#跟着小白一起学鸿蒙#WebSocket的使用和流程分析 原创 精华

//导入websocket接口
import webSocket from '@ohos.net.webSocket'
//websocket的基本接口函数
connect(url: string, callback: AsyncCallback<boolean>): void;
send(data: string | ArrayBuffer, callback: AsyncCallback<boolean>): void;
close(callback: AsyncCallback<boolean>): void;
1.
2.
3.
4.
5.
6.

    let promise = socket.connect(url)
    promise.then((value) => {
      Logger.info(TAG, `connect success`)
    }).catch((err) => {
      Logger.info(TAG, `connect fail, error:${JSON.stringify(err)}`)
    })
    socket.on('open', (err, value) => {
      prompt.showToast({ message: '连接成功', duration: 1500 })
    })
    socket.on('message', (err, value) => {
      Logger.info(TAG, `on message, value = ${value}`)
    })
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.

//foundation/communication/netstack/frameworks/js/napi/websocket/websocket_module/src/websocket_module.cpp
std::initializer_list<napi_property_descriptor> properties = {
    DECLARE_NAPI_FUNCTION(WebSocket::FUNCTION_CONNECT, WebSocket::Connect),
    DECLARE_NAPI_FUNCTION(WebSocket::FUNCTION_SEND, WebSocket::Send),
    DECLARE_NAPI_FUNCTION(WebSocket::FUNCTION_CLOSE, WebSocket::Close),
    DECLARE_NAPI_FUNCTION(WebSocket::FUNCTION_ON, WebSocket::On),
    DECLARE_NAPI_FUNCTION(WebSocket::FUNCTION_OFF, WebSocket::Off),
};
ModuleTemplate::DefineClass(env, exports, properties, INTERFACE_WEB_SOCKET);
1.
2.
3.
4.
5.
6.
7.
8.
9.

//foundation/communication/netstack/frameworks/js/napi/websocket/async_work/src/websocket_async_work.cpp
//初始化libwebsocket需要的callback
static const lws_protocols LWS_PROTOCOLS[] = {
    {"lws-minimal-client", WebSocketExec::LwsCallback, 0, 0},
    {nullptr, nullptr, 0, 0}, // this line is needed
};

//填装websocket上下文信息
static inline void FillContextInfo(lws_context_creation_info &info)
{
    info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT;
    info.port = CONTEXT_PORT_NO_LISTEN;
    info.protocols = LWS_PROTOCOLS;
    info.fd_limit_per_thread = FD_LIMIT_PER_THREAD;
}

void WebSocketAsyncWork::ExecConnect(napi_env env, void *data)
{
    BaseAsyncWork::ExecAsyncWork<ConnectContext, WebSocketExec::ExecConnect>(env, data);
}

void WebSocketAsyncWork::ExecSend(napi_env env, void *data)
{
    BaseAsyncWork::ExecAsyncWork<SendContext, WebSocketExec::ExecSend>(env, data);
}

void WebSocketAsyncWork::ExecClose(napi_env env, void *data)
{
    BaseAsyncWork::ExecAsyncWork<CloseContext, WebSocketExec::ExecClose>(env, data);
}
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.

//正确连接
I C015b0/NetMgrSubsystem: NETSTACK [connect_context.cpp 43] ConnectContext NapiUtils::GetValueType(GetEnv(), params[1]) == napi_function
I C015b0/NetMgrSubsystem: NETSTACK [module_template.h 61] js params parse OK ? 1
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 471] begin connect, parse url
E C015b0/NetsysNativeService: [HookSocket-(netsys_sock_client.cpp:45)]musl create socket failed
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 228] start service
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 533] ConnectCallback connect success

//错误连接
I C015b0/NetMgrSubsystem: NETSTACK [connect_context.cpp 43] ConnectContext NapiUtils::GetValueType(GetEnv(), params[1]) == napi_function
I C015b0/NetMgrSubsystem: NETSTACK [module_template.h 61] js params parse OK ? 1
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 471] begin connect, parse url
E C015b0/NetsysNativeService: [HookSocket-(netsys_sock_client.cpp:45)]musl create socket failed
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 358] LwsCallbackClientConnectionError DNS NXDOMAIN
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 427] LwsCallbackWsiDestroy
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 515] ExecConnect websocket connect failed
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 433] LwsCallbackProtocolDestroy
I C015b0/NetMgrSubsystem: NETSTACK [websocket_exec.cpp 530] ConnectCallback connect failed
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.