[openstack-dev] [all][monasca] pysnmp autogenerated code

[Stefano Canepa]

Hi Stefano,
The best solution would be of course to fix pysmi code generator [1]

to

behave. ;-)
​This is something that pysmi author already gives for granted in the
Release notes.
I bet you know this better then me ;-)​
On the other hand, if you won't include the autogenerated code into

your

package, the code generation would happen just once at run time - the
autogenerated module would get cached on the file system and loaded

from

there ever after.
Theoretically, not pinning Python MIB in your package has an

advantage

of letting pysmi pulling newer ASN.1 MIB and turning it into Python
whenever newer MIB revision becomes available.
​Ilya you're confusing me. Do you mean that, even if I load my MIB and
all other it depends on from ASN.1, they are compiled into python byte
code and cached and blah blah? ​

* pysnmp wants to load a MY-MIB by name (e.g. evaluate the contents of
MY-MIB.py, turn it into Python objects and link them up to its in-memory
MIB tree)
* pysnmp searches for MY-MIB.py[co] in its search path
* if pysnmp is successful, we are done
* if pysnmp does not find MY-MIB.py[co] and pysmi package is present,
pysnmp calls pysmi with MY-MIB name on input
* pysmi tries to find MY-MIB (e.g. in ASN.1 form) in its search path
(possibly including remote locations), compile it into MY-MIB.py[co] and
cache it somewhere within pysnmp search path
* if pysmi is successful, pysnmp starts over loading MY-MIB.py[co]
Hope this is helpful. ;)

Super helpful.

Copy&pasted this into my notebook for future reference.

All the best
Stefano

​