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Va debugger ton
par
Stéphane Wirtel
PyCon FR 2017 - Toulouse - 23/09/2017
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Salut, je suis Stéphane
par ma fille
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Qui aime developper... ?
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Debugger c'est Hard!
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Que fait ce code ?
# Example 1
def main():
for i in range(1, 4):
i /= 4
if i == 4:
print('Salut PyConFR 2017')
if __name__ == '__main__':
main()
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Slide 6
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Que fait ce code ?
# Example 1
def main():
for i in range(1, 4):
i /= 4
if i == 4:
print('Salut PyConFR 2017')
if __name__ == '__main__':
main()
$ python example1.py
$
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Slide 7
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La sacro-sainte fonction print()
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Slide 8
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La sacro-sainte fonction print()
# Example 2
def main():
for i in range(1, 4):
i /= 4
print(i)
if i == 4:
print('Salut PyConFR 2017')
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Slide 9
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La sacro-sainte fonction print()
# Example 2
def main():
for i in range(1, 4):
i /= 4
print(i)
if i == 4:
print('Salut PyConFR 2017')
$ python example2.py
0
0
0
$
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Le module logging
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Utilisons logging
# Example 3
import logging
def main():
logging.basicConfig(level=logging.INFO)
logging.info('start program')
logging.debug("before loop")
for i in range(1, 4):
i /= 4
logging.debug(i)
logging.debug("after loop")
if i == 4:
print("Hello PyConFR 2017")
logging.debug("Hello PyConFR 2017")
logging.info('end program')
if __name__ == '__main__':
main()
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Utilisons logging
# Example 3
import logging
def main():
logging.basicConfig(level=logging.INFO)
logging.info('start program')
logging.debug("before loop")
for i in range(1, 4):
i /= 4
logging.debug(i)
logging.debug("after loop")
if i == 4:
print("Hello PyConFR 2017")
logging.debug("Hello PyConFR 2017")
logging.info('end program')
if __name__ == '__main__':
main()
INFO:root:start program
INFO:root:end program
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Utilisons logging
# Example 4
import logging
def main():
logging.basicConfig(level=logging.DEBUG)
logging.info('start program')
logging.debug("before loop")
for i in range(1, 4):
i /= 4
logging.debug(i)
logging.debug("after loop")
if i == 4:
print("Hello PyConFR 2017")
logging.debug("Hello PyConFR 2017")
logging.info('end program')
if __name__ == '__main__':
main()
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Utilisons logging
INFO:root:start program
DEBUG:root:before loop
DEBUG:root:0
DEBUG:root:0
DEBUG:root:0
DEBUG:root:after loop
INFO:root:end program
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Utilisons logging
INFO:root:start program
DEBUG:root:before loop
DEBUG:root:0
DEBUG:root:0
DEBUG:root:0
DEBUG:root:after loop
INFO:root:end program
Obligé de modifier le niveau de log pour voir ce qu'il se passe.
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Cool
mais
Modification du code
Execution
Oubli de supprimer le print en production...
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que faire, quoi utiliser...
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Un debugger!
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PDB
Python Debugger est l'outil natif pour aider les développeurs à trouver et
corriger les bugs de leur logiciel fétiche (ou celui que l'on récupère d'un ancien
collègue ou prestataire...)
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Eh oui, Python vient avec un debugger!
