def display_difference():
'''
Given a number through GET, returns json with following attrs:
- number: the number given through GET
- value: calculated value from number (see models.NumberRecord)
- last_requested: datetime in isoformat of when record is updated
- occurences: number of times this number has been queried
If any errors occur, a JSON with the following content will return:
- message: explanation of error
- code: associated error code
'''
try:
number = int(request.args.get('number'))
except (TypeError, ValueError):
return jsonify(**{
'message': 'Please provide a number',
'code': ErrorCode.NO_NUMBER
}
)
if not (1 <= number <= 100):
return jsonify(**{
'message': 'Number must be in the range of 1 to 100',
'code': ErrorCode.OUT_OF_RANGE
}
)
record = db.session.query(NumberRecord).filter(
NumberRecord.number==number).first()
if not record:
record = NumberRecord(number=number, occurences=0)
record.set_value()
db.session.add(record)
record.last_requested = datetime.datetime.now()
record.occurences += 1
# This feels dirty
# Would be better to incorporate something like ZopeTransactionManager...
db.session.commit()
return jsonify(**record.to_json())
