no error handling here?

needs a test, and an example in doc (link to PR against 1.10 doc branch)

looks like some options are not serialized in the AuthOptions struct. IdentityEndpoint in particular seems to be ignored. How would the Token() method know what server to contact?

How would the Token() method know what server to contact?

L62 func (t *tokenGetter) Token() will use this authOpt to get an authenticated client, where IdentityEndpoint will be used.

looks like some options are not serialized in the AuthOptions struct. IdentityEndpoint in particular seems to be ignored.

Good catch. AuthOptions omits this filed. We need to retrieve this value explicitly.

might be able to just compare straight: authOpt != gophercloud.AuthOptions{}

it's not good treat a single config struct as a mix of two API types (we expect a "ttl" key above, and this checks if they happened to specify keys that match the gophercloud.AuthOptions struct). what would happen if the gophercloud.AuthOptions struct added a ttl field that was an int?

this is another sign that this probably isn't the right approach.

if you want to populate options from inline config, I'd suggest doing it explicitly, like this:

gophercloud.AuthOptions{
	IdentityEndpoint: config["identityEndpoint"],
	Username: config["username"],
	Password: config["password"],
	DomainName: config["name"],
	TenantID: config["tenantId"],
	TenantName: config["tenantName"],
}

by accepting "identityEndpoint", you are already diverging from a standard auth options json blob, so being explicit doesn't seem bad.

you are already diverging from a standard auth options json blob, so being explicit doesn't seem bad.

Make sense.