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Comment faire
import pdb; pdb.set_trace()
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Comment faire
import pdb; pdb.set_trace()
# Example 5
import pdb
def main():
for i in range(1, 4):
i /= 4
if i == 4:
print("Hello PyConFR 2017")
if __name__ == '__main__':
pdb.set_trace()
main()
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Comment faire
import pdb; pdb.set_trace()
# Example 5
import pdb
def main():
for i in range(1, 4):
i /= 4
if i == 4:
print("Hello PyConFR 2017")
if __name__ == '__main__':
pdb.set_trace()
main()
$ python example5.py
> example5.py(7)main()
-> for i in range(1, 4):
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Comment faire
Example 6
import pdb
def do_something():
raise Exception("bug")
def main():
try:
do_something()
except Exception:
pdb.post_mortem()
if __name__ == '__main__':
main()
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Comment faire
Example 6
import pdb
def do_something():
raise Exception("bug")
def main():
try:
do_something()
except Exception:
pdb.post_mortem()
if __name__ == '__main__':
main()
> example6.py(4)do_something()
-> raise Exception("bug")
(Pdb) bt
example6.py(8)main()
-> do_something()
> example6.py(4)do_something()
-> raise Exception("bug")
(Pdb) ll
3 def do_something():
4 -> raise Exception("bug")
(Pdb)
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Comment faire
On peut aussi charger pdb comme un module à la ligne de commande.
$ python -m pdb
$ python -m pdb -c "command"
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Slide 27
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Prenons un exemple lisant un .csv
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Prenons un exemple lisant un .csv
import pendulum
import csv
class Event:
def __init__(self, name, date):
self.name = name
self.date = pendulum.parse(date)
def get_events(stream):
for row in csv.reader(stream):
yield Event(*row)
def main():
with open('events.csv') as stream:
for event in get_events(stream):
print(event.name, event.date)
if __name__ == '__main__':
main()
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Prenons un exemple lisant un .csv
import pendulum
import csv
class Event:
def __init__(self, name, date):
self.name = name
self.date = pendulum.parse(date)
def get_events(stream):
for row in csv.reader(stream):
yield Event(*row)
def main():
with open('events.csv') as stream:
for event in get_events(stream):
print(event.name, event.date)
if __name__ == '__main__':
main()
PyCon France,2017-09-21
PyCon Canada,2017-11-18
PyCon US,2017-05-17
Python FOSDEM,2018-02-03
Python TOTO,x
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Prenons un exemple lisant un .csv
$ python events.py
Non d'un petit Python, CRASH avec deux exceptions :/
PyCon France 2017-09-21T00:00:00+00:00
PyCon Canada 2017-11-18T00:00:00+00:00
PyCon US 2017-05-17T00:00:00+00:00
Python FOSDEM 2018-02-03T00:00:00+00:00
File "/home/stephane/.virtualenvs/flask/lib/python3.6/site-packages/dateutil/par
raise ValueError("Unknown string format")
ValueError: Unknown string format
During handling of the above exception, another exception occurred:
File "/home/stephane/.virtualenvs/flask/lib/python3.6/site-packages/pendulum/par
raise ParserError('Invalid date string: {}'.format(text))
pendulum.parsing.exceptions.ParserError: Invalid date string: x
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Je débugge
$ python -m pdb events.py
> events.py(1)()
-> import pendulum
(Pdb)
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Je liste mon code avec l ou ll
(Pdb) ll
1 -> import pendulum
2 import csv
3
4 class Event:
5 def __init__(self, name, date):
6 self.name = name
7 self.date = pendulum.parse(date)
8
9 def get_events(stream):
10 for row in csv.reader(stream):
11 yield Event(*row)
12
13 def main():
14 with open('events.csv') as stream:
15 for event in get_events(stream):
16 print(event.name, event.date)
17
18 if __name__ == '__main__':
19 main()
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J'avance d'une ligne
(Pdb) next
> events.py(2)()
-> import csv
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J'avance d'une ligne
(Pdb) next
> events.py(2)()
-> import csv
(Pdb) ll
1 import pendulum
2 -> import csv
3
4 class Event:
5 def __init__(self, name, date):
6 self.name = name
7 self.date = pendulum.parse(date)
8
9 def get_events(stream):
10 for row in csv.reader(stream):
11 yield Event(*row)
12
13 def main():
14 with open('events.csv') as stream:
