sending json via QNetwork (using Python)

[Kris Revi]

how do i send json via QNetwork? all i know is to set the header to "application/json"

from PyQt5 import QtCore, QtWidgets, QtNetwork
from PyQt5.QtCore import QUrl, QTimer

class software(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        QtWidgets.QWidget.__init__(self, parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)

	self.nam = QtNetwork.QNetworkAccessManager()
	self.nam.finished.connect(self.handlePostResponse)

	self.doPost()

    def doPost(self):
        data = QtCore.QByteArray()
        data.append("selectedPattern=2")

        request = QtNetwork.QNetworkRequest(QtCore.QUrl("http://192.168.10.2/selectPattern"))
        request.setHeader(QtNetwork.QNetworkRequest.ContentTypeHeader, "application/x-www-form-urlencoded")

        self.nam.post(request, data)

    def handlePostResponse(self, reply):
        er = reply.error()

        if er == QtNetwork.QNetworkReply.NoError:
            print("No Error")
            print(reply.readAll())

        else:
            print("Error occurred: ", er)
            print(reply.errorString())


if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)

    myapp = software()
    myapp.show()
    sys.exit(app.exec_())

[jsulm]

@Kris-Revi So, you want to send HTTP POST request? If so: https://doc.qt.io/qt-5/qnetworkaccessmanager.html#post-1 data (second parameter) is where you pass your JSON.

[Kris Revi]

@jsulm yes and so just make data variable json with QJsonDocument?

[Christian Ehrlicher]

@Kris-Revi said in sending json via QNetwork:

yes and so just make data variable json with QJsonDocument?

And now please express this in a sentence which we are able to understand.

[jsulm]

@Kris-Revi https://doc.qt.io/qt-5/qjsondocument.html#toJson

[Kris Revi]

i've been googling my ass off but support for python Qt is small to non existent, can't find any example :/

[Christian Ehrlicher]

@Kris-Revi said in sending json via QNetwork (using Python):

i've been googling my ass off but support for python Qt is small to non existent

And what problem do you have? You don't ask questions we really understand but we try to help as best as we can and then you ignore our links...

[Kris Revi]

@Christian-Ehrlicher how do i make "doPost" send json like this

data = {"key": value1}

using QJsonDocument

[Christian Ehrlicher]

Create a QJsonObject with the values you want, the use a QJsonDocument to convert it to a QByteArray. See https://doc.qt.io/qt-5/qtcore-serialization-savegame-example.html for an example.

[Kris Revi]

@Christian-Ehrlicher what am i doing wrong? :/

json = QJsonDocument.object()
json["selectedPattern"] = "2"

document = QJsonDocument(json)
doc = document.toJson(document)
print(doc)

Error :

object(self): first argument of unbound method must have type 'QJsonDocument'

[Kris Revi]

anyone? :)

[SGaist]

Please show some patience and allow at least 24 hours to pass before bumping your own thread. This forum is run by volunteers who may not live in the same timezone as you.

As for your error, did you check what it means ?

[Kris Revi]

@SGaist ok sorry for that :) i'll keep that in mind!

[Kris Revi]

@SGaist i tried googling but didn't find anything on the error :S

[SGaist]

The QJsonDocument::toJson overload you want to use takes no argument.

[Kris Revi]

@SGaist ok this is what i got sofar

    def doPost(self):
        try:
            json = {'selectedPatter': '2'}
            document = QJsonDocument(json)

            print(document.toJson())

            request = QtNetwork.QNetworkRequest(QtCore.QUrl("http://192.168.10.2/selectPattern"))
            request.setHeader(QtNetwork.QNetworkRequest.ContentTypeHeader, "application/json")

            self.nam2.post(request, document.toJson())
        except Exception as e:
            print(e)

    def handlePostResponse(self, reply):
        er = reply.error()

        if er == QtNetwork.QNetworkReply.NoError:
            print("No Error")
            print(reply.readAll())

        else:
            print("Error occurred: ", er)
            print(reply.errorString())

the print out in doPost function looks weird :S this b' and \n

b'{\n    "selectedPatter": "2"\n}\n'

but the print in handlePostResponse function is

No Error
b''

[SGaist]

No it does not, it's a string, or rather bytes, containing a simple json document containing one field.

As for the reply you are getting, what are you expecting ? Is the service supposed to return something ?

[Kris Revi]

This post is deleted!