py-buzz 0.1.9

That's not flying, it's falling with style: Exceptions with extras

py-buzz

That’s not flying, it’s falling with style: Exceptions with extras

This package is a light-weight extension of python’s Exception class with some added niceties

Requirements

• Python 3

Installing

Install using pip:

$ pip install py-buzz

Using

Just import:

from buzz import Buzz
raise Buzz("something went wrong!")

Buzz also makes an excellent base-class for your project specific exception classes!

Features

Automatic message formatting

Buzz exception messages can be automatically formatted with format arguments and keyword arguments. This saves a few characters and generally makes the exception code a little easier to read:

# Vanilla python
raise Exception("a {} message".format('formatted'))
raise Exception("a {fmt} message".format(fmt='formatted'))

# With py-buzz
raise Buzz("a {} message", 'formatted')
raise Buzz("a {fmt} message", fmt='formatted')

Obviously the benefits aren’t that easy to see with a small message with few args, but getting rid of an additional level of nesting can be nice with more complex messages

Raise exception on condition failure

Buzz provides a function that checks a condition and raises an exception if it fails. This is nice, because you often find your self writing a lot of if <whatever>: raise Exception(<message>) throughout your code base. Buzz makes it just a little easier to write and read that kind of code:

# Vanilla python
if not some_condition():
    raise Exception("some_condition failed")

# With py-buzz
Buzz.require_condition(some_condition(), "some_condition failed")

This is again justa bit of syntactic sugar but can make code a bit more palletable, especially if you have to check a lot of invariants in a function

Exception handling context manager

Buzz also provides a context manager that catches any exceptions that might be caught in executing a bit of code. The caught exceptions are re-packaged as Buzz errors and re-raised with a message that captures the initial exception’s message:

# Vanilla python
try:
   this_could_fail()
   this_could_also_fail()
   this_will_definitely_fail()
except Exception as err:
    raise Exception("Something didn't work -- Error: {}".format(str(err)))

# With py-buzz
with Buzz.handle_errors("Something didn't work"):
   this_could_fail()
   this_could_also_fail()
   this_will_definitely_fail()

This actually can save a bit of code and makes things a bit cleaner. It is also a pattern that tends to get repeated over and over again. If more complex error handling logic is needed, this context manager shouldn’t be used. It is intended to just handle simple re-packaging of exceptions in a block of code