missing the key segment or with unexpected slash structure.

Source

Thrown at gee-cache/day6-single-flight/geecache/http.go:51

		basePath: defaultBasePath,
	}
}

// Log info with server name
func (p *HTTPPool) Log(format string, v ...interface{}) {
	log.Printf("[Server %s] %s", p.self, fmt.Sprintf(format, v...))
}

// ServeHTTP handle all http requests
func (p *HTTPPool) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if !strings.HasPrefix(r.URL.Path, p.basePath) {
		panic("HTTPPool serving unexpected path: " + r.URL.Path)
	}
	p.Log("%s %s", r.Method, r.URL.Path)
	// /<basepath>/<groupname>/<key> required
	parts := strings.SplitN(r.URL.Path[len(p.basePath):], "/", 2)
	if len(parts) != 2 {
		http.Error(w, "bad request", http.StatusBadRequest)
		return
	}

	groupName := parts[0]
	key := parts[1]

	group := GetGroup(groupName)
	if group == nil {
		http.Error(w, "no such group: "+groupName, http.StatusNotFound)
		return
	}

	view, err := group.Get(key)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

View on GitHub (pinned to cf36443821)

Solutions

1. Return a 400 status with a clear message instructing the client to use the URL format /<basePath>/<groupname>/<key>
2. Log the received path server-side to aid debugging of malformed requests
3. Add client-side URL construction helpers so callers build valid cache paths instead of hand-crafting them

When it happens

Trigger: Thrown at gee-cache/day6-single-flight/geecache/http.go:51 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of geektutu/7days-golang@cf36443821 (2026-09-03). Data as JSON: /api/errors/208342420bf2235f. Report an issue: GitHub.