15 for event in get_events(stream):
16 print(event.name, event.date)
17
18 if __name__ == '__main__':
19 main()
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On saute dans le code
-> def main():
(Pdb) ll
15 -> def main():
16 with open('events.csv') as stream:
17 for event in get_events(stream):
18 print(event.name, event.date)
19 print(Event.id)
(Pdb) step
> events.py(16)main()
-> with open('events.csv') as stream:
(Pdb) ll
15 def main():
16 -> with open('events.csv') as stream:
17 for event in get_events(stream):
18 print(event.name, event.date)
19 print(Event.id)
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On saute dans le code
(Pdb) next
> events.py(17)main()
-> for event in get_events(stream):
(Pdb) ll
15 def main():
16 with open('events.csv') as stream:
17 -> for event in get_events(stream):
18 print(event.name, event.date)
19 print(Event.id)
(Pdb) step
--Call--
> events.py(11)get_events()
-> def get_events(stream):
(Pdb) ll
11 -> def get_events(stream):
12 for row in csv.reader(stream):
13 yield Event(*row)
(Pdb) next
> events.py(12)get_events()
-> for row in csv.reader(stream):
(Pdb) ll
11 def get_events(stream):
12 -> for row in csv.reader(stream):
13 yield Event(*row)
(Pdb)
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Breakpoints
Je reprends le code de base
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Breakpoints
(Pdb) ll
1 import pendulum
2 import csv
3
4 class Event:
5 def __init__(self, name, date):
6 self.name = name
7 self.date = pendulum.parse(date)
8
9 def get_events(stream):
10 for row in csv.reader(stream):
11 yield Event(*row)
12
13 def main():
14 with open('events.csv') as stream:
15 for event in get_events(stream):
16 print(event.name, event.date)
17
18 if __name__ == '__main__':
19 main()
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Breakpoints
Lister
> events.py(1)()
-> import pendulum
(Pdb) break
(Pdb)
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Breakpoints
Ajouter
> events.py(1)()
-> import pendulum
(Pdb) break 9
Breakpoint 1 at events.py:9
(Pdb) l
4 class Event:
5 id = 0
6 def __init__(self, name, date):
7 self.id += 1
8 self.name = name
9 B-> self.date = pendulum.parse(date)
10
11 def get_events(stream):
12 for row in csv.reader(stream):
13 yield Event(*row)
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Breakpoints
Ajouter
> events.py(1)()
-> import pendulum
(Pdb) break 9
Breakpoint 1 at events.py:9
(Pdb) l
4 class Event:
5 id = 0
6 def __init__(self, name, date):
7 self.id += 1
8 self.name = name
9 B-> self.date = pendulum.parse(date)
10
11 def get_events(stream):
12 for row in csv.reader(stream):
13 yield Event(*row)
(Pdb) break
Num Type Disp Enb Where
1 breakpoint keep yes at events.py:9
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Breakpoints
Désactiver un breakpoint
(Pdb) disable 1
Disabled breakpoint 1 at events.py:9
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Breakpoints
Désactiver un breakpoint
(Pdb) disable 1
Disabled breakpoint 1 at events.py:9
(Pdb) break
Num Type Disp Enb Where
1 breakpoint keep no at events.py:9
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Breakpoints
Activer un breakpoint
(Pdb) enable 1
Enabled breakpoint 1 at events.py:9
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Breakpoints
Activer un breakpoint
(Pdb) enable 1
Enabled breakpoint 1 at events.py:9
(Pdb) break
Num Type Disp Enb Where
1 breakpoint keep yes at events.py:9
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Je continue
(Pdb) continue
> events.py(9)__init__()
-> self.date = pendulum.parse(date)
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J'examine
(Pdb) args
self = <__main__.Event object at 0x7f23cf8cc908>
name = 'PyCon France'
date = '2017-09-21'
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J'examine
(Pdb) args
self = <__main__.Event object at 0x7f23cf8cc908>
name = 'PyCon France'
date = '2017-09-21'
(Pdb) whatis name
(Pdb) whatis self
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Nouvelles commandes avec alias
alias d pp dir(%1)
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Nouvelles commandes avec alias
alias d pp dir(%1)
(Pdb) b 9
Breakpoint 1 at events.py:9
(Pdb) c
> events.py(9)__init__()
-> self.date = pendulum.parse(date)
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Nouvelles commandes avec alias
alias d pp dir(%1)
(Pdb) b 9
Breakpoint 1 at events.py:9
(Pdb) c
> events.py(9)__init__()
-> self.date = pendulum.parse(date)
(Pdb) d self.__dict__
['__class__',
'__contains__',
'__delattr__',
...
