implement federated_credential_flow and workload_identity_creds and add them to the environment_credential

[simon-an]

fixes #1305

[simon-an]

@microsoft-github-policy-service agree

[heaths]

Why does the environment_credential not work? Can we not fix that? In our other languages for Azure SDKs, we have only the environment_credential that works for both user and app registrations.

[simon-an]

Sorry i am not sure what you mean. If you look at the pr, it is implemented in the environment credential. I can rename the pr if that helps :)
Edit: Since this is my first contribution to this repo, i tried to stick as close to the current code as possible.

[heaths]

Sorry i am not sure what you mean. If you look at the pr, it is implemented in the environment credential. I can rename the pr if that helps :) Edit: Since this is my first contribution to this repo, i tried to stick as close to the current code as possible.

You added a public (WorkloadIdentityCredential](https://github.com/Azure/azure-sdk-for-rust/pull/1319/files#diff-2ad4468fd1fd66aac39f9410601f0b67dd7d796bf9a36db12c5b6a87c0b99d35) which we don't need or have in any other language. All support should be internal (however you choose to implement it) to the EnvironmentCredential.

[simon-an]

Sorry i am not sure what you mean. If you look at the pr, it is implemented in the environment credential. I can rename the pr if that helps :) Edit: Since this is my first contribution to this repo, i tried to stick as close to the current code as possible.

You added a public (WorkloadIdentityCredential](https://github.com/Azure/azure-sdk-for-rust/pull/1319/files#diff-2ad4468fd1fd66aac39f9410601f0b67dd7d796bf9a36db12c5b6a87c0b99d35) which we don't need or have in any other language. All support should be internal (however you choose to implement it) to the EnvironmentCredential.

Yes. and what exactly is the problem with that? As far as is see it, the code in this repo is far away from a 1.0 version. So why don't you merge the working contribution and refactor it how you want it to be? I will not look at other language sdks. There are reason why i use rust and contribute (at least try) to the ecosystem. So if you want me to bring this PR in the direction that you want, please direct me to the specifications for the sdks, or describe exactly what you want me to change. (renaming, moving files, etc)

Why is the seperation as a "credentials" not a valid pattern to implement this?
Edit: To be more precise: Implementing the TokenCredential Trait, seams to be realy useful.

[demoray]

First, thank you for the contribution.

While the Azure SDK for Rust is not yet an official SDK, we do our best to follow the Azure SDK development guidelines.

One of the principles we take to heart for this SDK is consistency across all of the SDKs. We would prefer future contributions to consider this and other principles set forth in the above guidelines.