GSM.decode strange result

SummerSeaSun commented 2 years ago

Hi, I've tried with python3.10 but you can see that Out[4 ] is pretty strange as result, any idea on how to fix this?

In [1]: from smspdudecoder.codecs import GSM, UCS2

In [2]: GSM.decode(GSM.encode('1234567', with_padding=True), strip_padding=True)
Out[2]: '1234567'

In [4]: GSM.decode('07919333851805420406D0D4641300002220720171424087C7B29B9E6697416376BAECA69759206AB2099A068D45D0B52804D1E561D00D744EBFE5EE34081
   ...: E9ECFCBF23F280C8287CFE176D94D7F83C66F37A8EE068DC3EEB7BB0C22A741F3373B', strip_padding=True)
Out[4]: 'ì"NÆSΔF$BòΣ@MΞYÇ@@ò£".¡8B@æ<,v&Of.ùΞfN.v&/f$"MlèΞ\r4,è:-Λè"Ψåù:¥:NüΠwNù$åßÉ/Πàì\nù$å>Ån.v&àùΞüvù*wùΞÅvüv.ù"NùΞàf'

I've tried out also python-messaging that output an expected readable result of Out[4]:

In [1]: from messaging.sms import  SmsDeliver

In [2]: pdutext='07919333851805420406D0D4641300002220720171424087C7B29B9E6697416376BAECA69759206AB2099A068D45D0B52804D1E561D00D744EBFE5EE34081E9ECFCBF23F280C8287CFE176D
   ...: 94D7F83C66F37A8EE068DC3EEB7BB0C22A741F3373B'

In [3]: x=SmsDeliver(pdutext)

In [4]: x.text
Out[4]: 'Gentile cliente, TIM SAFE WEB tra 7 giorni passerà a pagamento con un canone di sol'

alexpirine commented 2 years ago

Hello,

GSM and UCS2 are string codecs, just like ASCII, ISO-885-1, UTF-8, and so on.

So they are only relevant to encode and decode text.

The payload you are providing seems to be an SMS Deliver PDU - it's a binary payload containing various fields describing an incoming SMS message, text content being just one of them.

This library does not have a very good high level API to decode PDUs yet, but there is a shortcut available that you can use:

>>> from smspdudecoder.easy import *
>>> easy_sms('07919333851805420406D0D4641300002220720171424087C7B29B9E6697416376BAECA69759206AB2099A068D45D0B52804D1E561D00D744EBFE5EE34081E9ECFCBF23F280C8287CFE176D94D7F83C66F37A8EE068DC3EEB7BB0C22A741F3373B')
{
  'sender': 'TIM',
  'date': datetime.datetime(2022, 2, 27, 9, 17, 24, tzinfo=datetime.timezone.utc),
  'content': 'Gentile cliente, TIM SAFE WEB tra 7 giorni passerà a pagamento con un canone di sol',
  'partial': False,
}

alexpirine commented 2 years ago

Feel free to re-open if you have other questions, @SummerSeaSun

qotto / smspdudecoder

GSM.decode strange result #8