]
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Nouvelles commandes avec alias
alias loc !list(locals().keys())
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Nouvelles commandes avec alias
alias loc !list(locals().keys())
(Pdb) loc
dict_keys(['date', 'name', 'self'])
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Nouvelles commandes avec alias
alias printdict for key, value in %1.items(): print(f"{key}:{value}")
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Nouvelles commandes avec alias
alias printdict for key, value in %1.items(): print(f"{key}:{value}")
(Pdb) printdict self.__dict__
id:1
name:PyCon France
date:2017-09-21T00:00:00+00:00
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Réutilisation d'alias
alias pd printdict %1
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Réutilisation d'alias
alias pd printdict %1
(Pdb) pd self.__dict__
id:1
name:PyCon France
date:2017-09-21T00:00:00+00:00
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Breakpoint et une action
Possibilité de définir une action lors d'un breakpoint
commands [bpnumber]
p self.__dict__
printdict self.__dict__
end
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Démonstration
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PDB
Récapitulatif des commandes
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Les importantes
Commande Description
h(elp) Affiche l'aide
h(elp) command Affiche l'aide d'une commande
q(uit) Quitte le debuggeur
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Examiner
Commande Description
p(rint) expr Affiche la valeur de l'expression
pp expr Pretty-print de la valeur de l'expression
l(ist) Affiche une partie du code
ll Affiche toute le code de la fonction
a(rgs) Affiche la liste des arguments de la fonction
whatis arg Affiche le type de l'argument
where Mais ou se trouve l'exception
source Affiche la source d'une fonction
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Naviguer
Commande Description
n(ext) Exécute l'instruction
s(tep) Exécute et rentre dans la fonction/méthode
r(eturn) Continue l'exécution jusqu'au return
c(ontinue) Continue l'exécution jusqu'à un breakpoint
u(p) Remonte d'un niveau dans la stack trace
d(own) Descend d'un niveau dans la stack trace
j(ump) lineno Saute a la ligne
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Breakpoints
Commande Description
b(reak) Montre tous les breakpoints
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Breakpoints
Commande Description
b(reak) lineno Place un breakpoint à lineno
b(reak) lineno,
cond
Place un breakpoint à lineo si cond est True
b(reak)
file:lineno
Place un breakpoint dans le fichier file à la ligne
lineno
b(reak) func
Place un breakpoint à la première ligne de la
fonction func
tbreak lineno Place un breakpoint et l'enleve dès que l'on y est
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Breakpoints
Commande Description
clear bpnumber Supprime un breakpoint
disable bpnumber Désactive un breakpoint
enable bpnumber Active un breakpoint
ignore bpnumber count Ignore le breakpoint X fois
condition bpnumber condition Permet de modifer le breakpoint
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Celles que vous ne connaissez pas ;-)
Commande Description
!expr
Execute une expression dans l'interpreteur
Python
alias Créer une nouvelle commande PDB
unalias Supprime un alias
commands
[bpnumber]
Assigne des commandes à un breakpoint
restart or run Redémarre le script
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Fichier de con guration
alias d pp dir(%1)
alias ps d self.__dict__
alias loc !list(locals().keys())
alias printdict for key, value in %1.items(): print(f"{key}:{value}")
Voir $HOME/.pdbrc ou ./.pdbrc
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Il y a un truc amusant
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Ça fonctionne avec ipdb
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Les alternatives - ipdb
Auto-completion
Coloration syntaxique
Meilleurs tracebacks
Meilleur introspection
Commandes supplémentaires
https://github.com/gotcha/ipdb
