Remove the check for ':' when setting authority in wasi-http.

[rylev]

Authorities can have : in them when they are IPV6 addresses. With the current check it is impossible to use ipv6 addresses as authorities for outgoing http requests.

It's not clear to me why the check was added in the first place, so I might be missing something obvious here why the check is necessary.

[dicej]

It looks like the check for : was an attempt to validate this:

The HTTP and HTTPS schemes always require an authority. Fails if the string given is not a syntactically valid URI authority.

Presumably, that means it should not contain a port number. So if we update the check to ensure it doesn't end with a colon followed by zero or more digits (e.g. the regex :[0-9]*), that should allow IPv6 addresses but still disallow port numbers. EDIT: Disregard what I wrote. Reading the code more carefully, I see it was not trying to disallow specifying the port. I don't know what it was trying to do 🤷

[badeend]

From the PR that introduced this check, I can't reverse engineer why this check was added.

The URI authority can include the port. As matter of fact, it is the only way in the wasi-http interface to declare the port number.

Taking the code at face value, I think what it tried to check for is that: when a port is provided it shall be a valid u16. For example: http://bad-port:99999 is syntactically a valid URI authority, but 99999 is not a valid port number.
A better way to write this could be:

if auth.port().is_some() && auth.port_u16().is_none() {
   return Ok(Err(()));
}

Maybe there's still value in keeping such a validation around.

Other than that: I agree with the general sentiment of this PR: http::uri::Authority::from_str alone is likely better equipped to validate URI's than ad-hoc validations in wasmtime itself.

Could you add a test that checks a IPv6 address +/- a port number passes the validation? E.g. "[::]:443"

[rylev]

FYI: the check suggested of...

if auth.port().is_some() && auth.port_u16().is_none() {
   return Ok(Err(()));
}

... won't work as auth.port() already parses the port as a u16. So if auth.port().is_some() is true - auth.port_u16() will also be Some.

I have pushed a test for ipv6 with and without a port.

[badeend]

Hmm. I see. In that case, I don't know why that check was there.