Remaining path ../<path:path> not triggered when path is empty ('root node')

[matthimue]

In my application I need the remaining path …../example/remaining to be represented as a List.
For the root I need and expect an empty list.

However, using <path:path> handler, an empty path is not triggered for the root, which excludes handling the root node

a) …../example/ -> []   #root, empty list
b) …../example/a/b,c -> ['a','b','c'] #any, non empty list, ordered by hierarchy

So Miguel it would be great to have a look in this.

My recommendation would be, to
- let <path:path> trigger also when remaining path is empty to be able to handle root node
- and/or add a pathList handler (see below) to the microdot implementation as it makes really sense in number of implementations

…so see below what i found out

I tried the following with 3 implementations

1) using regular remaining path path:path

Does not work as it did only trigger for b) when remaining path is NOT empty, not for a) when remaing path IS empty
Instead I get "GET /testA/ 404" from microdot

@app.get('/testA/<path:path>')
async def index(request,path):
pathList = list(filter(lambda x: x.strip(), path.strip('/').split('/')))
print(path, " => ", pathList)
return

2) using regular regular expression

It does trigger for a) and b) so I could convert empty string to an empty list
Although I get "GET /testB/ 204" from microdot

@app.get('/testB/<re:[\x20-\x7E]*:path>')
async def index(request,path):
pathList = list(filter(lambda x: x.strip(), path.strip('/').split('/')))
print(path, " => ", pathList)
return

3) register a 'pathList' handler, my preferred solution

It does trigger for a) and b) and the handler returns the path as an empty list
Although I get "GET /testC/ 204" from microdot

@app.get('/testC/<pathList:path>')
async def index(request,path):
print(path)
return

URLPattern.register_type('pathList',
pattern = '[\x20-\x7E]*',
parser=lambda path: list(filter(lambda x: x.strip(), path.strip('/').split('/'))))

[miguelgrinberg]

The way I have always done this is with two handlers:

@app.get('/test')
@app.get('/test/<path:path>')
async def test(request, path=''):
    pass

Doesn't this address your issue?

[matthimue]

Thx! for the hint. In that case I would include /test/ instead of /test, not to leave /test/ unhandled. This I think is more convenient to trigger this path.
@app.get('/test/)
@app.get('/test/path:path')
async def test(request, path=''):
# add code here to convert path to list (or other conversion).....
pass

As said, I need to convert path to a list, and apply the conversion to other path as well, to share and simplify code.
Lists are often used, when matching paths to JSON structures in REST API implementations.
Then it would be great having something like 'pathList:path' simply in the library (which of course including empty list to point to the root)

That's the reason for a proposal. then the usage is just simple.

../AAA/pathlist:path
../BBB/pathlist:path
../CCC/pathlist:path

Without, it's always possible to register an own handler, as I implemented in my trial 3) before.

[miguelgrinberg]

A custom handler is the best option in this case, I do not feel a pathlist format is going to have wide use.

Lists are often used, when matching paths to JSON structures in REST API implementations.

I think the most common solution for this (if I understand what you are saying correctly) is jsonpath.