Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads

[gunraidan]

So I'm trying to make a Pokedex that doesn't freeze when pulling data from the website's API.

Full code of main window and main function.
Abilities.py that has the load abilities thread.
The Pokemon Dictionary in Pokecache is just a blank dictionary.

This a work in progress so obviously the GUI isn't going to look beautiful, but you should get the gist of it.

This is an example of me running the program. It seems to work fine but after hitting it multiple times it will crash:

As you can see the program ran fine but crashed. The log looks as such:

Ability Thread: Alive
Update Check Thread: Alive
None
Update Check Thread: Dead
Abilities Thread: Dead
Ability Thread: Alive
Update Check Thread: Alive
['Has a 33% chance of curing any major status ailment after each turn.']
Update Check Thread: Dead
Abilities Thread: Dead
Ability Thread: Alive
Update Check Thread: Alive
["Increases moves' accuracy to 1.3×.", 'Doubles damage inflicted with not-very-effective moves.']     
Update Check Thread: Dead
QThread: Destroyed while thread is still running

It crashes. I assume the "thread that is still running" was the ability thread as it didn't print that it was "dead".

To go into specifics of how the program works.

When starting the GUI the user is presented with a window where they can enter a name or number and press a button to retrieve information. When pressing the button the button clicked has the following code run:

#The "Mother Code" Run        
    def extract(self):
        self.pokemon = self.line.text().lower()
        Data.run_api(self,"pokemon", self.pokemon)
        pokecache.pokemon_dict.update(self.data)
        self.name = pokecache.pokemon_dict["name"].title()
        abilities.load_abilities(self)
        Data.check_if_load(self)

After running the api it starts running the abilities thread first:

#Thread
def load_abilities(self):
    global short_effects_updated
    short_effects_updated = False
    self.thread = QThread()
    self.worker = Worker()
    self.worker.moveToThread(self.thread)
    self.thread.started.connect(self.worker.abilities_data)
    
    
    self.worker.finished.connect(self.thread.quit)
    self.worker.finished.connect(self.worker.deleteLater)
    self.thread.started.connect(self.thread.deleteLater)

    self.worker.ab_data_pull.connect(ability_process)
    self.thread.start()
    
    self.thread.finished.connect(lambda:print("Abilities Thread: Dead"))

This code pulls all of the abilities information from the API. (To see the full code of this segment click here)

After that it runs the "check_if_load" thread which is as such:

#Thread
    def check_if_load(self):
        self.update_thread = QThread()
        self.update_worker = Worker()
        self.update_worker.moveToThread(self.update_thread)
        self.update_thread.started.connect(self.update_worker.all_data)
        
        self.update_worker.finished.connect(self.update_thread.quit)
        self.update_worker.finished.connect(self.update_worker.deleteLater)
        self.update_thread.started.connect(self.update_thread.deleteLater)
        
        self.update_worker.data_pull.connect(Data.update_check)
        self.update_thread.start()
        
        #Resets
        self.update_thread.finished.connect(lambda:self.skin_label.setPixmap(QPixmap(f"{start}{directory}pokedexbgnew2.png")))
        self.update_thread.finished.connect(lambda:self.borders_screen.setPixmap(QPixmap(f"{start}{directory}foreground.png")))
        self.update_thread.finished.connect(lambda:self.button_s.setEnabled(True))
        self.update_thread.finished.connect(lambda:print("Update Check Thread: Dead"))

The main part of this code is that it is connected to run "update_check" which is suppose to make specific changes after all the code is finished.

It's coded as such:

    def update_check(self):
        while not abilities.short_effects_updated:
            None
        abilities.short_effects_updated = print(abilities.short_effects)

Once the global flag in abilities no longer equals "None" it signals for update_check to run which prints the abilities.

Again this all works fine but it eventually crashes with the error: "QThread: Destroyed while thread is still running".

