Nebula - 3.1.2

Nebula 3.1.2 - Release Notes

What’s New

⚠️ Behavior change: Automatic response wrapping has been introduced.

Route return values are now automatically converted into the appropriate response type, removing the need to explicitly specify return_class in most cases.

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New Behavior

Previously, you had to define a response class explicitly:

@app.get("/", return_class=HTMLResponse)
async def root() -> None:
    return "<h1>Welcome to Nebula!</h1>"

Now, Nebula automatically detects the response type:

@app.get("/")
async def root() -> None:
    return "<h1>Welcome to Nebula!</h1>"

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Auto-Detection Rules

Nebula will now automatically wrap return values using the following rules:

• dict or list → JSONResponse

• str:

  • Starts with < → HTMLResponse
  • Otherwise → PlainTextResponse

• Other types → converted to str and wrapped in PlainTextResponse

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Examples

✅ JSON Response (automatic)

@app.get("/json")
async def json_route():
    return {"message": "Hello, world!"}

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✅ HTML Response (automatic)

@app.get("/html")
async def html_route():
    return "<h1>Hello, world!</h1>"

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✅ Plain Text Response (automatic)

@app.get("/text")
async def text_route():
    return "Hello, world!"

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❌ Old behavior (no longer required)

@app.get("/", return_class=HTMLResponse)
async def root() -> None:
    return "<h1>Welcome to Nebula!</h1>"

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Migration Guide

If your routes previously relied on return_class, you can safely:

• ❌ Remove return_class from your route definitions
• ✅ Keep your return values unchanged

Before

@app.get("/", return_class=HTMLResponse)
async def root() -> None:
    return "<h1>Welcome to Nebula!</h1>"

After

@app.get("/")
async def root() -> None:
    return "<h1>Welcome to Nebula!</h1>"

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Notes

• This change simplifies route definitions and reduces boilerplate.
• Response behavior is now inferred automatically based on return type.
• You can still explicitly return a Response instance to bypass auto-detection.