Request Context With Middleware Options

[peombwa]

Fixes issue #362

Changes proposed in this pull request

Adds middleware options

Customers can pass configuration options to middleware handlers using a set of pre-configured IBaseRequest extension methods to alter the handlers behaviour per request.

HttpProvider httpProvider = new HttpProvider();

var graphClient = new GraphServiceClient(appOnlyProvider, httpProvider);
graphClient.PerRequestAuthProvider = () => CreateDelegatedProvider();

var me = await graphClient.Me.Request()
.WithScopes(string [] { "User.Read" }) // adds auth scopes & is defined by the auth provider
.WithMaxRetry(5) // specifies maximum number of retries & is defined by the auth provider
.WithPerRequestAuthProvider() // configures the per request auth provider for this single request
.GetAsync();

Adds ability to set feature flags to http client's default headers

this.httpClient.SetFeatureFlags(FeatureFlag.RedirectHandler | FeatureFlag.RetryHandler | FeatureFlag.AuthHandler | FeatureFlag.DefaultHttpProvider);

Adds IAuthProviderOption interface

The IAuthProviderOption will be used by the auth providers to set provider specific options as part of the request.
The auth providers will expose and extension method to IBaseRequest which sets the options it needs e.g.

.WithScopes(scopes)
.WithUser(UserAccount)

Adds a RequestContext object that's set on HttpRequestMessage property bag with every request

The request context contains :

• Middleware options map
• Client request id
• Cancelation Token
• FeatureUsage flags

Other links

• Request context design https://github.com/microsoftgraph/msgraph-sdk-design/blob/master/middleware/RequestContext.md

[MIchaelMainer]

Two changes:

• Change FeatureFlgs to enum flags
• Make sure that customer set ClientRequestId always win regardless of when it is set (see comments)/

[darrelmiller]

Using .WithAuthProvider(delegateOnlyProvider) is good if you are in an environment where you have access to the AuthProvider instance. However, in a WebApp controller you may not want to add the complexity of injecting in the AuthProvider instance into the controller.

Would it make sense to do something like this?

HttpProvider httpProvider = new HttpProvider();

var graphClient = new GraphServiceClient(appOnlyProvider, httpProvider);
graphClient.PerRequestAuthProvider = () => CreateDelegatedProvider();

var me = await graphClient.Me.Request()
.WithScopes(string [] { "User.Read" }) // adds auth scopes
.WithMaxRetry(5) // specifies maximum number of retries
.WithPerRequestAuthProvider()
.GetAsync();

This would allow the graphClient instance to be created in Startup, configured and the .WithPerRequestAuthProvider() can get the instance of the AuthProvider.

[Misiu]

I'm aware that this is an old issue, but for someone like me, everything related to MS Graph is new.
I'm trying to use Graph in Windows Service to send mail.
Because this repo is for bugs and feature requests I've created a question on SO: https://stackoverflow.com/questions/55571720/correct-way-to-create-confidentialclientapplication-that-allows-retry-for-window.
I'll be grateful if You guys could take a look.

Currently this repo don't have any examples provided. Can we ask for creating them (can we create issues for that)?

[michael-hawker]

@peombwa looks like WithScopes wasn't implemented though it's in all the examples here? Was this an oversight or should a new issue be filed?

[darrelmiller]

For anyone else looking, it is over here https://github.com/microsoftgraph/msgraph-sdk-dotnet-auth/blob/ae832dfc319f1fa06732cf0e7cadc133ddefbd93/src/Microsoft.Graph.Auth/Extensions/BaseRequestExtensions.cs