Function write

js/worker.js:89–140

(chunk, controller)

    // ws --> remote
    readableWebSocketStream.pipeTo(new WritableStream({
        async write(chunk, controller) {
            if (isDns && udpStreamWrite) {
                return udpStreamWrite(chunk);
            }
            if (remoteSocketWapper.value) {
                const writer = remoteSocketWapper.value.writable.getWriter()
                await writer.write(chunk);
                writer.releaseLock();
                return;
            }

            const {
                hasError,
                message,
                portRemote = 443,
                addressRemote = '',
                rawDataIndex,
                vlessVersion = new Uint8Array([0, 0]),
                isUDP,
            } = processVlessHeader(chunk, userID);
            address = addressRemote;
            portWithRandomLog = `${portRemote}--${Math.random()} ${isUDP ? 'udp ' : 'tcp '
                } `;
            if (hasError) {
                // controller.error(message);
                throw new Error(message); // cf seems has bug, controller.error will not end stream
                // webSocket.close(1000, message);
                return;
            }
            // if UDP but port not DNS port, close it
            if (isUDP) {
                if (portRemote === 53) {
                    isDns = true;
                } else {
                    // controller.error('UDP proxy only enable for DNS which is port 53');
                    throw new Error('UDP proxy only enable for DNS which is port 53'); // cf seems has bug, controller.error will not end stream
                    return;
                }
            }
            // ["version", "附加信息长度 N"]
            const vlessResponseHeader = new Uint8Array([vlessVersion[0], 0]);
            const rawClientData = chunk.slice(rawDataIndex);

            // TODO: support udp here when cf runtime has udp support
            if (isDns) {
                const { write } = await handleUDPOutBound(webSocket, vlessResponseHeader, log);
                udpStreamWrite = write;
                udpStreamWrite(rawClientData);
                return;
            }
            handleTCPOutBound(remoteSocketWapper, addressRemote, portRemote, rawClientData, webSocket, vlessResponseHeader, log);
        },
        close() {
            log(`readableWebSocketStream is close`);
        },