I'm wondering what I'm doing wrong and how I can fix it. Any help at all would be great! :)

[JonB]

@gunraidan
Here is the code (tested PyQt5) for the two possible approaches:

import json

from PyQt5 import QtCore

if __name__ == '__main__':
    # I put your sample JSON into a file, since they are not arriving at my serial port
    f = QtCore.QFile("file.json")
    if not f.open(QtCore.QIODevice.ReadOnly):
        raise "Whoops"
    # following line's `readAll()` returns `QByteArray` type, just like when you read from serial port
    qbytearray = f.readAll()
    f.close()

    # Use `json.loads()` approach:
    # next line converts Qt `QByteArray` type to Python `bytes` type...
    pythonbytearray = bytes(qbytearray)
    # ...so that now it is acceptable to `json.loads(...)`
    pokemon_dict = json.loads(pythonbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name']
    # next line prints `static`, which must be the value there
    print(x)

    # Use `QtCore.QJson...` approach:
    pokemon_dict = QtCore.QJsonDocument.fromJson(qbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name'].toString()
    # next line prints `static`, which must be the value there
    print(x)

As you can see, all you had to discover for Python/PyQt json.loads(...) is that you can convert a Qt QByteArray to a Python bytes array via bytes(qByteArrayValue).

Use either one of these approaches. The json modules is slightly better integrated into Python than the Qt QJson... classes (e.g. note the QJson expression requires the toString() at the end, but the json one does not), so you may prefer to use the former. On the other hand, while json.loads() requires converting a QByteArray to a bytes, QJsonDocument.fromJson() does not.

[SGaist]

Hi,

Aren't that many threads a bit overkill ?
Qt has QNetworkAccessManager to do API calls and it's asynchronous so it may fit the bill nicely without all the threads you seem to need.

[gunraidan]

@SGaist said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

Hi,

Aren't that many threads a bit overkill ?
Qt has QNetworkAccessManager to do API calls and it's asynchronous so it may fit the bill nicely without all the threads you seem to need.

I'm not family with it. Is there a good tutorial for it that uses Python?

[SGaist]

There are basic examples on the Python documentation of the class.

[gunraidan]

@SGaist said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

There are basic examples on the Python documentation of the class.

I managed to find more of a tutorial I had in mind.

I got the code to work on my end, but now I'm trying to get it to work in a PyQt GUI.

I can get the code to work in a GUI setting with the following:

from PyQt6 import QtNetwork
from PyQt6.QtCore import QUrl
import sys

from PyQt6.QtGui import*
from PyQt6 import QtWidgets
from PyQt6.QtWidgets import*

class MainWindow(QWidget):  
    def __init__ (self):
        super().__init__()
        self.title = "Window"
        self.left = 200
        self.top = 300
        self.width = 300
        self.height = 300
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top,self.width, self.height)
        self.site_request()
        self.start_button()
        self.show()
        
    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(self.site_request)
        
    
    def site_request(self):
        url = 'http://webcode.me'
        req = QtNetwork.QNetworkRequest(QUrl(url))
        
        self.nam = QtNetwork.QNetworkAccessManager()
        self.nam.finished.connect(self.handle_request)
        self.nam.get(req)
        
    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            
            bytes_string = reply.readAll()
            print(str(bytes_string, 'utf-8'))
        else:
            print ("Error")
            print(reply.errorString())
        

        
if __name__ == '__main__':        
    app = QApplication(sys.argv) 
    ex = MainWindow()        
    code = app.exec()
    sys.exit(code)

I decided to make the the QNetworkAccessManager into the following:

    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(GetData.site_request(self))
        

class GetData():
    def __init__(self):
        self.site_request()
    
    def site_request(self):

        url = 'http://webcode.me'
        req = QtNetwork.QNetworkRequest(QUrl(url))
        
        self.nam = QtNetwork.QNetworkAccessManager()
        self.nam.finished.connect(GetData.handle_request(self,url))
        self.nam.get(req)
        
    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            
            bytes_string = reply.readAll()
            print(str(bytes_string, 'utf-8'))
        else:
            print ("Error")
            print(reply.errorString())

When I run the code I get the following Traceback:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 37, in site_request
    self.nam = QtNetwork.QNetworkAccessManager()
AttributeError: 'bool' object has no attribute 'nam'
PS C:\Users\Nader\OneDrive\Documents\Coding\Python>  c:; cd 'c:\Users\Nader\OneDrive\Documents\Coding\Python'; & 'C:\Users\Nader\AppData\Local\Programs\Python\Python310\python.exe' 'c:\Users\Nader\.vscode\extensions\ms-python.python-2022.18.2\pythonFiles\lib\python\debugpy\adapter/../..\debugpy\launcher' '56993' '--' 'c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py' 
Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 56, in <module>
    ex = MainWindow()
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 19, in __init__
    self.start_button()
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 25, in start_button
    self.s_button.clicked.connect(GetData.site_request(self))
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 38, in site_request
    self.nam.finished.connect(GetData.handle_request(self,url))
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 42, in handle_request
    er = reply.error()
AttributeError: 'str' object has no attribute 'error'

I'm wondering what I'm doing wrong and how I can get the code functioning?

