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ReStructuredText
74 lines
2.6 KiB
ReStructuredText
Structuring Your Project
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Structuring your project properly is extremely important.
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.. todo:: Fill in "Structuring Your Project" stub
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Structure is Key
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----------------
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Thanks to the way imports and module are handled in Python, it is
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relatively easy to structure a python project. Easy, here, means
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actually that you have not many constraints and that the module
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importing model is easy grasp. Therefore, you are left with the
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pure architectural task of drawing the different parts of your
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project and their interactions.
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Easy structuration of a project means it is also easy
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to do it poorly. Some signs of a poorly structured projects
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include:
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- Multiple and messy circular dependencies: if your classes
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Table and Chair in furn.py need to import Carpenter from workers.py
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to answer to a question such as table.isdoneby(),
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and if convertly the class Carpenter need to import Table and Chair,
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for example to answer to carpenter.whatdo(), then you
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have a circular dependency, and will have to resort to
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fragile hacks such has using import statements inside
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methods or functions.
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- Hidden coupling. Each and every change in Table implementation
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breaks 20 tests in unrelated test cases because it breaks Carpenter's code,
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which requires very careful surgery to adapt the change. This means
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you have too many assumptions about Table in Carpenter's code or the
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reverse.
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- Heavy usage of global state or context: Instead of explicitely
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passing ``(height, width, type, wood)`` to each other, Table
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and Carpenter rely on global variables that can be modified
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and are modified on the fly by different agent. You need to
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scrutinize all access to this global variables to understand why
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a rectangular table became a sqaure, and discover that a remote
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template code is also modifying this context, messing with
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table dimensions.
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- Spaghetti code: Multiple pages of nested if clauses and for loops
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with a lot of copy-pasted procedural code and no
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proper segmentation are known as spaghetti code. Python's
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meaningful indentation (one of its most controversial feature) make
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it very hard to maintain this kind of code. So the good news is that
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you might not see too much of it.
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- Ravioli code is more likely in Python: it consists of hundreds of
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similar little pieces of logic, often classes or objects, without
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proper structure. If you never can remember if you have to use
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FurnitureTable, AssetTable or Table, or even TableNew for your
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task at hand, you might be swimming in ravioli code.
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Vendorizing Dependencies
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------------------------
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Runners
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-------
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Further Reading
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---------------
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