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8518 :: Continuous use of parseJson causes software crash

• nnahito (orginal) [2021-10-20T07:18:39+02:00] view original

  I'm using a library called wNim to create GUI software.
  It is a chat client in Nim that uses WebSocket.
  The server sends the data in JSON.
  So I am using parseJson to parse JSON.
  However, when I run the software, the software suddenly crashes.
  At first I couldn't figure out the cause and was looking for a place to crash in print debugging.
  Then it seemed to be running parseJson and crashing the software.
  Try except did not stop the crash.
  I did a search and found that parseJson was slow, which I thought was likely the cause.
  https://github.com/nim-lang/Nim/issues/12152
  I decided to use packedjson because it seemed to be a good choice.
  https://github.com/Araq/packedjson
  Crashes are less frequent, but still occur on rare occasions.
  I have the following two questions.
  

  1. Why does it crash without showing any errors?

  
  

  2. Is there a library that is faster than packedjson?

  
  Please let me know if you know of anyone who can help.
  Thank you.
  

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• jasonfi (orginal) [2021-10-20T08:12:29+02:00] view original

  Your diagnosis of the problem doesn't sound right. Why would your program crash just because of a slow component? What you should do is mock your calls to parseJson so that it always returns a static JsonNode containing test values. This would confirm that parsing JSON is the cause if the crashes stop.

  It also sounds like you need more granular tests as well, to confirm that each component works as expected in isolation.

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• Araq (orginal) [2021-10-20T11:14:00+02:00] view original

  It's much more likely the crash comes from wNim than from our JSON components, no offense to wNim implied.

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• nnahito (orginal) [2021-10-20T12:14:08+02:00] view original

  Thank you for your reply. I now understand that parseJson is unlikely to be the source of the crash.

  I feel very sorry that I cannot present the source code.

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• ynfle (orginal) [2021-10-20T13:28:28+02:00] view original

  Try jsony

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• nnahito (orginal) [2021-10-20T16:57:15+02:00] view original

  Thank you! I'll try it

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