Also when I pull data from this api, while I get the data it starts off with this:
qt.tlsbackend.ossl: Failed to load libssl/libcrypto.

[JonB]

@gunraidan said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

self.nam = QtNetwork.QNetworkAccessManager()
AttributeError: 'bool' object has no attribute 'nam'

er = reply.error()
AttributeError: 'str' object has no attribute 'error'

These are both very strange errors to receive, hard to know what is going on from your code to cause.

I decided to make the the QNetworkAccessManager into the following:

I don't understand what this means, in what sense "make the QNetworkAccessManager" into anything?

self.nam.finished.connect(GetData.handle_request(self,url))

What is going on here? Where did you get an example of using such a construct for connect? If you just "invented" this yourself, it's wrong :) I would expect this to completely go wrong, goodness knows what the finished signal actually gets connected to after executing this line? At minimum I can see how/why this line would cause the

er = reply.error()
AttributeError: 'str' object has no attribute 'error'

Which is why the original self.nam.finished.connect(self.handle_request) works correctly but your change does not. Similarly with your change over to GetData.site_request(self). You have changed currently working code to something different for no apparent reason and then wonder why it does not work! :)

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

self.nam = QtNetwork.QNetworkAccessManager()
AttributeError: 'bool' object has no attribute 'nam'

er = reply.error()
AttributeError: 'str' object has no attribute 'error'

These are both very strange errors to receive, hard to know what is going on from your code to cause.

I decided to make the the QNetworkAccessManager into the following:

I don't understand what this means, in what sense "make the QNetworkAccessManager" into anything?

self.nam.finished.connect(GetData.handle_request(self,url))

What is going on here? Where did you get an example of using such a construct for connect? If you just "invented" this yourself, it's wrong :) I would expect this to completely go wrong, goodness knows what the finished signal actually gets connected to after executing this line? At minimum I can see how/why this line would cause the

er = reply.error()
AttributeError: 'str' object has no attribute 'error'

Which is why the original self.nam.finished.connect(self.handle_request) works correctly but your change does not. Similarly with your change over to GetData.site_request(self). You have changed currently working code to something different for no apparent reason and then wonder why it does not work! :)

The reason why I changed it is because when I simply put the code in a new class as such:

    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(self.site_request)
        

class GetData():
    def __init__(self):
        self.site_request()
    
    def site_request(self):

        url = 'http://webcode.me'
        req = QtNetwork.QNetworkRequest(QUrl(url))
        
        self.nam = QtNetwork.QNetworkAccessManager()
        self.nam.finished.connect(self.handle_request)
        self.nam.get(req)
        
    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            
            bytes_string = reply.readAll()
            print(str(bytes_string, 'utf-8'))
        else:
            print ("Error")
            print(reply.errorString())

I get the following Traceback:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 59, in <module>
    ex = MainWindow()        
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 22, in __init__
    self.start_button()
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 28, in start_button
    self.s_button.clicked.connect(self.site_request)
AttributeError: 'MainWindow' object has no attribute 'site_request'

When changing the button connect to the following:

    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(GetData.site_request)

Doing so starts the GUI but upon hitting the start button I get this Traceback:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 40, in site_request
    self.nam = QtNetwork.QNetworkAccessManager()
AttributeError: 'bool' object has no attribute 'nam'

Changing the button connect to GetData.site_request(self) results in this Traceback:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 59, in <module>
    ex = MainWindow()
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 22, in __init__
    self.start_button()
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 28, in start_button
    self.s_button.clicked.connect(GetData.site_request(self))
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 41, in site_request
    self.nam.finished.connect(self.handle_request)
AttributeError: 'MainWindow' object has no attribute 'handle_request'

So I decided to change self.nam.finished.connect(self.handle_request) to self.nam.finished.connect(GetData.handle_request(self)).

