Method encodeHeader

test/rawConnWrapper.go:164–219

encodeHeader is for usage on client side to write request header. encodeHeader encodes headers and returns their HPACK bytes. headers must contain an even number of key/value pairs. There may be multiple pairs for keys (e.g. "cookie"). The :method, :path, and :scheme headers default to GET, / and

(headers ...string)

// multiple pairs for keys (e.g. "cookie").  The :method, :path, and
// :scheme headers default to GET, / and https.
func (rcw *rawConnWrapper) encodeHeader(headers ...string) []byte {
	if len(headers)%2 == 1 {
		panic("odd number of kv args")
	}

	rcw.headerBuf.Reset()

	if len(headers) == 0 {
		// Fast path, mostly for benchmarks, so test code doesn't pollute
		// profiles when we're looking to improve server allocations.
		rcw.encodeHeaderField(":method", "GET")
		rcw.encodeHeaderField(":path", "/")
		rcw.encodeHeaderField(":scheme", "https")
		return rcw.headerBuf.Bytes()
	}

	if len(headers) == 2 && headers[0] == ":method" {
		// Another fast path for benchmarks.
		rcw.encodeHeaderField(":method", headers[1])
		rcw.encodeHeaderField(":path", "/")
		rcw.encodeHeaderField(":scheme", "https")
		return rcw.headerBuf.Bytes()
	}

	pseudoCount := map[string]int{}
	keys := []string{":method", ":path", ":scheme"}
	vals := map[string][]string{
		":method": {"GET"},
		":path":   {"/"},
		":scheme": {"https"},
	}
	for len(headers) > 0 {
		k, v := headers[0], headers[1]
		headers = headers[2:]
		if _, ok := vals[k]; !ok {
			keys = append(keys, k)
		}
		if strings.HasPrefix(k, ":") {
			pseudoCount[k]++
			if pseudoCount[k] == 1 {
				vals[k] = []string{v}
			} else {
				// Allows testing of invalid headers w/ dup pseudo fields.
				vals[k] = append(vals[k], v)
			}
		} else {
			vals[k] = append(vals[k], v)
		}
	}
	for _, k := range keys {
		for _, v := range vals[k] {
			rcw.encodeHeaderField(k, v)
		}
	}
	return rcw.headerBuf.Bytes()
}

func (rcw *rawConnWrapper) writeHeaders(p http2.HeadersFrameParam) error {