Issue with malformed `base_url`s

[mxub]

Hey everyone,

I just ran into an issue where the following code results in a 404 error:

settings = Req.new(
  base_url: "https://api.apaleo.com/settings/v1",
  auth: {:bearer, access_token},
  headers: [
    "content-type": :"application/json",
  ]
)

Req.get!(settings, url: "/properties/TEST")

Thats because URI.merge("https://api.apaleo.com/settings/v1", "/properties/TEST") results in "https://api.apaleo.com/properties/TEST".

I think it should be mentioned somewhere that a trailing / in the :base_url an no leading one in the :url are less error prone.

Maybe the readme should feature that style?

[wojtekmach]

Thank you for the report. This is a bug, what you expected should work. A PR is appreciated.

[wojtekmach]

btw,

headers: [
  "content-type": :"application/json",
]

can be also written as:

headers: [
  "content-type": "application/json",
]

or

headers: [
  content_type: "application/json",
]

it is fine as is of course :)

[mxub]

But what is the intended way? Would a simple

"https://api.apaleo.com/settings/v1" <> "/properties/TEST"

more sufficient than

URI.merge("https://api.apaleo.com/settings/v1", "/properties/TEST")

otherwise we should define the behavior beforehand and than implement it.

[wojtekmach]

not quite. If :url contains a full url (has schema), :base_url is ignored. That's why we went with URI.merge as it does it already.

[wojtekmach]

in terms of specifying the behaviour I'm thinking about something like this. wdyt?

base_url	url	result
https://a.com	x	https://a.com/x
https://a.com	/x	https://a.com/x
https://a.com/x	y	https://a.com/x/y
https://a.com/x	/y	https://a.com/x/y
https://a.com	https://b.com	https://b.com

but happy to make it stricter, reject some of the values, if that would make the implementation simpler and/or be more predictable.

[mxub]

base_url	url	expected result	URI result	Comments
https://a.com	x	https://a.com/x	https://a.com/x	same
https://a.com	/x	https://a.com/x	https://a.com/x	same
https://a.com/x	y	https://a.com/x/y	https://a.com/y	trailing / missing
https://a.com/x/	y	https://a.com/x/y	https://a.com/x/y
https://a.com/x	/y	https://a.com/x/y	https://a.com/y
https://a.com/x/	/y	https://a.com/x/y	https://a.com/y
https://a.com/x/y	../foo	?	https://a.com/foo
https://a.com/x/y/	../foo	?	https://a.com/x/foo
https://a.com	https://b.com	https://b.com	https://b.com	same

I think we would win a lot by requiring the trailing / maybe even just appending it?

[wojtekmach]

Fixed in #132