Conventions¶
The primary benefit of using abstract
module is its ease of use combined
with long-term scalability. With it, abstraction is no longer a day-one,
front-load investment, but rather an “add a token as you need” dynamic system.
In order to fully reap the benefits offered by abstraction and allowing for sharing between teams and projects, considering following the conventions below during your coding.
Rules of Thumb¶
when creating a new library, adding the Abstraction-Enabled Package declaration at the root
__init__.py
file is always a good habit to get into. There’s no side effect and/or runtime costs.add your methods, modules as you see fit, but focus on on tackling one combination (tokenset) at a time (eg, start with writing libraries for your uut: iosxr/sunstone/latest)
always create
Lookup
objects for each device as one of the first things in your script’s CommonSetup section. This will ensure the rest of your script have proper access to abstracted packages & libraries.when needing to call/reference any library functions & classes, always do so through the
Lookup
object created above.when a new set of combination (tokensets) needs to be added, consider their relationships and group like-levels together.
if you started with the following for iosxr/sunstone/latest /my_lib/__init__.py /my_lib/file.py and now needs to add iosxr/enxr, consider refactoring to: /my_lib/iosxr/sunstone/__init__.py /my_lib/iosxr/sunstone/file.py /my_lib/iosxr/enxr/__init__.py /my_lib/iosxr/enxr/file.py remember - a module is just a folder. You're merely shuffling files.
create new tokens with meaningful names that reflects the set of differences it covers. Eg, os names, relese variants, branches, etc.
use python inheritance between your various implementations for… a variety of OOP-related benefits.
if your library requires a set of defaults, eg, fallback functions/classes when no tokens match, define them directly under the root package module. The engine will auto-fallback to it.
consider sharing your code with the rest of the community.
Follow PEP8 - module naming convention.
Library Structure¶
Always group methods and classes together using some form of system (such as by funtionality) into modules & submodules. This will add depth and struture to your libraries, simplifying user’s understanding & maintenance.
As abstracted packages and tokens are simply python packages and modules, the standard python Python Packages guidelines apply, and your directory structure should naturally fall into place.
Library Structure
-----------------
library_root/
|-- __init__.py # declare_package()
|
|-- module.py # any default (no token) modules
|-- submodule/ # and submodules.
| |-- __init__.py
| `-- submodule_module.py
|
|-- token_module/ # a new token
| |-- __init__.py # declare_token()
| |
| |-- module.py # token specific modules
| |-- submodule/ # and submodules
| | |-- __init__.py
| | `-- submodule_module.py
| |
| `-- token_subtoken_module/ # a token under another token
| |-- __init__.py # declare_token
| |-- module.py
| `-- submodule/ # ditto
| |-- __init__.py
| `-- submodule_module.py
|
...
Example Library
---------------
The following is implemented:
- generic reload, verify, configure ospf & interface
- iosxr default reload, configure interface
- iosxr/crs specific reload, configure interface
example_abstracted_module/
|-- __init__.py
|
|-- reload.py
|-- verify.py
|
|-- configure/
| |-- __init__.py
| |-- ospf.py
| `-- interface.py
|
|-- iosxr/
| |-- __init__.py
| |
| |-- reload.py
| |-- configure/
| | |-- __init__.py
| | `-- interface.py
| |
| `-- crs/
| |-- __init__.py
| |-- reload.py
| `-- configure/
| |-- __init__.py
| `-- interface.py
|
...