repository source should support a file system link to a index file like pip's --index-url for usage without a web server

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• I have searched the FAQ and general documentation and believe that my question is not already covered.

Feature Request

I somehow understand the discussions and reluctance here and here about pip's find-links and why it will not be added, even if this would be very useful for company repositories which don't want to maintain a webserver.

But pip --index-url allows to pass a local html file, like file:///c:/wheelhouse/simple/index.html or c:\wheelhouse\simple\index.html.

Tools like piprepo create a index.html file with links to the local file system.
This might not be as convenient as 'find-links', but it serves the same purpose.

Poetry's source could be able to deal with these these local files (Simple API Repository and Single Page Link Source).
A source could use the attribute path separate the use cases.

Examples for usage:

[[tool.poetry.source]]
name = "foo"
path = "file:///C:/wheelhouse/simple/index.html"

[[tool.poetry.source]]
name = "foo"
url = "C:\wheelhouse\simple\index.html"

[[tool.poetry.source]]
name = "foo"
url = "file:///C:/wheelhouse/simple/index.html"

No implementation files, tests, or entry points are named in the issue. Start by tracing how Poetry parses and resolves tool.poetry.source entries, then review the linked discussions before deciding how local index files and path versus URL configuration should be handled. Done means a source can use the demonstrated local file forms without a web server, with coverage for the supported cases.