Add Facebook to the list of supported providers

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationHandlers.cs

@@ -518,10 +518,20 @@ public static partial class OpenIddictClientWebIntegrationHandlers
 
             Debug.Assert(context.UserinfoRequest is not null, SR.GetResourceString(SR.ID4008));
 
+            // Facebook limits the number of fields returned by the userinfo endpoint
+            // but allows returning additional information using special parameters that
+            // determine what fields will be returned as part of the userinfo response.
+            if (context.Registration.ProviderName is Providers.Facebook)
+            {
+                var options = context.Registration.GetFacebookOptions();
+
+                context.UserinfoRequest["fields"] = string.Join(",", options.Fields);
+            }
+
             // By default, LinkedIn returns all the basic fields except the profile image.
             // To retrieve the profile image, a projection parameter must be sent with
             // all the parameters that should be returned from the userinfo endpoint.
-            if (context.Registration.ProviderName is Providers.LinkedIn)
+            else if (context.Registration.ProviderName is Providers.LinkedIn)
             {
                 var options = context.Registration.GetLinkedInOptions();
 

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationProviders.xml

@@ -191,7 +191,7 @@
       As such, the Deezer integration tries to use the standard parameters and only uses the non-standard equivalents
       when no other option exists (e.g an "output" query string parameter must be sent to get JSON token responses).
     -->
-    
+
     <Environment Issuer="https://deezer.com/">
       <Configuration AuthorizationEndpoint="https://connect.deezer.com/oauth/auth.php"
                      TokenEndpoint="https://connect.deezer.com/oauth/access_token.php"
@@ -278,6 +278,32 @@
     <Environment Issuer="https://api.epicgames.dev/epic/oauth/v1" />
   </Provider>
 
+  <!--
+                                      ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
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+                                      ██ ▄▄██ ▀▀ ██ █████ ▄▄▄██ ▄▄▀██ ███ ██ ███ ██ ▄▀███
+                                      ██ ████ ██ ██ ▀▀▄██ ▀▀▀██ ▀▀ ██ ▀▀▀ ██ ▀▀▀ ██ ██ ██
+                                      ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
+  -->
+
+  <Provider Name="Facebook" Documentation="https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow">
+    <Environment Issuer="https://www.facebook.com/">
+      <Configuration AuthorizationEndpoint="https://www.facebook.com/v16.0/dialog/oauth"
+                     TokenEndpoint="https://graph.facebook.com/v16.0/oauth/access_token"
+                     UserinfoEndpoint="https://graph.facebook.com/v16.0/me">
+        <CodeChallengeMethod Value="S256" />
+      </Configuration>
+    </Environment>
+
+    <Setting PropertyName="Fields" ParameterName="fields" Collection="true" Type="String"
+             Description="The fields that should be retrieved from the userinfo endpoint (by default, only basic fields are requested)">
+      <Item Value="email"      Default="true" Required="false" />
+      <Item Value="first_name" Default="true" Required="false" />
+      <Item Value="last_name"  Default="true" Required="false" />
+      <Item Value="name"       Default="true" Required="false" />
+    </Setting>
+  </Provider>
+
   <!--
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