debugging openstack with pdb

在要开始debug的地方导入pdb：

class KeypairAPI(base.Base):
    """Sub-set of the Compute Manager API for managing key pairs."""
    def __init__(self, **kwargs):
        super(KeypairAPI, self).__init__(**kwargs)

    def _validate_keypair_name(self, context, user_id, key_name):

        import pdb; pdb.set_trace()       

        safechars = "_- " + string.digits + string.ascii_letters
        clean_value = "".join(x for x in key_name if x in safechars)

然后触发该代码，如执行cli命令等，然后用screen打开后台就会看到如下：

.
.
2013-03-26 19:56:26 71243 DEBUG nova.utils [-] Reloading cached file /etc/nova/policy.json read_cached_file /usr/lib/python2.6/site-packages/nova/uti1
2013-03-26 19:56:27 INFO nova.api.openstack.wsgi [req-9ef1fd31-0cec-4465-894a-f1ae0fa9a77e 320ce46de7e24a75a7ff8906d7355ff7 57ff99aae24b4035b52177a72s
> /usr/lib/python2.6/site-packages/nova/compute/api.py(2198)_validate_keypair_name()
-> safechars = "_- " + string.digits + string.ascii_letters
(Pdb)
(Pdb)  n
> /usr/lib/python2.6/site-packages/nova/compute/api.py(2199)_validate_keypair_name()
-> clean_value = "".join(x for x in key_name if x in safechars)
(Pdb)  safechars
 '_- 0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ' 
(Pdb)
(Pdb)  quit

debug完后输入quit继续运行。

debug好之后不要忘了Remove the debugging fragment from the source file. Start the server daemon gracefully —

ref： https://kashyapc.com/2013/03/27/debugging-nova-a-small-illustration-with-pdb/