user_ctrl.py 文件源码

def addClassCodeToStudent(email, classCode, dynamoDBInstance):
  userTable = dbUtils.getTable('users', dynamoDBInstance)
  if userTable:
    codeSet = set([classCode])
    addClassToUser = {
      'Key': {'email': email},
      'UpdateExpression': 'ADD classCodes :i',
      'ExpressionAttributeValues': { ':i': codeSet },
      'ReturnValues' : 'UPDATED_NEW'
    }
    res = dbUtils.updateItem(addClassToUser, userTable)
    if (  res and
          'Attributes' in res and
          'classCodes' in res['Attributes'] and
          classCode in res['Attributes']['classCodes']
    ):
      return res['Attributes']['classCodes']
  return None