AnyUrl doesn't accept file URLs with implicit host

[torfsen]

Bug

Output of python -c "import pydantic.utils; print(pydantic.utils.version_info())":

             pydantic version: 1.5.1
            pydantic compiled: True
                 install path: /shared/conda/envs/ubide-mastr/lib/python3.6/site-packages/pydantic
               python version: 3.6.10 |Anaconda, Inc.| (default, May  8 2020, 02:54:21)  [GCC 7.3.0]
                     platform: Linux-5.4.0-48-generic-x86_64-with-debian-buster-sid
     optional deps. installed: []

import pydantic

class MyModel(pydantic.BaseModel):
    url: pydantic.AnyUrl

MyModel(url='file:///foo/bar')

raises:

ValidationError: 1 validation error for MyModel
url
  URL host invalid (type=value_error.url.host)

However, MyModel(url='file://hostname/foo/bar'), i.e. a URL with an explicit hostname, works.

RFC 8089 says that the hostname is optional. Hence I would expect that AnyUrl would accept that.

[samuelcolvin]

I guess we could add host_required like user_required, then make it true for most of the descendant types.

[harshach]

anyurl doesn't work for JDBC connection URL either "jdbc:mysql://localhost/test" invalid or missing URL scheme (type=value_error.url.scheme)

[dharmveer18]

I have made Optional[HttpUrl] = None, still not working