Add API docs for rootValue

apollographql · Aug 21, 2018 · ecbe10a · ecbe10a
1 parent 7243787
commit ecbe10a
Showing 1 changed file with 15 additions and 0 deletions.
diff --git a/docs/source/api/apollo-server.md b/docs/source/api/apollo-server.md
@@ -51,6 +51,21 @@ new ApolloServer({
 		authScope: getScope(req.headers.authorization)
 	}),
 });
+```
+
+  * `rootValue`: <`Any`> | <`Function`>
+
+    A value or function called with the parsed `Document`, creating the root value passed to the graphql executor. The function is useful if you wish to provide a different root value based on the query operation type.
+
+```js
+new ApolloServer({
+  typeDefs,
+  resolvers,
+  rootValue: (documentAST) => ({
+    const op = getOperationAST(documentNode)
+    return op === 'mutation' ? mutationRoot : queryRoot;
+  })
+});
 ```
 
 * `mocks`: <`Object`> | <`Boolean`>