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Qt开源网络库[8]-上传文件与超时处理

Qt君

发布于 2023-03-17 07:12:48

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代码可运行

文章被收录于专栏：跟Qt君学编程跟Qt君学编程

运行总次数：0

代码可运行

重构了部分代码并在此基础上添加"上传文件"和"超时处理"的功能

一个简单的使用例子：

HttpClient client;
client.get("https://qthub.com")
      .onSuccess([](QString result) { qDebug()<<"result:"<<result; })
      .onFailed([](QString err) { qDebug()<<"error:"<<err; })
      .exec();

1. 如何使用？

采用head-only的方式实现。只需在你的工程中包含 src 目录的 HttpClient.hpp 文件即可。
源码地址在文末。

2. 使用文档

2.1 使用信号槽的方式实现成功与失败的事件处理

接口:

Http请求返回成功的信号槽绑定

HttpRequest &onSuccess(const QObject *receiver, const char *method);
HttpRequest &onSuccess(std::function<void (QNetworkReply*)> lambda);
HttpRequest &onSuccess(std::function<void (QVariantMap)> lambda);
HttpRequest &onSuccess(std::function<void (QByteArray)> lambda);

Http请求返回失败的信号槽绑定

HttpRequest &onFailed(const QObject *receiver, const char *method);
HttpRequest &onFailed(std::function<void (QString)> lambda);
HttpRequest &onFailed(std::function<void (QNetworkReply::NetworkError)> lambda);
HttpRequest &onFailed(std::function<void (QNetworkReply*)> lambda);

例子:

static HttpClient client;
client.get("https://qthub.com")
      .onSuccess(this, SLOT(onSuccess(QString)))
      .onFailed(this, SLOT(onFailed(QString)))
      .exec(); // 执行Http操作

2.2 使用匿名函数的方式实现成功与失败的事件处理

接口:

Http请求返回成功的回调事件

HttpRequest &onSuccess(std::function<void (QNetworkReply*)> lambda);
HttpRequest &onSuccess(std::function<void (QVariantMap)> lambda);
HttpRequest &onSuccess(std::function<void (QByteArray)> lambda);

Http请求返回失败的回调事件

HttpRequest &onFailed(std::function<void (QString)> lambda);
HttpRequest &onFailed(std::function<void (QNetworkReply::NetworkError)> lambda);
HttpRequest &onFailed(std::function<void (QNetworkReply*)> lambda);

例子：

client.get("https://qthub.com")
      .onSuccess([](QString result) { qDebug()<<"result:"<<result.left(100); })
      .onFailed([](QString error) { qDebug()<<"error:"<<error; })
      .exec();

2.3 以信号槽的方式获取下载进度

接口:

HttpRequest &onDownloadProgress(const QObject *receiver, const char *method);

例子:

client.get("https://qthub.com")
      .onSuccess(this, SLOT(onSuccess(QString)))
      .onDownloadProgress(this, SLOT(onDownloadProgress(qint64, qint64)))
      .onFailed(this, SLOT(onFailed(QString)))
      .exec();

2.4 以匿名函数的方式获取下载进度

接口:

HttpRequest &onDownloadProgress(std::function<void (qint64, qint64)> lambda);

例子:

client.get("https://qthub.com")
      .onSuccess([](QString result) { qDebug()<<"result: " << result.left(10); })
      .onDownloadProgress([](qint64 bytesReceived, qint64 bytesTotal) {
          qDebug() << "lambda bytes received: " << bytesReceived
                   << "bytes total: " << bytesTotal;
       })
      .onFailed([](QString error) { qDebug()<<"error: " << error; })
      .exec();

2.5 post 上传文件并获取上传进度

接口:

HttpRequest &onUploadProgress(const QObject *receiver, const char *method);
HttpRequest &onUploadProgress(std::function<void (qint64, qint64)> lambda);

例子:

client.post("http://httpbin.org/post")
      .bodyWithFile("text_file", "helloworld.txt")
      .onUploadProgress([](qint64 bytesSent, qint64 bytesTotal) {
          qDebug() << "lambda bytes sent: " << bytesSent
                   << "bytes total: " << bytesTotal;
       })
      .onSuccess([](QString result) { qDebug()<<"result: " << result.left(100); })
      .onFailed([](QString error) { qDebug()<<"error: " << error; })
      .exec();

2.6 自定义超时时间和超时处理

timeout(ms)是设置超时时间，单位为毫秒(ms)。
onTimeout 为超时回调，当超时事件触发，自动调用 onTimeout 回调。

接口:

设置超时时间

HttpRequest &timeout(const int &msec = -1);

设置超时的回调函数

HttpRequest &onTimeout(const QObject *receiver, const char *method);
HttpRequest &onTimeout(std::function<void (QNetworkReply*)> lambda);
HttpRequest &onTimeout(std::function<void ()> lambda);

