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+# Graph SDK Community Extensions (Graph.Community)
+
+The Graph extension library is a community effort to unblock developers building on .Net Standard who need to call endpoints that are not part of the Microsoft Graph.
+
+[![Build](https://github.com/microsoftgraph/msgraph-sdk-dotnet-contrib/actions/workflows/build.yml/badge.svg?branch=graph-v4&event=push)](https://github.com/microsoftgraph/msgraph-sdk-dotnet-contrib/actions/workflows/build.yml)
+![NuGet package](https://buildstats.info/nuget/Graph.Community)
+
+## Documentation
+
+This community library contains requests and models that extend the Microsoft Graph SDK. Please review the [Roadmap](./docs/ROADMAP.md) for an index of requests that are included and on the roadmap. 
+
+If there is an endpoint node for which you would like a request, please submit an issue to initiate a conversation. This will help reduce wasted effort.
+
+## Getting Started
+
+The library includes a client factory class (`CommunityGraphClientFactory`) that provides methods to setup the Graph Service client with the handlers included in this library.
+
+### Using TokenCredential class
+
+To use a `TokenCredential` class:
+
+```csharp
+var credential = new DefaultAzureCredential();
+
+CommunityGraphClientOptions clientOptions = new CommunityGraphClientOptions()
+{
+  UserAgent = "ExtendedCapabilitiesSample"
+};
+
+var graphServiceClient = CommunityGraphClientFactory.Create(clientOptions, credential);
+```
+
+To use an Authorization provider:
+
+```csharp
+IAuthenticationProvider ap = new CustomAuthenticationProvider(pca, scopes);
+
+CommunityGraphClientOptions clientOptions = new CommunityGraphClientOptions()
+{
+  UserAgent = "ExtendedCapabilitiesSample"
+};
+
+var graphServiceClient = CommunityGraphClientFactory.Create(clientOptions, ap);
+```
+
+A complete implementation is included in the [Diagnostic sample](samples/Diagnostics.cs).
+
+The `CommunityGraphClientOptions` provides for specifing information to [decorate SharePoint REST traffic to help mitigate throttling](https://docs.microsoft.com/en-us/sharepoint/dev/general-development/how-to-avoid-getting-throttled-or-blocked-in-sharepoint-online#how-to-decorate-your-http-traffic-to-avoid-throttling).
+
+Once a GraphServiceClient is instantiated, an extension method provides access to the SharePoint REST endpoint. This `SharePointAPI` extension method requires an absolute URL to the SharePoint site collection that is the target of the call. Subsequent methods of the fluent API are used to address the [feature area of the REST API](https://docs.microsoft.com/en-us/sharepoint/dev/sp-add-ins/determine-sharepoint-rest-service-endpoint-uris).
+
+### Example
+Statement:
+
+```csharp
+gsc.SharePointAPI('https://mock.sharepoint.com/sites/mockSite')
+     .SiteDesigns
+     .Request()
+     .GetAsync()
+```
+
+Request:
+
+```
+GET https://mock.sharepoint.com/sites/mockSite/_api/Microsoft.Sharepoint.Utilities.WebTemplateExtensions.SiteScriptUtility.GetSiteDesigns`
+```
+
+## SharePoint Handler
+
+Starting with v3.21, the library contains middleware (a delegating handler) that will transform errors from SharePoint Online into a ServiceException. This allows consuming code to standardize error handling.
+
+## Breaking change in v3.18
+
+The `SPUser` class returned from the `Web.SiteUsers` request has been renamed to **`User`**. This aligns with the OData.type property returned from the service.
+
+## Versioning
+
+The version number intentionaly aligned with the version of the Microsoft.Graph package. 
+
+
+|Version Component|Notes|
+|-|-|
+|Major|Aligned with Microsoft.Graph|
+|Minor|Aligned with Microsoft.Graph|
+|Patch|Incremented as requests/models are added to Graph.Community|
+|Suffix|Release/build type|
+
+Version suffixes (`#` indicates a sequence number that is reset for each major/minor):
+- `-CI-#` Continuous Integration release built from **dev** branch 
+- `-preview#` Preview release, built from **prerelease** branch
+- No suffix is release build