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Les alternatives - pudb
https://github.com/inducer/pudb
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Les alternatives - rdb
import pdb, socket, sys # noqa --> Pas PEP8
class Rdb(pdb.Pdb):
def __init__(self, port=4444):
self.old_stdout = sys.stdout
self.old_stdin = sys.stdin
self.skt = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.skt.bind(('localhost', port))
self.skt.listen(1)
(clientsocket, address) = self.skt.accept()
handle = clientsocket.makefile('rw')
pdb.Pdb.__init__(self, completekey='tab', stdin=handle, stdout=handle)
sys.stdout = sys.stdin = handle
def do_continue(self, arg):
sys.stdout = self.old_stdout
sys.stdin = self.old_stdin
self.skt.close()
self.set_continue()
return 1
do_c = do_cont = do_continue
https://dzone.com/articles/remote-debugging-python-using
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Les alternatives - rdb (2)
# Example usage - connect with 'telnet 4444'
if __name__=='__main__':
def buggy_method():
x = 3
remote_debug = Rdb()
remote_debug.set_trace()
print(x)
buggy_method()
https://dzone.com/articles/remote-debugging-python-using
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Les alternatives - rdb (3)
telnet localhost 4444
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
> rdb.py(32)buggy_method()
-> print(x)
(Pdb) ll
28 def buggy_method():
29 x = 3
30 remote_debug = Rdb()
31 remote_debug.set_trace()
32 -> print(x)
(Pdb) p x
3
(Pdb) quit
Connection closed by foreign host.
Meilleure implémentation dans
https://github.com/celery/celery/blob/master/celery/contrib/rdb.py
https://dzone.com/articles/remote-debugging-python-using
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Les alternatives - wdb
https://github.com/Kozea/wdb
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Les alternatives - pdbpp
https://github.com/antocuni/pdb
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pdb ou ipdb avec du dev Web
Par exemple, Django
django-pdb avec --ipdb ou --pdb
ou simplement
python -m pdb ./manage.py test
python -m ipdb ./manage.py test
python -m pudb ./manage.py test
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GNU Debugger
Également nommé gdb, GNU Debugger, est le débuggeur standard du projet
GNU, portable et fonctionne pour plusieurs langages, comme le C, le C++ et aussi
le Python ;-)
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GNU Debugger
gdb >= 7 , support natif de Python
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GNU Debugger
Avoir les symboles de debug de Python
$ dnf install python3-debug
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GNU Debugger
Avoir les symboles de debug de Python
$ dnf install python3-debug
ou
$ ./configure --prefix=$PWD-build --with-pydebug
$ make
$ make install
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GNU Debugger
Python + gdb = ?
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GNU Debugger
Python + gdb = ?
1. il y a une librairie pour debugger votre script Python depuis gdb
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GNU Debugger
Python + gdb = ?
1. il y a une librairie pour debugger votre script Python depuis gdb
2. gdb est extensible via Python
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Que faire avec gdb ?
Commande Description
py-bt Montre la stack trace Python
py-bt-full py-bt mais en plus verbeux
py-list Liste le code Python
py-print Affiche le contenu d'une variable Python
py-locals Affiche les locals
py-up Remonte d'une frame
py-down Descend d'une frame
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Le code
import time
import os
def next(i):
print(f"{os.getpid()} {time.strftime('%H:%M:%S')}")
time.sleep(10)
i = 1 - i
i = 1
while True:
next(i)
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Le code
import time
import os
def next(i):
print(f"{os.getpid()} {time.strftime('%H:%M:%S')}")
time.sleep(10)
i = 1 - i
i = 1
while True:
next(i)
$ python ex_loop1.py
10619 06:14:24
10619 06:14:34
10619 06:14:44
10619 06:14:54
10619 06:15:04
10619 06:15:14
PID 10619
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Comment faire ?
