The `from_environment` function in
`ApplicationDefaultCredentialsAuthenticator` had an `unwrap` call on an
io::Result after reading the service account key from file. File
operations are inherently fallible, and panicking on such a failure is
generally a bad convention compared to propagating the IO error.
Propagating that error from the `from_environment` function is not
practical however, because the returned Result type does not include IO
errors, and changing the function signature would be semver
incompatible.
This change instead defers reading the key file to a later function
call. Now `from_environment` only reads the value of the
`GOOGLE_APPLICATION_CREDENTIALS` into a PathBuf, and a later call to
`ServiceAccountFlow::new` will actually read the file. That constructor
already returns an io::Result, so folding the read error into it is
possible, and none of the changes impact public items so it's all
semver-compatible.
For google stuff these are relevant when trying to invoke e.g. Cloud
Run services. I'm not at all knowledgeable enough with OAuth to be able
to tell if what I'm doing here is correct.
This is a breaking change. `AccessToken` got renamed to just `Token`
(since it now encompasses more than just `access_token` and there are
some changes to the `TokenInfo` type too.
Sponsored by: standard.ai
This adjusts the code and documentation for `--all-features` and
`--no-default-features` to work correctly. With `--no-default-features`
no `DefaultAuthenticator` is made available. Users are in control of
picking the `Connector` they want to use, and are not forced to stomach
a dependency on `rustls` or `hyper-tls` if their TLS implementation of
choice doesn't happen to match one of the two.
To indicate this, the unstable `doc_cfg` feature is used to build
documentation on docs.rs. That way the generated documentation has
notices on these types that look as such:
> This is supported on crate features hyper-rustls or hyper-tls only.
Additionally this functionality is tested via additional coverage in the
Actions' CI.
