Function testProxyProtocolMatrix

caddytest/integration/proxyprotocol_test.go:475–533

testProxyProtocolMatrix is the shared implementation for the proxy protocol tests. It: 1. Starts a go-proxyproto-wrapped backend. 2. Configures Caddy as a reverse proxy with the given PROXY protocol version and transport versions. 3. Sends numRequests GET requests through Caddy and asserts 200 OK e

(t *testing.T, ppVersion string, transportVersions []string, numRequests int)

//  4. Asserts the backend recorded at least one PROXY header whose source host
//     is 127.0.0.1 (the loopback address used by the test client).
func testProxyProtocolMatrix(t *testing.T, ppVersion string, transportVersions []string, numRequests int) {
	t.Helper()

	backend := newProxyProtoBackend(t)
	listenPort := freePort(t)

	tester := caddytest.NewTester(t)
	tester.WithDefaultOverrides(caddytest.Config{
		AdminPort: 2999,
	})
	cfg := proxyProtoConfig(listenPort, backend.addr(), ppVersion, transportVersions)
	tester.InitServer(cfg, "json")

	// If the test is h2c-only (no "1.1" in versions), reconfigure the test
	// client transport to use unencrypted HTTP/2 so we actually exercise the
	// h2c code path through Caddy.
	if slices.Contains(transportVersions, "h2c") && !slices.Contains(transportVersions, "1.1") {
		tr, ok := tester.Client.Transport.(*http.Transport)
		if ok {
			tr.Protocols = new(http.Protocols)
			tr.Protocols.SetHTTP1(false)
			tr.Protocols.SetUnencryptedHTTP2(true)
		}
	}

	proxyURL := fmt.Sprintf("http://127.0.0.1:%d/", listenPort)

	for i := 0; i < numRequests; i++ {
		resp, err := tester.Client.Get(proxyURL)
		if err != nil {
			t.Fatalf("request %d/%d: GET %s: %v", i+1, numRequests, proxyURL, err)
		}
		resp.Body.Close()
		if resp.StatusCode != http.StatusOK {
			t.Errorf("request %d/%d: expected status 200, got %d", i+1, numRequests, resp.StatusCode)
		}
	}

	// The backend must have seen at least one PROXY header.  For h1, there is
	// one per request; for h2c, requests share the same connection so only one
	// header is written at connection establishment.
	addrs := backend.recordedAddrs()
	if len(addrs) == 0 {
		t.Fatalf("backend recorded no PROXY protocol addresses (expected at least 1)")
	}

	// Every PROXY-decoded source address must be the loopback address since
	// the test client always connects from 127.0.0.1.
	for i, addr := range addrs {
		host, _, err := net.SplitHostPort(addr)
		if err != nil {
			t.Errorf("addr[%d] %q: SplitHostPort: %v", i, addr, err)
			continue
		}
		if host != "127.0.0.1" {
			t.Errorf("addr[%d]: expected source 127.0.0.1, got %q", i, host)
		}
	}