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pickleDB in Python help
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MathBoy1 (0)

For a Course Site (created using flask), I have created a json database which I am accessing using pickleDB in main.py.

Here is how my course.json looks like:

    {
      "Course A": 
      {"Student1": 
      {
        "grade":"",
        "distribution":"",
        "timezone":"",
        "rank":"",
      },
      "Student2":
      {
        "grade":"",
        "distribution":"",
        "timezone":"",
        "rank":"",
      }
      },
      
      "Course B": 
      {"Student1": 
      {
        "grade":"",
        "distribution":"",
        "timezone":"",
        "rank":"",
      },
      "Student2":
      {
        "grade":"",
        "distribution":"",
        "timezone":"",
        "rank":"",
      }
      }
    }

I've added all necessary imports and set it up fine.
Now, from a form, I requested the data (for a new student), and I want to add it to course A, and I've used the append feature of pickleDB like this:

      course.append(courseName, 
      {username: 
      {
        "grade":userGrade,
        "distribution":userDistribution,
        "timezone":userTimezone,
        "rank":userRank,
      }
      }
    	)

however, when I do so, an error throws up. Here's the error:

    [2021-06-17 08:59:08,203] ERROR in app: Exception on /admin/assign [POST]
    Traceback (most recent call last):
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/app.py", line 2447, in wsgi_app
        response = self.full_dispatch_request()
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/app.py", line 1952, in full_dispatch_request
        rv = self.handle_user_exception(e)
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/app.py", line 1821, in handle_user_exception
        reraise(exc_type, exc_value, tb)
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise
        raise value
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/app.py", line 1950, in full_dispatch_request
        rv = self.dispatch_request()
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/flask/app.py", line 1936, in dispatch_request
        return self.view_functions[rule.endpoint](**req.view_args)
      File "main.py", line 398, in courseAdd
        course.append(courseName,
      File "/opt/virtualenvs/python3/lib/python3.8/site-packages/pickledb.py", line 151, in append
        self.db[key] = tmp + more
    TypeError: unsupported operand type(s) for +: 'dict' and 'dict'

I don't know why i am getting the error, and I referred to pickleDB docs too: https://patx.github.io/pickledb/commands.html

Comments
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MathBoy1 (0)

Could I have any help with this?

InvisibleOne (3227)

The error is because you are trying to add tmp + more which you cannot do since they are both dictionaries, or at least that's what the error is saying.

MathBoy1 (0)

@InvisibleOne How could I do it without getting the error?

MathBoy1 (0)

@InvisibleOne Had any luck figuring out the issue?