Supergraph Handler (#5744)

* Go

* chore(dependencies): updated changesets for modified dependencies

* Cleanup

* Go

* Do not do batching for a single subschema

* Go

* Trigger

* Fix dependenceis

* chore(dependencies): updated changesets for modified dependencies

---------

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

.changeset/@graphql-mesh_graphql-5744-dependencies.md

@@ -0,0 +1,6 @@
+---
+"@graphql-mesh/graphql": patch
+---
+dependencies updates:
+  - Added dependency [`@graphql-tools/federation@^1.1.0` ↗︎](https://www.npmjs.com/package/@graphql-tools/federation/v/1.1.0) (to `dependencies`)
+  - Removed dependency [`@graphql-tools/wrap@^10.0.0` ↗︎](https://www.npmjs.com/package/@graphql-tools/wrap/v/10.0.0) (from `dependencies`)

.changeset/@graphql-mesh_merger-stitching-5744-dependencies.md

@@ -0,0 +1,5 @@
+---
+"@graphql-mesh/merger-stitching": patch
+---
+dependencies updates:
+  - Removed dependency [`@graphql-tools/stitching-directives@^3.0.0` ↗︎](https://www.npmjs.com/package/@graphql-tools/stitching-directives/v/3.0.0) (from `dependencies`)

.changeset/@graphql-mesh_runtime-5744-dependencies.md

@@ -0,0 +1,5 @@
+---
+"@graphql-mesh/runtime": patch
+---
+dependencies updates:
+  - Removed dependency [`@graphql-tools/batch-execute@^9.0.0` ↗︎](https://www.npmjs.com/package/@graphql-tools/batch-execute/v/9.0.0) (from `dependencies`)

.changeset/ninety-llamas-live.md

@@ -0,0 +1,6 @@
+---
+'@graphql-mesh/merger-stitching': patch
+'@graphql-mesh/graphql': patch
+---
+
+New strategy to handle Federation

.changeset/three-toes-shave.md

@@ -0,0 +1,6 @@
+---
+'@graphql-mesh/supergraph': patch
+'@graphql-mesh/types': patch
+---
+
+New Supergraph handler

examples/federation-example/gateway-supergraph/.meshrc.yml

@@ -0,0 +1,11 @@
+sources:
+  - name: Supergraph
+    handler:
+      supergraph:
+        source: ./supergraph.graphql
+
+documents:
+  - example-query.graphql
+
+serve:
+  playground: true

examples/federation-example/gateway-supergraph/example-query.graphql

@@ -0,0 +1,58 @@
+fragment User on User {
+  id
+  username
+  name
+}
+
+fragment Review on Review {
+  id
+  body
+}
+
+fragment Product on Product {
+  inStock
+  name
+  price
+  shippingEstimate
+  upc
+  weight
+}
+
+query TestQuery {
+  users {
+    ...User
+    reviews {
+      ...Review
+      product {
+        ...Product
+        reviews {
+          ...Review
+          author {
+            ...User
+            reviews {
+              ...Review
+              product {
+                ...Product
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  topProducts {
+    ...Product
+    reviews {
+      ...Review
+      author {
+        ...User
+        reviews {
+          ...Review
+          product {
+            ...Product
+          }
+        }
+      }
+    }
+  }
+}

examples/federation-example/gateway-supergraph/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "federation-supergraph-gateway",
+  "version": "0.0.0",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "@graphql-mesh/cli": "0.86.0",
+    "@graphql-mesh/supergraph": "0.0.0",
+    "graphql": "16.7.1"
+  }
+}

