QByteArray into JSON

t0msk

Hello,

I get from QNetworkReply this:

"\x1F\x8B\b\x00\x00\x00\x00\x00\x02\xFF\xAD\x90[\n\xC2""0\x10""E\xB7R\xF2\xAD&\x93""4}mF&\x93)\r\xB6MIZ\x8B\x88{WAp\x01\xFA{?\xCE""9\xDC\xBBX8M8\x86\xF9\"\xBA""B\f\xEB\xBA\xE4N\xCA}\xDFO\xD7\x90\xB6\xBC\xC6\x15\xC7\x13\xC5I\xF6""adI\rW\xC0H\xCEy\x03\xC8\x16\xD8*T\xAA""5lK\xDD:W9F\xD5\x97\xBE\xD1\x9At\xDD\x96\xE4mC\xAE\x87\x9AMe\x1A\x02\x89""3\x8E\xB7\x1C\xB2\x04k@\x1B\x05\xA0\xA4""8\x14\"q^\xE2\x9C\xF9L\xD1\xF3\xAB\x04^[\x1EP\xDB\xEA\x9D\xF5\xAB\xF6""c\x88[\"\xFE\x17/\x13\xCE\xE7\xE0\xFF\x81;~\xCF\x10\x8F'\n4\xB5V\x92\x01\x00\x00"

And it should be JSON, but it is in QByteArray and I need to convert it into JSON, how can I do it?

I tried this:

QByteArray reply = response->readAll();
reply.data();

And output from it is:
Output

SGaist

Hi,

Take a look at the JSON Support in Qt chapter in Qt's documentation.

Can you show what it is supposed to contain ?

ODБOï

hi,
https://forum.qt.io/topic/69728/can-t-get-json-file-from-qnetworkreply/2

t0msk

@SGaist It should contain something like:

{
  'response': 1,
  'scan': '123',
  'sha256': '54bc950d46a0d1aa71048a17c8275743209e6c17bdacfc5cb9601c9ce3ec9a71',
  'resource': '7647fcb7d772441a6d8504e4b21168b8',
}

@LeLev It doesn't help me, I have correct headers and I tried:

QByteArray reply = response->readAll();
QJsonDocument document = QJsonDocument::fromJson(response->readAll());
QJsonObject rootObj = document.object();

But in debugger I don't see any data in rootObj.

SGaist

Can you show how you request your data ? It looks like you don't get ASCII in return.

t0msk

@SGaist Of course, here it is:

QUrl url("www.example.com");
QUrlQuery query;

query.addQueryItem("apikey", "123");
query.addQueryItem("source", "123456");

url.setQuery(query.query());

QNetworkRequest request(url);

request.setRawHeader("Content-Type", "application/x-www-form-urlencoded");
request.setRawHeader("Accept-Encoding", "gzip, deflate");
request.setRawHeader("User-Agent", "gzip,  Test app");

QNetworkAccessManager *manager = new QNetworkAccessManager(this);

QObject::connect(manager, &QNetworkAccessManager::finished, this, &MainWindow::replyFinished);
manager->post(request, query.toString(QUrl::FullyEncoded).toUtf8());

jsulm

@t0msk You get (because you request it) gzip encoded data (see https://stackoverflow.com/questions/6059302/how-to-check-if-a-file-is-gzip-compressed).

request.setRawHeader("Accept-Encoding", "gzip, deflate");

You need to uncompress it first. See http://doc.qt.io/qt-5/qbytearray.html#qUncompress

t0msk

@jsulm So I changed it to:

QByteArray reply = qUncompress(response->readAll());
qDebug() << reply;

And I get:

qUncompress: Z_DATA_ERROR: Input data is corrupted
""

JonB

@t0msk
https://stackoverflow.com/questions/2690328/qt-quncompress-gzip-data deals with this.

TL;DR:

qUncompress uses the zlib uncompress, so it can only handle the zlib format, not the gzip format.
you'll need to write your own to functions to handle gzip data.

VRonin

You can use KArchive's KCompressionDevice to read GZip files: instead of response->readAll() you'll have KCompressionDevice(response,false,KCompressionDevice::GZip).readAll()