Merge pull request #72 from n9te9/fix/provides-directive-nested-field

fix: provides directive solve nested field

Author: n9te9

_example/ec/apollo/supergraph.graphql

@@ -84,21 +84,32 @@ type Query
   userByEmail(email: String!): User @join__field(graph: USERS)
 }
 
+type Profile
+  @join__type(graph: USERS)
+  @join__type(graph: REVIEWS)
+{
+  displayName: String!
+  avatarUrl: String! @join__field(graph: USERS)
+}
+
 type Review
   @join__type(graph: REVIEWS)
 {
   id: ID!
   body: String!
   authorName: String!
+  author: User @join__field(graph: REVIEWS, provides: "username profile { displayName }")
   product: Product
 }
 
 type User
   @join__type(graph: USERS, key: "id")
   @join__type(graph: USERS, key: "username")
   @join__type(graph: USERS, key: "email")
+  @join__type(graph: REVIEWS, key: "id", extension: true)
 {
-  id: ID!
-  username: String!
-  email: String!
+  id: ID! @join__field(graph: USERS) @join__field(graph: REVIEWS, external: true)
+  username: String! @join__field(graph: USERS) @join__field(graph: REVIEWS, external: true)
+  email: String! @join__field(graph: USERS)
+  profile: Profile! @join__field(graph: USERS) @join__field(graph: REVIEWS, external: true)
 }

_example/ec/reviews/graph/entity.resolvers.go

@@ -6,16 +6,21 @@ interface Node {
   id: ID!
 }
 
+type Profile {
+  displayName: String!
+}
+
 type User @key(fields: "id") {
   id: ID! @external
   username: String! @external
+  profile: Profile! @external
 }
 
 type Review implements Node {
   id: ID!
   body: String!
   authorName: String!
-  author: User @provides(fields: "username")
+  author: User @provides(fields: "username profile { displayName }")
   product: Product @provides(fields: "name price")
 }