例子:

client.get("https://qthub.com")
      .onSuccess([](QString result) { qDebug()<<"result:"<<result.left(100); })
      .onFailed([](QString error) { qDebug()<<"error:"<<error; })
      .onTimeout([](QNetworkReply *) { qDebug()<<"timeout"; }) // 超时处理
      .timeout(1000) // 1s超时
      .exec();

2.7 由于 HttpClient 是异步实现，我们需要同步时可以这样做

接口:

HttpRequest &block();

例子:

client.get("https://qthub.com")
      .onSuccess(this, SLOT(onSuccess(QString)))
      .onFailed(this, SLOT(onFailed(QString)))
      .block() // 阻塞同步操作
      .exec(); // 执行Http操作

2.8 添加 header

接口:

HttpRequest &header(const QString &key, const QVariant &value);
HttpRequest &headers(const QMap<QString, QVariant> &headers);

例子:

client.post("https://example.com")
      .header("content-type", "application/json")
      .queryParam("key", "Hello world!")
      .body(R"({"user": "test"})")
      .onSuccess([](QString result){})
      .onFailed([](QString error){})
      .exec();

添加 params

接口:

HttpRequest &queryParam(const QString &key, const QVariant &value);
HttpRequest &queryParams(const QMap<QString, QVariant> &params);

例子:

client.get("https://example.com")
      .queryParam("key1", "value1")
      .queryParam("key2", "value2")
      .queryParam("key3", "value3")
      .onSuccess([](QString result){})
      .onFailed([](QString error){})
      .exec();

上面代码等同于:

client.get("https://example.com?key1=value1&key2=value2&key3=value3")
      .onSuccess([](QString result){})
      .onFailed([](QString error){})

2.9 添加 body

接口:

原始数据

HttpRequest &body(const QByteArray &raw);
HttpRequest &bodyWithRaw(const QByteArray &raw);

json 数据

HttpRequest &body(const QJsonObject &json);
HttpRequest &bodyWithJson(const QJsonObject &json);

表单数据

HttpRequest &body(const QVariantMap &formUrlencodedMap);
HttpRequest &bodyWithFormUrlencoded(const QVariantMap &keyValueMap);

混合消息

HttpRequest &body(QHttpMultiPart *multiPart);
HttpRequest &bodyWithMultiPart(QHttpMultiPart *multiPart);

文件消息

HttpRequest &body(const QString &key, const QString &file);
HttpRequest &bodyWithFile(const QString &key, const QString &file);
HttpRequest &bodyWithFile(const QMap<QString/*key*/, QString/*file*/> &fileMap);

例子:

发送原始数据

client.post("http://httpbin.org/post")
      .body("hello world")
      .onSuccess([](QString result){qDebug()<<result;})
      .onFailed([](QString error){qDebug()<<error;})
      .exec();

发送 json 数据

QJsonObject json
{
    {"property1", 1},
    {"property2", 2}
};

client.post("http://httpbin.org/post")
      .body(json)
      .onSuccess([](QString result){qDebug()<<result;})
      .onFailed([](QString error){qDebug()<<error;})
      .exec();

发送表单数据

QVariantMap map
{
    {"property1", 1},
    {"property2", 2}
};

client.post("http://httpbin.org/post")
      .body(map)
      .onSuccess([](QString result){qDebug()<<result;})
      .onFailed([](QString error){qDebug()<<error;})
      .exec();

发送混合消息

    QHttpMultiPart *multiPart = new QHttpMultiPart(QHttpMultiPart::FormDataType);

    QFile *file = new QFile("demo.txt");
    file->open(QIODevice::ReadOnly);
    file->setParent(multiPart);

    QString dispositionHeader = QString("form-data; name=\"%1\";filename=\"%2\"")
            .arg("text_file")
            .arg(file->fileName());

    QHttpPart part;
    part.setHeader(QNetworkRequest::ContentTypeHeader, QVariant("text/plain"));
    part.setHeader(QNetworkRequest::ContentDispositionHeader, dispositionHeader);
    part.setBodyDevice(file);

    multiPart->append(part);

    QString contentType = QString("multipart/form-data;boundary=%1").arg(multiPart->boundary().data());

HttpClient client;
client.post("http://httpbin.org/post")
      .header("content-type", contentType)
      .body(multiPart)
      .onSuccess([](QString result){ qDebug()<<result.left(1000); })
      .onFailed([](QString error){ qDebug()<<error; })
      .exec();

发送文件

HttpClient client;
client.post("http://httpbin.org/post")
      .body("text_file", "demo.txt")
      .body("image_file", "demo.jpg")
      .onSuccess([](QString result){ qDebug()<<result.left(1000); })
      .onFailed([](QString error){ qDebug()<<error; })
      .exec();

2.10 携带特定的用户数据到响应回调函数

接口:

HttpRequest &userAttribute(const QVariant &value);

例子:

client.get("http://httpbin.org/get")
      .userAttribute("Hello world!")
      .onSuccess([](QNetworkReply *reply) {
            QVariant value = reply->request().attribute(QNetworkRequest::User);
            qDebug()<< value.toString();
       })
      .onFailed([](QString error){ qDebug()<<error; })
      .exec();