$ gdb -p 10619
GNU gdb (GDB) Fedora 8.0.1-26.fc26
...
For help, type "help".
Type "apropos word" to search for commands related to "word".
Attaching to process 10619
Reading symbols from /usr/bin/python3.6dm...Reading symbols from /usr/lib/debug/us
Reading symbols from /lib64/libpython3.6dm.so.1.0...Reading symbols from /usr/lib/d
Reading symbols from /lib64/libpthread.so.0...Reading symbols from /usr/lib/debug/
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
Reading symbols from /lib64/libdl.so.2...Reading symbols from /usr/lib/debug/usr/li
Reading symbols from /lib64/libutil.so.1...Reading symbols from /usr/lib/debug/usr
Reading symbols from /lib64/libm.so.6...Reading symbols from /usr/lib/debug/usr/li
Reading symbols from /lib64/libc.so.6...Reading symbols from /usr/lib/debug/usr/li
Reading symbols from /lib64/ld-linux-x86-64.so.2...Reading symbols from /usr/lib/de
0x00007f40dc696ce3 in __select_nocancel () at ../sysdeps/unix/syscall-template.S:84
84 T_PSEUDO (SYSCALL_SYMBOL, SYSCALL_NAME, SYSCALL_NARGS)
(gdb)
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Slide 90
Slide 90 text
A cher le code
(gdb) py-list
1 import time
2 import os
3
4 def next(i):
5 print(f"{os.getpid()} {time.strftime('%H:%M:%S')}")
>6 time.sleep(10)
7 i = 1 - i
8
9 i = 1
10 while True:
11 next(i)
(gdb)
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Slide 91
Slide 91 text
A cher la traceback
(gdb) py-bt
Traceback (most recent call first):
File "ex_loop1.py", line 6, in next
time.sleep(10)
File "ex_loop1.py", line 11, in
next(i)
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Slide 92
Slide 92 text
A cher la traceback avec plus d'infos
(gdb) py-bt-full
#3
#7 Frame 0x55c890804748, for file ex_loop1.py, line 6, in next (i=1)
time.sleep(10)
#12 Frame 0x55c890804458, for file ex_loop1.py, line 11, in ()
next(i)
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Slide 93
Slide 93 text
A cher la traceback avec plus d'infos
(gdb) py-bt-full
#3
#7 Frame 0x55c890804748, for file ex_loop1.py, line 6, in next (i=1)
time.sleep(10)
#12 Frame 0x55c890804458, for file ex_loop1.py, line 11, in ()
next(i)
(gdb) select-frame 7
(gdb) info locals
tstate = 0x55c8907a3cf0
(gdb) select-frame 3
(gdb) info locals
func = 0x7f40d5974418
meth = 0x7f40dd57c6c6
self =
result = 'sleep'
flags = 8
__PRETTY_FUNCTION__ = "_PyCFunction_FastCallDict"
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Slide 94
Slide 94 text
Examiner une frame
(gdb) py-bt-full
#3
#7 Frame 0x55706036f748, for file ex_loop1.py, line 6, in next (i=1)
time.sleep(10)
#12 Frame 0x55706036f458, for file ex_loop1.py, line 11, in ()
next(i)
(gdb) select-frame 7
(gdb) py-list
1 import time
2 import os
3
4 def next(i):
5 print(f"{os.getpid()} {time.strftime('%H:%M:%S')}")
>6 time.sleep(10)
7 i = 1 - i
8
9 i = 1
10 while True:
11 next(i)
(gdb) py-print i
local 'i' = 1
(gdb) py-locals
i = 1
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Slide 95
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Navigation
(gdb) py-down
Unable to find a newer python frame
(gdb) py-up
#7 Frame 0x55c890804748, for file ex_loop1.py, line 6, in next (i=1)
time.sleep(10)
(gdb) py-down
#3
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Slide 96
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Backtrace de CPython
(gdb) bt
#0 0x00007f40dc696ce3 in __select_nocancel () at ../sysdeps/unix/syscall-template
#1 0x00007f40dd57e7f8 in pysleep (secs=10000000000)
at /usr/src/debug/Python-3.6.2/Modules/timemodule.c:1438