Running that I got the following error:

  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetworkClass.py", line 41, in site_request
    self.nam.finished.connect(GetData.handle_request(self))
TypeError: GetData.handle_request() missing 1 required positional argument: 'reply'

So I figured the reply variable needed the url to process as that's how it traditionally works when getting api in Python.

[JonB]

@gunraidan
Your attempts to introduce the GetData class, and the way you try to use GetData, are wrong. They might make some sense of you created a GetData instance. I don't know what you trying to achieve.

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan
Your attempts to introduce the GetData class, and the way you try to use GetData, are wrong. They might make some sense of you created a GetData instance. I don't know what you trying to achieve.

I'll just forget about it then.

I realize that I've been asking a lot in this thread, so I understand if I get ignored, but I do have a new issue that is very important and I can't figure out.

I want to pull information from this api page.

Traditional what I would do would create an api request get function:

    def run_api(self):
        contact = {'User-Agent': '("Accept: application/json", "Cache-Control: max-age=360",)'}
        response = requests.get ('https://pokeapi.co/api/v2/pokemon/pikachu'}', headers = contact)
        self.data = response.json()

I would then create a dictionary:
pokemon_dict = []

And then in the main function have the api get request save the information to the dictionary:

pokemon_dict.update(self.data)

Then I would print out something specific from the dictionary.
Such as pokemon_dict["abilities"] which would print all the information in abilities. Or something even more specific like pokemon_dict["abilities"][0]['ability']['name'] which would print the name of the first ability under abilities, which in this case the output of the code would print static.

When I try the same with the code when using QNetwork it doesn't really work.

For example take the code below:

from PyQt6 import QtNetwork
from PyQt6.QtCore import QUrl
import sys

from PyQt6.QtGui import*
from PyQt6 import QtWidgets
from PyQt6.QtWidgets import*

pokemon_dict = []

class MainWindow(QWidget):  
    def __init__ (self):
        super().__init__()
        self.title = "Window"
        self.left = 200
        self.top = 300
        self.width = 300
        self.height = 300
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top,self.width, self.height)

        self.start_button()
        self.show()
        
    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(self.site_request)
        
    
    def site_request(self):
        url = 'https://pokeapi.co/api/v2/pokemon/pikachu'
        req = QtNetwork.QNetworkRequest(QUrl(url))
        
        self.nam = QtNetwork.QNetworkAccessManager()
        self.nam.finished.connect(self.handle_request)
        self.nam.get(req)
        
    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            
            bytes_string = reply.readAll()
            pokemon_dict = bytes_string
            pokemon_dict.append(bytes_string)
            print(pokemon_dict)
        else:
            print ("Error")
            print(reply.errorString())
        

        
if __name__ == '__main__':        
    app = QApplication(sys.argv) 
    ex = MainWindow()        
    code = app.exec()
    sys.exit(code)

This successfully prints out everything in the api page as this is the output.

Interestingly, besides the qt.tlsbackend.ossl: Failed to load libssl/libcrypto. that people aren't sure what that is, it also starts the dictionary off with b', something that is not present in the original api link.

So doing something such as:

    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            
            bytes_string = reply.readAll()
            pokemon_dict = bytes_string
            pokemon_dict.append(bytes_string)
            print(pokemon_dict["abilities"])

Results in this output:

qt.tlsbackend.ossl: Failed to load libssl/libcrypto.
Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 47, in handle_request
    print(pokemon_dict["abilities"])
TypeError: QByteArray.__getitem__(): arguments did not match any overloaded call:
  overload 1: argument 1 has unexpected type 'str'
  overload 2: argument 1 has unexpected type 'str'

The same occurs when I do print(pokemon_dict["b"]) instead.

Entering print(pokemon_dict[0]) outputs b'{'. But changing the function to print(pokemon_dict["b'{'"]) results in the same previous Traceback.

I'm wondering what I am doing wrong? Any help at all would be greatly appreciated!

[JonB]

@gunraidan
I am guessing the reply is a JSON string? [https://pokeapi.co/api/v2/pokemon/25 : yes it is.] You need to parse it with a Python library or JSON Support in Qt.

pokemon_dict is an array of bytes (Python list), it's not a dictionary, you can't index that with a string hence the error message. Be aware that your code

            pokemon_dict = bytes_string
            pokemon_dict.append(bytes_string)

is it making it be two copies of the input bytes_string.

