feature: support azure MangedIdentity TokenCredential

[Meir017]

closes #558

Tests:

• test managed identity in azure
• Unit tests

[badrishc]

How does this feature work exactly? Is it compatible with the older connection strings? And how does it interface with unit tests?

[Meir017]

How does this feature work exactly?

Assuming the garnet application will run inside of azure (ex: vm / aks) and managed identity will be able to be assigned to the environment

Is it compatible with the older connection strings?

I think this us instead of using a connection string, so any Metadata provided in the connection string will need to be provided in a different way

And how does it interface with unit tests?

We might consider using DefaultAzureCredential https://learn.microsoft.com/en-us/dotnet/api/azure.identity.defaultazurecredential?view=azure-dotnet then for unit tests we could run AZ login in order to populate the AzureCli credential layer

Currently the unit tests don't use the managed identity credential to perform the login

[Meir017]

Somthing that might be concerning, I noticed that the constructor of public AzureStorageNamedDeviceFactory(string serviceUri, TokenCredential credential, ILogger logger = null) is being called multiple times with the exact same argument when starting the server

running locally with

.\bin\Debug\net8.0\GarnetServer.exe "--use-azure-storage" "--storage-managed-identity" "fake-managed-identity" "--storage-service-uri" "https://garnettest.blob.core.windows.net" "--storage-tier" "--logdir" "garnettestcontainer"

called the constructor 5 times, this causes the time until the service prints * Ready to accept connections be to ~20s

created #739

[badrishc]

Somthing that might be concerning, I noticed that the constructor of public AzureStorageNamedDeviceFactory(string serviceUri, TokenCredential credential, ILogger logger = null) is being called multiple times with the exact same argument when starting the server

running locally with

.\bin\Debug\net8.0\GarnetServer.exe "--use-azure-storage" "--storage-managed-identity" "fake-managed-identity" "--storage-service-uri" "https://garnettest.blob.core.windows.net" "--storage-tier" "--logdir" "garnettestcontainer"

called the constructor 5 times, this causes the time until the service prints * Ready to accept connections be to ~20s

created #739

apart from this delay issue, is this PR ready yet?

[Meir017]

apart from this delay issue, is this PR ready yet?

Adding unit tests for managed identity is tricky as they would need to run inside azure (not locally)

Other than that and the conflicts this us ready

[badrishc]

OK. @Meir017, if you could rebase to the latest in main, I think we can go ahead with reviewing and merging this. thank you.

[badrishc]

Somthing that might be concerning, I noticed that the constructor of public AzureStorageNamedDeviceFactory(string serviceUri, TokenCredential credential, ILogger logger = null) is being called multiple times with the exact same argument when starting the server

running locally with

.\bin\Debug\net8.0\GarnetServer.exe "--use-azure-storage" "--storage-managed-identity" "fake-managed-identity" "--storage-service-uri" "https://garnettest.blob.core.windows.net" "--storage-tier" "--logdir" "garnettestcontainer"

called the constructor 5 times, this causes the time until the service prints * Ready to accept connections be to ~20s

created #739

Could you try #970 to see if the startup delay is fixed by this refactor?