python-typing-to-typscript-interface v1.0.0

TypedDict's -> Interface

Say your API is hosted with Django or Flask, type hinting API responses with Python's TypedDict is then an only sane thing to do.

from typing import TypedDict

class Book(TypedDict):
    pages: int
    chapters: List[Chapter]
    Authors: List[str]

class Chapter(TypedDict):
    title: str
    // short chapters only has one paragraph
    content: Union[str, List[Paragraph]]

class Paragraph(TypedDict):
    content: str

If your consumer uses typescript, then rewriting this file as a typescript interface is pretty much a necessity. This tool provides a CLI that does the conversion for you.

Our output:

interface Book {
    pages: number;
    chapters: Chapter[];
    Authors: string[];
}
interface Chapter {
    title: string;
    content: string | Paragraph[];
}
interface Paragraph {
    content: string;
}

Installation

npm i -D python-typing-to-typscript-interface

This creates CLI $ ptttts (Python Typing To TypeScript)

Usage Examples

$ ptttts schema.py schema.d.ts --python_interpreter venv/bin/python

$ ptttts path/to/python/script.py path/to/output.ts

Do $ ptttts -h to see details

Suggestion:

If you are a maintainer of your python API, consider having a schema.py file and set up automated @types/you-app npm package publish.

How

The program parses Python script with Python's built-in ast, and uses typescript's compiler APIs to transform the ast nodes.

Limitations

• This is currently in experimental stage. We mostly guaranteed it would work on our own schema.py. Some Python typing features are not coded in yet (to name a few: Any Dict dict Optional). Don't be sad! Most infrastructural work is already done in python_nodes.ts. It will be easy to support these features. Pull request / feature requests are welcome.
• You need to specify a python interpreter. It defaults to python3 if not provided
• The input file should only have TypedDicts classes. That is, no type aliases. Having extra code anywhere in the input file is OK, but code other than TypedDict classes will be ignored. For example if you use the below file as input, the first line User = string will be dropped.

  ```python
  User = string
  
  class Book(TypedDict):
      owner: User
      price: int
      ...
  ``` 
  output:
  
  ```typescript
  interface Book{
    owner: User
    price: int

  }

  ```