Qt REST Client (Beta)

#ifndef SKIDKZAPI_H
#define SKIDKZAPI_H

#include "apibase.h"
#include "usingleton.h"
#include <QtQml>

class SkidKZApi : public APIBase, public uSingleton<SkidKZApi>
{
    Q_OBJECT
public:
    SkidKZApi();

    //api methods
    //get list of objects
    QNetworkReply *getCoupons(QStringList sort, Pagination *pagination, 
                                QVariantMap filters = QVariantMap(), 
                                QStringList fields = QStringList());
    //get full data for specified item
    QNetworkReply *getCouponDetail(QString id);
};

#endif // SKIDKZAPI_H

#include "skidkzapi.h"
#include <QFile>
#include <QTextStream>
#include <QUrlQuery>

SkidKZApi::SkidKZApi() : APIBase(0), uSingleton<SkidKZApi>(*this)
{
    //Base URL used for all API calls for this example
    setBaseUrl("http://api.skid.kz");

    //You may specify auth token for each API call. And you may write your own api method for authetification
    setAuthToken("Bearer 8aef452ee3b32466209535b96d456b06");
}

//In this methods we get list of objects, based on specified page number, filters, sort and fileds list.
//We can fetch all fields or only needed in our list.
QNetworkReply *SkidKZApi::getCoupons(QStringList sort, Pagination *pagination, 
                                      QVariantMap filters, QStringList fields)
{
    //URL and GET parameters
    QUrl url = QUrl(baseUrl()+"/v1/coupon");
    QUrlQuery query;

    //Specify filters GET param
    if (!sort.isEmpty()) {
        query.addQueryItem("sort", sort.join(","));
    }

    //Specify pagination. We use pagination type from model.
    switch(pagination->policy()) {
    case Pagination::PageNumber:
        query.addQueryItem("per-page", QString::number(pagination->perPage()));
        query.addQueryItem("page", QString::number(pagination->currentPage()));
        break;
    case Pagination::None:
    case Pagination::Infinity:
    case Pagination::LimitOffset:
    case Pagination::Cursor:
    default:
        break;
    }

    //if we need to filter our model, we use filters.
    //Be careful, if you use this methods, your curent pagintaion wil be broken
    //and you must full reaload your model data when you specify new filters
    if (!filters.isEmpty()) {
        QMapIterator<QString, QVariant> i(filters);
        while (i.hasNext()) {
            i.next();
            query.addQueryItem(i.key(), i.value().toString());
        }
    }

    //We may to get all or spicified fields in this method.
    if (!fields.isEmpty()) {
        query.addQueryItem("fields", fields.join(","));
    }

    url.setQuery(query.query());

    QNetworkReply *reply = get(url);

    return reply;
}

//If we fetch e.g. 3 of 10 fields in our 'getCoupons' methods,
//we may to get full information from needed item by it ID
QNetworkReply *SkidKZApi::getCouponDetail(QString id)
{
    if (id.isEmpty()) {
        qDebug() << "ID is empty!";
        return 0;
    }

    QUrl url = QUrl(baseUrl()+"/v1/coupon/"+id);

    QNetworkReply *reply = get(url);

    return reply;
}

#ifndef COUPONMODEL_H
#define COUPONMODEL_H

//We use JSON API version
#include "jsonrestlistmodel.h"

//We use our Skid.KZ API
#include "api/skidkzapi.h"

class CouponModel : public JsonRestListModel
{
    Q_OBJECT
public:
    explicit CouponModel(QObject *parent = 0);

    static void declareQML() {
        JsonRestListModel::declareQML();
        qmlRegisterType<CouponModel>("com.github.qtrest.coupons", 1, 0, "CouponModel");
    }
protected:
    QNetworkReply *fetchMoreImpl(const QModelIndex &parent);
    QNetworkReply *fetchDetailImpl(QString id);
    QVariantMap preProcessItem(QVariantMap item);

    APIBase *apiInstance();
};

#endif // COUPONMODEL_H

#include "couponmodel.h"

CouponModel::CouponModel(QObject *parent) : JsonRestListModel(parent)
{

}

APIBase *CouponModel::apiInstance()
{
    return &SkidKZApi::instance();
}

QNetworkReply *CouponModel::fetchMoreImpl(const QModelIndex &parent)
{
    return SkidKZApi::instance().getCoupons(sort(), pagination(), filters(), fields());
}

QNetworkReply *CouponModel::fetchDetailImpl(QString id)
{
    return SkidKZApi::instance().getCouponDetail(id);
}

//Data management and preparation is function of Backend developer, but if he or she 
//is do not want to deal with data preparation, you may to prepare each item yourself
QVariantMap CouponModel::preProcessItem(QVariantMap item)
{
    QDate date = QDateTime::fromString(item.value("createTimestamp").toString(), 
                                        "yyyy-MM-dd hh:mm:ss").date();
    item.insert("createDate", date.toString("dd.MM.yyyy"));

    QString originalCouponPrice = item.value("originalCouponPrice").toString().trimmed();
    if (originalCouponPrice.isEmpty()) { originalCouponPrice = "?"; }
    QString discountPercent = item.value("discountPercent").toString()
    .trimmed().remove("—").remove("-").remove("%");
    if (discountPercent.isEmpty()) { discountPercent = "?"; }
    QString originalPrice = item.value("originalPrice").toString().trimmed();
    if (originalPrice.isEmpty()) { originalPrice = "?"; }
    QString discountPrice = item.value("discountPrice").toString().remove("тг.").trimmed();
    if (discountPrice.isEmpty()) { discountPrice = "?"; }

    QString discountType = item.value("discountType").toString();
    QString discountString = tr("Undefined Type");
    if (discountType == "freeCoupon" || discountType == "coupon") {
        discountString = tr("Coupon: %1. Discount: %2%")
        .arg(originalCouponPrice).arg(discountPercent);
    } else if (discountType == "full") {
        discountString = tr("Cost: %1. Certificate: %2. Discount: %3%")
        .arg(originalPrice).arg(discountPrice).arg(discountPercent);
    }

    item.insert("discountString", discountString);

    return item;
}