Exceptions

A curated list of custom exception types defined in the uriel program.

Each of these subclass the Python Exception class directly with no additional modifications.

Exception	Purpose
SojuError	Represents an error from user-defined soju code that should not throw a stack trace.
HandlerError	Represents an error from user-defined handler code that should not throw a stack trace.

You can throw these exceptions from your own user-defined code.

If you throw these exceptions from their expected contexts, Uriel will show the error message, along with information about how that code ended up getting executed. However, if you throw these exceptions, Uriel will omit additional detailed traceback information.

If you are handling an error where you understand the general cause, throwing one of these exceptions can make the error messages a little bit less verbose.

Throw SojuError From User-Defined Soju Function

# lib/soju.py
def hello_world(node):
    raise SojuError("oops")

When the exception is raised, Uriel will display an error that looks like this:

copying 'static' to 'public', overwriting previous contents
initializing soju
initializing handlers
reading node files
rendering node content
parameter error:
  nodes/parameters/soju-hello-world
    templates/default.html
      nodes/parameters/soju-hello-world
        '{{soju:hello_world(node)}}'
          'oops'
soju: error in function call to 'soju.hello_world(node)': 'oops'

Throw HandlerError From User-Defined Handler Function

# lib/handlers.py
def init(project_root):
    raise HandlerError("oops")

When the exception is raised, Uriel will display an error that looks like this:

copying 'static' to 'public', overwriting previous contents
initializing soju
initializing handlers
running handler: init
uriel: error in handler function init(): 'oops'

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