UML Class Diagram Generator

The UML Class Diagram Generator gives you full visibility into your Python object model by translating your class definitions into clear, standardized diagrams. It’s ideal for:

Documenting existing codebases without manually drawing diagrams.
Onboarding new team members with up‑to‑date architectural views.
Embedding live‑generated diagrams into design documents or README files.
Automating UML updates in your CI/CD pipeline to prevent drift.

Key Features

Inheritance (class Child(Parent):) is represented as a solid arrow with a triangle tip:
Python: class VIPUser(User): … UML: VIPUser --|> User
This helps visualize base classes, mixins, and framework extensions at a glance.
Associations based on constructor type hints:
Python: def __init__(self, order: Order): … UML: Customer --> Order
Automatically shows how objects reference each other, eliminating manual arrow drawing.
Visibility markers use + for public members and - for private ones:
Python: def _calculate(): … UML: - _calculate()
Clearly distinguishes internal implementation details from API methods.
Class attributes & defaults (e.g. MAX_RETRIES = 3) become fields:
Python: MAX_RETRIES = 3 UML: + MAX_RETRIES: int = 3
Documents constants and configurable settings alongside instance data.
Operations (methods) are listed under each class (excluding __init__):
Python: def process(self): … UML: + process()
Provides a quick API overview without digging into source code.
Ready‑to‑paste PlantUML: just wrap your output in @startuml…@enduml and render it in any PlantUML-compatible tool.

Before:

class Address():  
    def __init__(self, street: str, zip: str):  
        self.street = street  
        self.zip = zip  

class User(Address):  
    def __init__(self, name: str, address: Address):  
        super().__init__(address.street, address.zip)  
        self.name = name  
    def greet(self):  
        print(f'Hello {self.name}')

After (with all options):

@startuml  
class Address {  
  + street  
  + zip  
}  

class User {  
  + name  
  + greet()  
}  

User --|> Address  
User --> Address  
@enduml

Advanced Tips

Selective options: disable “associations” to hide crowded arrows, or disable “visibility” for a cleaner look when privacy details aren’t needed.
Grouping: use PlantUML’s package or namespace features around the output to group related classes.
Custom stereotypes & notes: after generation, you can append PlantUML tags like <<service>> or note right for additional context.
Embedding in CI: add a step to regenerate diagrams on each push and automatically commit updated .puml files to keep docs in sync.
Multi‑language support: although tailored for Python, you can adapt the output to other languages’ class syntaxes by minor PlantUML customization.

Once you have the markup:

Paste into any PlantUML renderer (PlantText, VS Code plugin, IntelliJ PlantUML). Instantly see class layouts and their relationships.
Embed diagrams inline in Markdown or AsciiDoc files using supported tags (e.g. GitLab’s ```puml blocks).
Use skinparam directives in PlantUML to adjust fonts, colors, and layout algorithms for consistent styling across projects.
Regenerate diagrams after each code change to maintain accurate architecture docs and avoid outdated visuals.
Share snapshots in pull requests or design discussions, providing both code and diagram side‑by‑side for faster reviews.

UML Class Diagram Generator

Key Features

Before:

After (with all options):

Advanced Tips

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