[gunraidan]

@JonB

Thank you for your response.

pokemon_dict = bytes_string was left in by accident.

I just want to be able to navigate through the api, the same or a similar way as using the traditional Python api method.

I don't see a template in the link you've provided, and possibly I'm just bad at Googling, but I can't really find anything online. Do you know of any simple templates I can find online? Or, if you could please, show me a quick mock up excerpt if that wouldn't be too much trouble?

[JonB]

@gunraidan
As I said, you are just missing one step. The bytes_string you get is just a string of the bytes/characters which arrive/come from file. You cannot access the "keys", like pokemon_dict["abilities"], until you have called some JSON library to parse that text as JSON, which is what it is.

For the JSON you have two choices: Qt has QJson... classes or Python has its own JSON library/classes. You might use either one.

For the Qt, untested but try:

from PyQt6 import QtCore

bytes_string = reply.readAll()
pokemon_dict = QtCore.QJsonDocument.fromJson(bytes_string)
# you may need next line, not sure:
# pokemon_dict = pokemon_dict.object()
print(pokemon_dict["abilities"])

Or you may prefer to do this with the Python JSON classes --- https://docs.python.org/3/library/json.html. I think that would be

import json

bytes_string = reply.readAll()
pokemon_dict = json.loads(bytes_string)
print(pokemon_dict["abilities"])

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan
As I said, you are just missing one step. The bytes_string you get is just a string of the bytes/characters which arrive/come from file. You cannot access the "keys", like pokemon_dict["abilities"], until you have called some JSON library to parse that text as JSON, which is what it is.

For the JSON you have two choices: Qt has QJson... classes or Python has its own JSON library/classes. You might use either one.

For the Qt, untested but try:

from PyQt6 import QtCore

bytes_string = reply.readAll()
pokemon_dict = QtCore.QJsonDocument.fromJson(bytes_string)
# you may need next line, not sure:
# pokemon_dict = pokemon_dict.object()
print(pokemon_dict["abilities"])

Or you may prefer to do this with the Python JSON classes --- https://docs.python.org/3/library/json.html. I think that would be

import json

bytes_string = reply.readAll()
pokemon_dict = json.loads(bytes_string)
print(pokemon_dict["abilities"])

Doing the first results in this error:

qt.tlsbackend.ossl: Failed to load libssl/libcrypto.
<PyQt6.QtCore.QJsonValue object at 0x00000182BF9CA570>

Doing the second results in this error:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 44, in handle_request
    pokemon_dict = json.loads(bytes_string)
  File "C:\Users\Nader\AppData\Local\Programs\Python\Python310\lib\json\__init__.py", line 339, in loads
    raise TypeError(f'the JSON object must be str, bytes or bytearray, '
TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

[JonB]

@gunraidan said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

Doing the first results in this error:

<PyQt6.QtCore.QJsonValue object at 0x00000182BF9CA570>

I don't see it being an error. ("qt.tlsbackend.ossl: Failed to load libssl/libcrypto." is over to you, you have had that from the start.) So that actually looks good I think, it has found a QJsonValue in pokemon_dict["abilities"], so it's working.

TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

Then you need to convert Qt QByteArray to bytes/bytearray, however you do that from PyQt6.

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

Doing the first results in this error:

<PyQt6.QtCore.QJsonValue object at 0x00000182BF9CA570>

I don't see it being an error. ("qt.tlsbackend.ossl: Failed to load libssl/libcrypto." is over to you, you have had that from the start.) So that actually looks good I think, it has found a QJsonValue in pokemon_dict["abilities"], so it's working.

TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

Then you need to convert Qt QByteArray to bytes/bytearray, however you do that from PyQt6.

When I type the following code:

    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            bytes_string = reply.readAll()
            pokemon_dict = QtCore.QJsonDocument.fromJson(bytes_string)
            pokemon_dict = pokemon_dict.object()
            print(pokemon_dict)

This is the output:

{'abilities': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A570>, 'base_experience': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A5E0>, 'forms': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A650>, 'game_indices': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A6C0>, 'height': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A730>, 'held_items': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A7A0>, 'id': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A810>, 'is_default': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A880>, 'location_area_encounters': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A8F0>, 'moves': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A960>, 'name': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0A9D0>, 'order': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AA40>, 'past_types': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AAB0>, 'species': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AB20>, 'sprites': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AB90>, 'stats': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AC00>, 'types': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0AC70>, 'weight': <PyQt6.QtCore.QJsonValue object at 0x000001EC6DE0ACE0>}

So it does successfully import the data. However, unlike the keys, the values in the dictionary aren't strings but more so strange code. Is there a way to have the values be the same text string found in the api like the keys?

