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jdev 10-11-2017 01:59 PM

Example: Python - Importing custom modules referencing the 'crt' object
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These examples provide techniques for importing your custom-written python modules that need to reference the crt scripting object.

The main script (which imports the module code) performs this sequence of actions:
  1. sys.dont_write_bytecode = True
    This statement is used to PREVENT python from automatically creating .PYC files. Otherwise, coding, testing, and revising your module's functionality would prove cumbersome and confusing since python imports the .PYC file (which doesn't reflect your current code) if it exists.

  2. import crt_module
    This is the line of code that tells the python interpreter to import your module code, if it's not already in the sys.modules table.

  3. reload(crt_module)
    The python environment is initialized only once in SecureCRT at startup, and remains as-is until the SecureCRT process terminates. This means that once you run a script which imports a module, that module is in the sys.modules table for the lifetime of the SecureCRT process. If you are in the process of developing and testing a module, code changes you make will not be reflected unless you either:
    1. Restart SecureCRT
    2. Use the reload(crt_module) statement to reload the module code from your module's .py file.

  4. "Injects" the crt object into the module (so that statements within the module that reference the crt object won't result in an error). In this pair of example scripts,
    • the module code defines a method as Inject_crt_Object(obj_crt_API), which allows the crt application programming interface known to the main script to be used within the module code itself.
    • the main script's .py code, following the import(crt_module) and reload(crt_module) statements, calls the module's Inject_crt_Object method, passing in its copy of the crt object, as in: Inject_crt_Object(crt)

Files attached here include:

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