examples/federation-example/gateway-supergraph/supergraph.graphql

@@ -0,0 +1,78 @@
+schema
+  @core(feature: "https://specs.apollo.dev/core/v0.2")
+  @core(feature: "https://specs.apollo.dev/join/v0.1", for: EXECUTION) {
+  query: Query
+}
+
+directive @core(as: String, feature: String!, for: core__Purpose) repeatable on SCHEMA
+
+directive @join__field(
+  graph: join__Graph
+  provides: join__FieldSet
+  requires: join__FieldSet
+) on FIELD_DEFINITION
+
+directive @join__graph(name: String!, url: String!) on ENUM_VALUE
+
+directive @join__owner(graph: join__Graph!) on INTERFACE | OBJECT
+
+directive @join__type(graph: join__Graph!, key: join__FieldSet) repeatable on INTERFACE | OBJECT
+
+type Product
+  @join__owner(graph: PRODUCTS)
+  @join__type(graph: PRODUCTS, key: "upc")
+  @join__type(graph: INVENTORY, key: "upc")
+  @join__type(graph: REVIEWS, key: "upc") {
+  inStock: Boolean @join__field(graph: INVENTORY)
+  name: String @join__field(graph: PRODUCTS)
+  price: Int @join__field(graph: PRODUCTS)
+  reviews: [Review] @join__field(graph: REVIEWS)
+  shippingEstimate: Int @join__field(graph: INVENTORY, requires: "price weight")
+  upc: String! @join__field(graph: PRODUCTS)
+  weight: Int @join__field(graph: PRODUCTS)
+}
+
+type Query {
+  me: User @join__field(graph: ACCOUNTS)
+  topProducts(first: Int = 5): [Product] @join__field(graph: PRODUCTS)
+  user(id: ID!): User @join__field(graph: ACCOUNTS)
+  users: [User] @join__field(graph: ACCOUNTS)
+}
+
+type Review @join__owner(graph: REVIEWS) @join__type(graph: REVIEWS, key: "id") {
+  author: User @join__field(graph: REVIEWS, provides: "username")
+  body: String @join__field(graph: REVIEWS)
+  id: ID! @join__field(graph: REVIEWS)
+  product: Product @join__field(graph: REVIEWS)
+}
+
+type User
+  @join__owner(graph: ACCOUNTS)
+  @join__type(graph: ACCOUNTS, key: "id")
+  @join__type(graph: REVIEWS, key: "id") {
+  id: ID! @join__field(graph: ACCOUNTS)
+  name: String @join__field(graph: ACCOUNTS)
+  reviews: [Review] @join__field(graph: REVIEWS)
+  username: String @join__field(graph: ACCOUNTS)
+}
+
+enum core__Purpose {
+  """
+  `EXECUTION` features provide metadata necessary to for operation execution.
+  """
+  EXECUTION
+
+  """
+  `SECURITY` features provide metadata necessary to securely resolve fields.
+  """
+  SECURITY
+}
+
+scalar join__FieldSet
+
+enum join__Graph {
+  ACCOUNTS @join__graph(name: "accounts", url: "http://localhost:9880/graphql")
+  INVENTORY @join__graph(name: "inventory", url: "http://localhost:9872/graphql")
+  PRODUCTS @join__graph(name: "products", url: "http://localhost:9873/graphql")
+  REVIEWS @join__graph(name: "reviews", url: "http://localhost:9874/graphql")
+}

examples/federation-example/gateway-supergraph/supergraph.yaml

@@ -0,0 +1,17 @@
+subgraphs:
+  accounts:
+    routing_url: http://localhost:9880/graphql
+    schema:
+      file: ../services/accounts-subgraph/typeDefs.graphql
+  reviews:
+    routing_url: http://localhost:9874/graphql
+    schema:
+      file: ../services/reviews/typeDefs.graphql
+  products:
+    routing_url: http://localhost:9873/graphql
+    schema:
+      file: ../services/products/typeDefs.graphql
+  inventory:
+    routing_url: http://localhost:9872/graphql
+    schema:
+      file: ../services/inventory/typeDefs.graphql

examples/federation-example/package.json

@@ -12,6 +12,7 @@
     "start-gateway": "mesh dev --dir gateway",
     "start-gateway-delayed": "delay 1 && npm run start-gateway",
     "start-service-accounts": "ts-node services/accounts/index.ts",
+    "start-service-accounts-subgraph": "ts-node services/accounts-subgraph/index.ts",
     "start-service-inventory": "ts-node services/inventory/index.ts",
     "start-service-products": "ts-node services/products/index.ts",
     "start-service-reviews": "ts-node services/reviews/index.ts",

examples/federation-example/services/accounts-subgraph/index.ts

@@ -0,0 +1,6 @@
+import { accountsSubgraphServer } from './server';
+
+accountsSubgraphServer().catch(error => {
+  console.error(error);
+  process.exit(1);
+});