[JonB]

@gunraidan
You have to read the Qt QJson... classes documentation and write the code. Btw did you try to see if your pokemon_dict["abilities"][0]['ability']['name'] works?

From Python you might be more comfortable getting the json module working. It may integrate more smoothly in Python than the Qt one, if the Qt one doesn't work with your pokemon_dict["abilities"][0]['ability']['name'].

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan
You have to read the Qt QJson... classes documentation and write the code. Btw did you try to see if your pokemon_dict["abilities"][0]['ability']['name'] works?

From Python you might be more comfortable getting the json module working. It may integrate more smoothly in Python than the Qt one, if the Qt one doesn't work with your pokemon_dict["abilities"][0]['ability']['name'].

This is embarrassing but I just realized I quoted you before without putting my code in.
It strongly gives the impression I'm not putting in the effort, which I don't think is accurate.

I came up with the following code:

    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:

            bytes_string = reply.readAll()
            pokemon_dict = json.loads(bytes_string)
            x = QByteArray(pokemon_dict["abilities"][0]['ability']['name'])
            print(x)

In my head the json.loads will load the response into json format and then x will result in that part of the code being transferred to bytes so Python can read it.

However, I still get the same error:

Traceback (most recent call last):
  File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 44, in handle_request
    bytes_string = json.loads(reply.readAll())
  File "C:\Users\Nader\AppData\Local\Programs\Python\Python310\lib\json\__init__.py", line 339, in loads
    raise TypeError(f'the JSON object must be str, bytes or bytearray, '
TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

I have gone to the documentation here, but it lists simply the function and no examples of QJson in use (outside of a saved game load which isn't much like I'm doing.)

[JonB]

@gunraidan said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

I have gone to the documentation here, but it lists simply the function and no examples of QJson in use (outside of a saved game load which isn't much like I'm doing.)

Well, that's all you get!

You have attempted to change your code in the light of the error, but unfortunately not the right thing! Please read the message carefully. First:

File "c:\Users\Nader\OneDrive\Documents\Coding\Python\TestNetwork.py", line 44, in handle_request

bytes_string = json.loads(reply.readAll())

Since that clearly shows bytes_string = json.loads(reply.readAll()) while you claim your code has pokemon_dict = json.loads(bytes_string), how can you get that error message from the code you show? I can only conclude that is not the code you have to cause that message. Please don't do this, it makes it very frustrating when people try to help and code/messages are not actually what you claim they are.

Second:

File "C:\Users\Nader\AppData\Local\Programs\Python\Python310\lib\json_init_.py", line 339, in loads

raise TypeError(f'the JSON object must be str, bytes or bytearray, '

TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

Read the error message. It tells you it was in the json.loads(something) call. It tells you it requires the parameter to be "str, bytes or bytearray", but that it is actually "QByteArray" (as returned from readAll()). And it is apparently not prepared to convert for you. Hence I wrote earlier:

TypeError: the JSON object must be str, bytes or bytearray, not QByteArray

Then you need to convert Qt QByteArray to bytes/bytearray, however you do that from PyQt6.

You were supposed to Google to find out how to do that. I don't, I don't use Python. Your putting in x = QByteArray(...) after the json.loads() call is not going to address this, you need to change what you pass to json.loads().

I will have a go at producing something in next post.....

[JonB]

@gunraidan
Here is the code (tested PyQt5) for the two possible approaches:

import json

from PyQt5 import QtCore

if __name__ == '__main__':
    # I put your sample JSON into a file, since they are not arriving at my serial port
    f = QtCore.QFile("file.json")
    if not f.open(QtCore.QIODevice.ReadOnly):
        raise "Whoops"
    # following line's `readAll()` returns `QByteArray` type, just like when you read from serial port
    qbytearray = f.readAll()
    f.close()

    # Use `json.loads()` approach:
    # next line converts Qt `QByteArray` type to Python `bytes` type...
    pythonbytearray = bytes(qbytearray)
    # ...so that now it is acceptable to `json.loads(...)`
    pokemon_dict = json.loads(pythonbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name']
    # next line prints `static`, which must be the value there
    print(x)

    # Use `QtCore.QJson...` approach:
    pokemon_dict = QtCore.QJsonDocument.fromJson(qbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name'].toString()
    # next line prints `static`, which must be the value there
    print(x)

As you can see, all you had to discover for Python/PyQt json.loads(...) is that you can convert a Qt QByteArray to a Python bytes array via bytes(qByteArrayValue).