#2 0x00007f40dd57c73d in time_sleep (self=, obj=
at /usr/src/debug/Python-3.6.2/Modules/timemodule.c:235
#3 0x00007f40dd39a9af in _PyCFunction_FastCallDict (
func_obj=,
args=0x55c8908048e0, nargs=1, kwargs=0x0)
at /usr/src/debug/Python-3.6.2/Objects/methodobject.c:209
#4 0x00007f40dd39ada6 in _PyCFunction_FastCallKeywords (
func=,
stack=0x55c8908048e0, nargs=1, kwnames=0x0)
at /usr/src/debug/Python-3.6.2/Objects/methodobject.c:294
#5 0x00007f40dd4b046e in call_function (pp_stack=0x7ffd7bcab7b8, oparg=1, kwnames=
at /usr/src/debug/Python-3.6.2/Python/ceval.c:4809
#6 0x00007f40dd4a8046 in _PyEval_EvalFrameDefault (
f=Frame 0x55c890804748, for file ex_loop1.py, line 6, in next (i=1), throwflag=
at /usr/src/debug/Python-3.6.2/Python/ceval.c:3295
#7 0x00007f40dd494118 in PyEval_EvalFrameEx (
f=Frame 0x55c890804748, for file ex_loop1.py, line 6, in next (i=1), throwflag=
at /usr/src/debug/Python-3.6.2/Python/ceval.c:718
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Slide 97
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Threads
(gdb) info threads
Id Target Id Frame
1 Thread 0x7f40ddaef700 (LWP 10619) "python3-debug" 0x00007f40dd39a9af in _PyC
args=0x55c8908048e0, nargs=1, kwargs=0x0)
at /usr/src/debug/Python-3.6.2/Objects/methodobject.c:209
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Slide 98
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Dumper les stack traces des threads
(gdb) thread apply all py-bt
Thread 1 (Thread 0x7f40ddaef700 (LWP 10619)):
Traceback (most recent call first):
File "ex_loop1.py", line 6, in next
time.sleep(10)
File "ex_loop1.py", line 11, in
next(i)
(gdb)
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Slide 99
Slide 99 text
Débugger à distance
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Slide 100
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Mode Remote - gdbserver
$ gdbserver --multi host:2345
#
# ou ces modes-ci
#
$ gdbserver host:2345 process_name
$ gdbserver host:2345 --attach PID
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Slide 101
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Mode Remote - gdbserver
$ gdbserver --multi host:2345
#
# ou ces modes-ci
#
$ gdbserver host:2345 process_name
$ gdbserver host:2345 --attach PID
$ gdb
(gdb) target extended-remote host:2345
(gdb) attach PID
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Slide 102
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Mode Remote - gdbserver
$ gdbserver --multi host:2345
#
# ou ces modes-ci
#
$ gdbserver host:2345 process_name
$ gdbserver host:2345 --attach PID
$ gdb
(gdb) target extended-remote host:2345
(gdb) attach PID
(gdb) py-list
1 import time
2 import os
3
4 def next(i):
5 print(f"{os.getpid()} {time.strftime('%H:%M:%S')}")
>6 time.sleep(10)
7 i = 1 - i
8
9 i = 1
10 while True:
11 next(i)
(gdb)
101 / 107
Slide 103
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Extensible ?
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Slide 104
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Extensible ? - Oui
https://github.com/cyrus-and/gdb-dashboardOui
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Alternatives
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Slide 106
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gdbgui
pip install gdbgui
105 / 107
Slide 107
Slide 107 text
Prochaines talks pour 2018
SystemTap et DTrace pour mon Python
Que fait mon débuggeur Python?
GDB en profondeur
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