Add Tumblr to the list of supported providers

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationHandlers.Exchange.cs

@@ -342,6 +342,14 @@ public static partial class OpenIddictClientWebIntegrationHandlers
                     context.Response["expires"] = null;
                 }
 
+                // Note: Tumblr returns a non-standard "id_token: false" node that collides
+                // with the standard id_token parameter used in OpenID Connect. To ensure
+                // the response is not rejected, the "id_token" node is manually removed.
+                else if (context.Registration.ProviderType is ProviderTypes.Tumblr)
+                {
+                    context.Response["id_token"] = null;
+                }
+
                 return default;
             }
         }

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationHandlers.Userinfo.cs

@@ -317,6 +317,10 @@ public static partial class OpenIddictClientWebIntegrationHandlers
                         let name = $"{parameter.Key}_{node.Key}"
                         select new KeyValuePair<string, OpenIddictParameter>(name, node.Value)),
 
+                    // Tumblr returns a nested "user" object that is itself nested in a "response" node.
+                    ProviderTypes.Tumblr => new(context.Response["response"]?["user"]?.GetNamedParameters() ??
+                        throw new InvalidOperationException(SR.FormatID0334("response/user"))),
+
                     _ => context.Response
                 };
 

src/OpenIddict.Client.WebIntegration/OpenIddictClientWebIntegrationProviders.xml

@@ -1127,6 +1127,26 @@
     </Environment>
   </Provider>
 
+  <!--
+                                          ▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄
+                                          █▄▄ ▄▄██ ██ ██ ▄▀▄ ██ ▄▄▀██ █████ ▄▄▀██
+                                          ███ ████ ██ ██ █ █ ██ ▄▄▀██ █████ ▀▀▄██
+                                          ███ ████▄▀▀▄██ ███ ██ ▀▀ ██ ▀▀ ██ ██ ██
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+  -->
+
+  <Provider Name="Tumblr" Id="546a1f33-f660-4aa6-9cce-ef950d3ca6f8"
+            Documentation="https://www.tumblr.com/docs/en/api/v2#oauth2-authorization">
+    <Environment Issuer="https://www.tumblr.com/">
+      <Configuration AuthorizationEndpoint="https://www.tumblr.com/oauth2/authorize"
+                     TokenEndpoint="https://api.tumblr.com/v2/oauth2/token"
+                     UserinfoEndpoint="https://api.tumblr.com/v2/user/info">
+        <GrantType Value="authorization_code" />
+        <GrantType Value="refresh_token" />
+      </Configuration>
+    </Environment>
+  </Provider>
+
   <!--
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