Use either one of these approaches. The json modules is slightly better integrated into Python than the Qt QJson... classes (e.g. note the QJson expression requires the toString() at the end, but the json one does not), so you may prefer to use the former. On the other hand, while json.loads() requires converting a QByteArray to a bytes, QJsonDocument.fromJson() does not.

[gunraidan]

@JonB said in Occasionally get "QThread: Destroyed while thread is still running" when running multiple threads:

@gunraidan
Here is the code (tested PyQt5) for the two possible approaches:

import json

from PyQt5 import QtCore

if __name__ == '__main__':
    # I put your sample JSON into a file, since they are not arriving at my serial port
    f = QtCore.QFile("file.json")
    if not f.open(QtCore.QIODevice.ReadOnly):
        raise "Whoops"
    # following line's `readAll()` returns `QByteArray` type, just like when you read from serial port
    qbytearray = f.readAll()
    f.close()

    # Use `json.loads()` approach:
    # next line converts Qt `QByteArray` type to Python `bytes` type...
    pythonbytearray = bytes(qbytearray)
    # ...so that now it is acceptable to `json.loads(...)`
    pokemon_dict = json.loads(pythonbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name']
    # next line prints `static`, which must be the value there
    print(x)

    # Use `QtCore.QJson...` approach:
    pokemon_dict = QtCore.QJsonDocument.fromJson(qbytearray)
    x = pokemon_dict["abilities"][0]['ability']['name'].toString()
    # next line prints `static`, which must be the value there
    print(x)

As you can see, all you had to discover for Python/PyQt json.loads(...) is that you can convert a Qt QByteArray to a Python bytes array via bytes(qByteArrayValue).

Use either one of these approaches. The json modules is slightly better integrated into Python than the Qt QJson... classes (e.g. note the QJson expression requires the toString() at the end, but the json one does not), so you may prefer to use the former. On the other hand, while json.loads() requires converting a QByteArray to a bytes, QJsonDocument.fromJson() does not.

Thank you.

The following code:

pokemon_dict = []
json2qt = QtCore.QJsonDocument.fromJson

class MainWindow(QWidget):  
    def __init__ (self):
        super().__init__()
        self.title = "Window"
        self.left = 200
        self.top = 300
        self.width = 300
        self.height = 300
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top,self.width, self.height)

        self.start_button()
        self.show()
        
    def start_button(self):
        self.s_button = QtWidgets.QPushButton(self)
        self.s_button.setText('Start')
        self.s_button.clicked.connect(self.site_request)
        
    
    def site_request(self):
        url = 'https://pokeapi.co/api/v2/pokemon/pikachu'
        req = QtNetwork.QNetworkRequest(QUrl(url))
        
        self.nam = QtNetwork.QNetworkAccessManager()
        self.nam.finished.connect(self.handle_request)
        self.nam.get(req)
        
    def handle_request(self, reply):
        er = reply.error()
        
        if er == QtNetwork.QNetworkReply.NetworkError.NoError:
            qbyte = reply.readAll()
            pokemon_dict = json2qt(qbyte)
            x = pokemon_dict["abilities"][0]['ability']['name'].toString()
            print(x)
        else:
            print ("Error")
            print(reply.errorString())
        
        
if __name__ == '__main__':        
    app = QApplication(sys.argv) 
    ex = MainWindow()        
    code = app.exec()
    sys.exit(code)

Works as it prints the name: "static".

Thank you for all your help!

One more thing, that you don't have to answer. Do you have any idea what the qt.tlsbackend.ossl: Failed to load libssl/libcrypto. could be? It doesn't effect the program at all and I assume has to do with the api's security not being picked up since it references "ssl"?

Doing some research of what "libssl and libcrypto are took me to this page.