HOPE-10-Prefixes-and-Suffixes.md

HOPE 10 -- Prefixes and Suffixes

HOPE:	10
Title:	Prefixes and Suffixes
Author(s):	Timothy Crosley timothy.crosley@gmail.com
Status:	Provisional
Type:	Standards Track
Created:	11-June-2019
Updated:	11-June-2019

Abstract

This HOPE proposes new standardized behavior for Hug prefixes and suffixes.

Problem Statement

Currently, Hug interface routers expose a prefixes and suffixes argument to allow supporting multiple extensions, but they don't enable cases where you don't want to expose the original endpoints. This behavior is also currently not well defined across interface types and the logic behind the behavior not well laid out. This is well illustrated by this hug ticket inquiring about the behavior.

Proposed Solution

All interface routers that expose the concept of prefixes and suffixes should accept the arguments against the following signature:

@interface_router(prefixes: Union[List, str, None], suffixes: Union[List, str, None])

If a string is passed in, it should be handled identically to that same string being passed in as the only element in a list: [str]. If suffixes or prefixes are set, the router should replace the current endpoint list with one that is expanded to include each of the provided suffixes and prefixes. This would mean by default, the un-suffixed or prefixed endpoints would no longer be accessible.

The old behavior would still be achievable by explicitly adding empty items to the list.

Old:

@hug.get(suffixes=["json", "html"])
def my_endpoint():
    ...

New:

@hug.get(suffixes=["json", "html", ""])
def my_endpoint():
    ...