examples/federation-example/services/accounts-subgraph/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "accounts-subgraph",
+  "version": "0.0.0",
+  "license": "MIT",
+  "private": true,
+  "scripts": {
+    "start": "ts-node index.ts"
+  },
+  "dependencies": {
+    "@apollo/subgraph": "2.5.1",
+    "apollo-server": "3.12.0",
+    "graphql": "16.7.1",
+    "ts-node": "10.9.1",
+    "typescript": "5.1.6"
+  }
+}

examples/federation-example/services/accounts-subgraph/server.ts

@@ -0,0 +1,71 @@
+import { ApolloServer, gql } from 'apollo-server';
+import { buildSubgraphSchema } from '@apollo/subgraph';
+
+const typeDefs = gql`
+  extend type Query {
+    me: User
+    user(id: ID!): User
+    users: [User]
+  }
+
+  type User @key(fields: "id") {
+    id: ID!
+    name: String
+    username: String
+  }
+`;
+
+const resolvers = {
+  User: {
+    __resolveReference(object, context) {
+      return {
+        ...object,
+        ...context.users.find(user => user.id === object.id),
+      };
+    },
+  },
+  Query: {
+    me(_root, _args, context) {
+      return context.users[0];
+    },
+    users(_root, _args, context) {
+      return context.users;
+    },
+    user(_root, args, context) {
+      return context.users.find(user => user.id === args.id);
+    },
+  },
+};
+
+const server = new ApolloServer({
+  schema: buildSubgraphSchema([
+    {
+      typeDefs,
+      resolvers,
+    },
+  ]),
+  context: {
+    users: [
+      {
+        id: '1',
+        name: 'Ada Lovelace',
+        birthDate: '1815-12-10',
+        username: '@ada',
+      },
+      {
+        id: '2',
+        name: 'Alan Turing',
+        birthDate: '1912-06-23',
+        username: '@complete',
+      },
+    ],
+  },
+});
+
+export const accountsSubgraphServer = () =>
+  server.listen({ port: 9880 }).then(({ url }) => {
+    if (!process.env.CI) {
+      console.log(`🚀 Server ready at ${url}`);
+    }
+    return server;
+  });

examples/federation-example/services/accounts-subgraph/typeDefs.graphql

@@ -0,0 +1,11 @@
+extend type Query {
+  me: User
+  user(id: ID!): User
+  users: [User]
+}
+
+type User @key(fields: "id") {
+  id: ID!
+  name: String
+  username: String
+}

examples/federation-example/services/inventory/server.ts

@@ -1,3 +1,4 @@
+import { inspect } from 'node:util';
 import { ApolloServer, gql } from 'apollo-server';
 import { buildSubgraphSchema } from '@apollo/subgraph';
 
@@ -20,6 +21,9 @@ const resolvers = {
       };
     },
     shippingEstimate(object) {
+      if (object.price == null || object.weight == null) {
+        throw new Error(`${inspect(object)} doesn't have required fields; "price" and "weight".`);
+      }
       // free for expensive items
       if (object.price > 1000) return 0;
       // estimate is based on weight

examples/federation-example/services/inventory/typeDefs.graphql

@@ -0,0 +1,7 @@
+extend type Product @key(fields: "upc") {
+  upc: String! @external
+  weight: Int @external
+  price: Int @external
+  inStock: Boolean
+  shippingEstimate: Int @requires(fields: "price weight")
+}

examples/federation-example/services/products/typeDefs.graphql

@@ -0,0 +1,10 @@
+extend type Query {
+  topProducts(first: Int = 5): [Product]
+}
+
+type Product @key(fields: "upc") {
+  upc: String!
+  name: String
+  price: Int
+  weight: Int
+}

examples/federation-example/services/reviews/typeDefs.graphql

@@ -0,0 +1,17 @@
+type Review @key(fields: "id") {
+  id: ID!
+  body: String
+  author: User @provides(fields: "username")
+  product: Product
+}
+
+extend type User @key(fields: "id") {
+  id: ID! @external
+  username: String @external
+  reviews: [Review]
+}
+
+extend type Product @key(fields: "upc") {
+  upc: String! @external
+  reviews: [Review]
+}