What value is missing in my JSON parse?

Processing Coding Questions
1

I’m working on building two programs, one in Python and one in Processing, to communicate over socket TCP / data stream.

75% is working perfectly:

  • Encoding JSON and sending over socket from Processing
  • Receiving message and decoding JSON in Python
  • Encoding JSON and sending over socket from Python

What is giving me trouble is parseJSONObject() in Processing:

reference: parseJSONObject()

Python originally builds the following string:

Python

msgPayload = {}
msgPayload['dataReq'] = True
msgPayload['captureCount'] = commHandler.imageCaptureCount
msgPayload['flatHash'] = commHandler.hashFlat
msgPayload['tbBlue'] = commHandler.tbDialogue
msgPayload['tbGrey'] = commHandler.tbGrey
msgPayload['tbFight'] = commHandler.tbFight

jsonObj = jsonpickle.encode(msgPayload)
jsonDumpStr = jsonpickle.dumps(jsonObj)

print(jsonDumpStr)

"{\"dataReq\": true, \"captureCount\": 0, \"flatHash\": false, \"tbBlue\": false, \"tbGrey\": false, \"tbFight\": false}"

However, attempting parseJSONObject() on the received string failed because:

Processing

"{\"dataReq\": true, \"captureCount\": 0, \"flatHash\": false, \"tbBlue\": false, \"tbGrey\": false, \"tbFight\": false}"
java.lang.RuntimeException: A JSONObject text must begin with '{'

So, I trimmed the string in python to remove the quotes from the encoded bytes:

Python

jsonDumpStrTrimmed = jsonDumpStr[1:(len(jsonDumpStr)-1)]
jsonDumpBytes = jsonDumpStr.encode('UTF-8')

This still results in a failed pasreJSONObject() in Processing because:

Processing

if (myClient.available() > 0) { 
  raw = myClient.readString();
  print(raw);
    
  JSONObject json = parseJSONObject(raw);

{\"dataReq\": true, \"captureCount\": 0, \"flatHash\": false, \"tbBlue\": false, \"tbGrey\": false, \"tbFight\": false}
java.lang.RuntimeException: Missing value

I must be missing something reaaaally fundamental because I don’t see any missing values or foobar JSON encoding. Help?

2

My buddy and I found the root cause. jsonPickle.encode() and .dumps are essentially the same thing, so I was encoding my data twice. I removed the encode() function in Python and Processing can parse successfully.

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