docs: update README.md

README.md

@@ -162,7 +162,9 @@ const schemaWithMiddleware = applyMiddleware(schema, yupMiddleware());
 
 ### Setting the Validation Schema of each Mutation
 
-For each mutation that you want to validate the args, you must define a property `validationSchema` when defining it. Example:
+For each mutation that you want to validate the args, you must define the validation schema on the definition of the mutation. The way to do that depends on the version of GraphQL you are using:
+
+#### GraphQL <= 14
 
 ```ts
 const resolvers = {
@@ -178,6 +180,26 @@ const resolvers = {
 };
 ```
 
+#### GraphQL >= 15
+
+```ts
+const resolvers = {
+  // ...
+  Mutation: {
+    AddUser: {
+      extensions: {
+        yupMiddleware: {
+          validationSchema: yupSchemaHere,
+        },
+      },
+      resolve: async (root, args, context, info) => {
+        // ...
+      },
+    },
+  },
+};
+```
+
 You can also pass another property named `validationOptions` to pass
 other [options](#options) that should only be used for this mutation.
 
@@ -195,7 +217,7 @@ export default mutationWithClientMutationId({
       // ...
     }),
   }),
-  mutateAndGetPayload: async args => {
+  mutateAndGetPayload: async (args) => {
     // ...
   },
   outputFields: {
@@ -209,14 +231,15 @@ This will:
 ```js
 const mutation = mutationWithClientMutationId({
   name: 'MyMutation',
-  mutateAndGetPayload: async args => {
+  mutateAndGetPayload: async (args) => {
     // ...
   },
   outputFields: {
     // ...
   },
 });
 
+// GraphQL <= 14
 export default {
   ...mutation,
   validationSchema: yup.object().shape({
@@ -225,6 +248,21 @@ export default {
     }),
   }),
 };
+
+// GraphQL >= 15
+export default {
+  ...mutation,
+  extensions: {
+    ...mutation.extensions,
+    yupMiddleware: {
+      validationSchema: yup.object().shape({
+        input: yup.object().shape({
+          // ...
+        }),
+      }),
+    },
+  },
+};
 ```
 
 [graphql]: https://github.com/graphql/graphql-js