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JustAPI

Header Parameters

Basic Header Parameters

Section titled “Basic Header Parameters”
from justapi import JustAPIApp, Header


app = JustAPIApp()


@app.get("/items/")
def read_items(x_token: str = Header(...)):
    return {"x_token": x_token}

The header name X-Token is automatically converted to x_token (underscores).

Multiple Headers

Section titled “Multiple Headers”
@app.get("/users/")
def read_users(
    x_token: str = Header(...),
    x_request_id: str = Header(None),
):
    return {"x_token": x_token, "x_request_id": x_request_id}

Required vs Optional

Section titled “Required vs Optional”
  • Header(...) — required (the ... means “no default, required”)
  • Header(None) — optional, defaults to None
  • Header("default") — optional, defaults to "default"

Underscore Conversion

Section titled “Underscore Conversion”

By default, JustAPI converts dashes to underscores in header names. To disable this:

@app.get("/items/")
def read_items(custom_header: str = Header(..., convert_underscores=False)):
    return {"custom_header": custom_header}

Duplicate Headers

Section titled “Duplicate Headers”

For headers that can repeat (like Set-Cookie):

@app.get("/items/")
def read_items(x_token_list: list[str] = Header(...)):
    return {"x_token_list": x_token_list}

See Also

Section titled “See Also”