Real Time data and Json File

[deleted286]

Hi everyone. I want to ask something.
I have a project that should be drawing chart which includes the telemetry datas.
The datas will come to me real time.
Firstly, im keeping them in a json file, and then read this telemetry datas from json.
I add them in a table widget, and choose which data am i want and create a chart with that selected ones.

Im confusing is there any way to keep them in a json. Or is this a very bad idea which i'm trying to do?
If it necessary i can share my code for check on

[Christian Ehrlicher]

@suslucoder said in Real Time data and Json File:

The datas will come to me real time.

This does not help at all - the data rate is important. Not some undefined requirement word like 'real time'.
And no - storing data in json is not fast.

[deleted286]

@Christian-Ehrlicher Actually, im trying to create a config file which is the type of json.
Datas coming from autopilot and all i know is, im receiving about 600 packet of data

[Christian Ehrlicher]

First you said you're getting data from somewhere and store it as json, now you read about a config file... can you please first think before you write something?

[deleted286]

@Christian-Ehrlicher
Im storing it as json it is true. But my aim create a file like configuration file

[jsulm]

@suslucoder Why would you store data in a configuration file?!

[JKSH]

@suslucoder said in Real Time data and Json File:

The datas will come to me real time.
Firstly, im keeping them in a json file, and then read this telemetry datas from json.
I add them in a table widget, and choose which data am i want and create a chart with that selected ones.
Im confusing is there any way to keep them in a json. Or is this a very bad idea which i'm trying to do?

It is a bad idea to store chartable data in a JSON file. A database (like an SQLite file, for example) is far more suitable.

[deleted286]

@jsulm yeah, i dont know why im storing datas in json as a config file, my boss wants and i do thats all

[deleted286]

@JKSH thank you, but is there anything wrong which i do as i explain

[JKSH]

@suslucoder said in Real Time data and Json File:

is there anything wrong

Yes, there are problems. Every time new data packets arrive, you must rewrite the whole JSON file.

You won't notice anything wrong when the file is small. But as the file gets bigger, performance will become very bad, and you will wear out your hard drive/SSD faster. The risk of data corruption might also be higher.

my boss wants

I can't understand why your boss wants this.

[deleted286]

@JKSH he thinks that keeping datas on json == creating a config file. Like settings folder. But i know it isnt, so i dont know how can i handle with that issue

[jsulm]

@suslucoder said in Real Time data and Json File:

so i dont know how can i handle with that issue

You could explain to him the disadvantages shown by @JKSH

[deleted286]

@jsulm thank you

[J.Hilk]

@suslucoder well, you could only save the data as a json file, on program close, or something similar.

Fits your requirement and he will never know that the actual data processing/storage is something different.

Doesn't hurt to have redundancies either.

[JKSH]

@J-Hilk said in Real Time data and Json File:

you could only save the data as a json file, on program close, or something similar.

Good idea; this helps avoid the performance issues and hard drive wearing. Beware though: If the program crashes, all of the data will be lost.

[deleted286]

@JKSH i spoke with him, he says he wants a config file with json.

It should include the name of the data, and the type. Like
Name: string
Age: int
Height:float etc.

I dont know how to create such a file

[JonB]

@J-Hilk

and he will never know that the actual data processing/storage is something different.

ROFL. Are you now advising Qt programmers to deceive their bosses? ;-)

@suslucoder

I dont know how to create such a file

What don't you know how to do? You have done JSON stuff, haven't you, so what is different about this task?

[KroMignon]

@suslucoder said in Real Time data and Json File:

I dont know how to create such a file

Have you tried to read JSON documentation?
==> https://doc.qt.io/qt-5/json.html
==> https://doc.qt.io/qt-5/qtcore-serialization-savegame-example.html

[J.Hilk]

@JonB said in Real Time data and Json File:

ROFL. Are you now advising Qt programmers to deceive their bosses? ;-)

😱 me, never!

The boss will get what he want's, in the end. Bosses always only care about the end result 🤷‍♂️

[deleted286]

@J-Hilk ahahahha you made me laugh so much

I create the file, but i dont know how to read such a complex json :D
Can anybody help?

   {
"GPS": [
    {

        "GPS ID": ["integer", "0"],
        "GPS Mod": ["integer", "1"],
        "GPS Utc": ["float", "2"],
        "GPS Latitude": ["float", "3"],
        "GPS Longitude": ["float", "4"],
        "GPS Alt":  ["float", "5"],
        "GPS Yer Hızı":  ["float", "6"],
        "GPS Dikey Hız":["float", "7"],
        "GPS Yatay Doğruluk":  ["float", "8"],
        "GPS Dikey Doğruluk": ["float", "9"],
        "GPS Yer Başı":  ["float", "10"],
        "GPS Hdop": ["float", "11"],
        "GPS Vdop": ["float", "12"],
        "GPS Uydu Sayısı": ["integer", "13"],
        "GPS Boy":  ["integer", "14"]
    } 
  ],


"Imu": [
 {
     
    "HW ID": ["integer", "0"],
        "HW Motor": ["float", "1"],
        "HW Motor1": ["float", "2"],
        "HW Motor2": ["float", "3"],
        "HW Motor3": ["float", "4"],
        "HW Motor4": ["float", "5"],
        "HW P": ["float", "6"],
        "HW R": ["float", "7"],
        "HW Y": ["float", "8"],
        "HW Boy": ["float", "9"]
       }
   ]
     }