CODEWITHSUNDEEP
pythonjson
user1099053
user1099053

Reputation:

json.loads formatting issue

I'm currently learning the basics behind Python. I've been tasked with creating a few simple database-related Python scripts. I'm having an issue working with JSON on my SELECT script.

The data format I need is as follows;

{
    "Data": {
        "name1": "val1",
        "name2": "val2",
        "name3": "val3",
        "name4": "val4"
    },
    "IMPORTANT_NOTE": "This data is from the test database - used for demonstration only!"
}

The data itself is stored as JSON within the DB so it's 1 field. The data is retrieves as follows;

  try:
    db = MySQLdb.connect(dbhost, dbuser, dbpass, sqldb)
  except:
    msg = "Connect error"
  else:
    cursor = db.cursor()
    sql = "SELECT JSON_DATA FROM TEST_DB_TABLE WHERE DATA_GUID= %s"
    args = "TestData"
    cursor.execute(sql,args)
    for row in curosr.fetchall() : jsondata = row[0]
  finally:
    db.close()

This returns the following if i print(jsondata);

{
  "name1": "val1",
  "name2": "val2",
  "name3": "val3",
  "name4": "val4"
}

I'm used to PHP so I'd expect to use an array to form the rest of the data and finalize it with json_encode. I understand that Python's equivalents to arrays are dictionaries so I feel like that's what I should use here. I did try this at the end;

  data = json.loads(jsondata)
  FinOut = {"Data": data, "IMPORTANT_NOTE": "This data is from the test database - used for demonstration only!"
  print(FinOut)

... The issue here is that it returns invalid JSON;

{'Data': {u'name1': u'val1', u'name2': u'val2', u'name3': u'val3', u'name4': u'val4'}, 'IMPORTANT_NOTE': 'This data is from the test database - used for demonstration only!'}

I did try json.load(jsondata) instead but then cgitb reports an error (I assume because .load is a file-based equivalent;

<type 'exceptions.AttributeError'>: 'str' object has no attribute 'read' 
      args = ("'str' object has no attribute 'read'",) 
      message = "'str' object has no attribute 'read'"

Any ideas on how I correct this to output the data in a format similar to the one at the top?

Upvotes: 0

Views: 1126

Answers (1)

Daniel Roseman
Daniel Roseman

Reputation: 599490

You converted your JSON object to a Python dict. Why are you expecting a dict to be valid JSON? It's not. If you want JSON, you should convert your dict back into that format:

json_data = json.dumps(FinOut)

Upvotes: 2

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