3.2. Custom Modifications

Apart from usual previous steps:

• We can now add the custom classes, modules to be accessible over jinja templates.

• We can now override device var databse with custom (regional_file) database.

Refer below details on how to use them.

• Full module import should declare pure methods only.

• Classes should be imported explicitely from diverse modules.

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Detailed How To

1. Import necessary custom class(es) from module, and/or import necessary module(s).

   Below depicts a Sample Code. Modify it as per your custom class(es) requirements.

   # Imports
   from custom_j2config.classes import Summaries, Vrf, Vlan, Bgp, Physical
   from custom_j2config import module1
   from custom_j2config.regional import Region    # available for j2config verion > 0.0.6
   
   # Custom global/Regional static variable excel database to override device local variables (optional)
   regional_file = 'global.xlsx'                # point to custom file
   

2. Include all imported classes and modules in to a dictionary and set respectively as given sample below.

   custom_classes = {           ### add all impored classes here ###
           'Summaries': Summaries,
           'Vrf': Vrf,
           'Vlan': Vlan,
           'Bgp': Bgp,
           'Physical': Physical
   }
   custom_modules = {module1, }  ### add all imported modules here ###
   

3. Modify PrepareConfig instance filters (created in previous page)

   ### From previous step ###
   PrCfg = PrepareConfig(
           data_file=data_file,
           jtemplate_file=template_file,
           output_folder=output_path,             ## optional (default: ".")
           regional_file=regional_file,           ## default: None
           regional_class=Region                  ## default: None
   )
   
   ### Add below two additional steps to include custom class/module methods as filter to jinja processsing.
   ### 1. Add Custom classes to above instance using `custom_class_add_to_filter`.
   PrCfg.custom_class_add_to_filter(**custom_classes)
   
   ### 2. Add Custom modules to above instance using `custom_module_methods_add_to_filter`.
   PrCfg.custom_module_methods_add_to_filter(*custom_modules)
   

4. Start configuration generation

   PrCfg.start()
   

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Note

Congratulations!!!

1. Hurrey!!! Now you can access custom declared classes/methods from within jinja template.

2. And you can override device var database using custom regional_file database.

Notice

• Make a note that output generates based on jinja template and template variables.

• It is soleley users responsiblity for providing appropriate filters as custom_classes and custom_modules, as well as using those in jinja templates.

• Make sure to cross-check the generated facts before using it.