wundergraph · Aenimus · Aug 25, 2023 · Aug 25, 2023
diff --git a/composition/src/errors/errors.ts b/composition/src/errors/errors.ts
@@ -181,7 +181,7 @@ export function shareableFieldDefinitionsError(parent: ObjectContainer, children
     }
     if (shareableSubgraphs.length < 1) {
       errorMessages.push(
-        `\n The field "${fieldName}" is defined in the following subgraphs: "${shareableSubgraphs.join('", "')}".` +
+        `\n The field "${fieldName}" is defined in the following subgraphs: "${[...field.subgraphs].join('", "')}".` +
         `\n However, it it is not declared "@shareable" in any of them.`,
       );
     } else {
@@ -571,4 +571,12 @@ export function invalidArgumentsError(fieldPath: string, invalidArguments: Inval
       `", which is not a valid input type.\n`;
   }
   return new Error(message);
-}
+}
+
+export const noQueryRootTypeError = new Error(
+    `A valid federated graph must have at least one populated query root type.\n` +
+  ` For example:\n` +
+  `  type Query {\n` +
+  `    dummy: String\n` +
+  `  }`
+);
diff --git a/composition/src/federation/federation-factory.ts b/composition/src/federation/federation-factory.ts
@@ -72,6 +72,7 @@ import {
   invalidUnionError,
   minimumSubgraphRequirementError,
   noBaseTypeExtensionError,
+  noQueryRootTypeError,
   shareableFieldDefinitionsError,
   subgraphValidationError,
   subgraphValidationFailureErrorMessage,
@@ -101,6 +102,7 @@ import {
   DEFAULT_SUBSCRIPTION,
   FIELD_NAME,
   INLINE_FRAGMENT,
+  QUERY,
 } from '../utils/string-constants';
 import {
   doSetsHaveAnyOverlap,
@@ -1134,6 +1136,9 @@ export class FederationFactory {
       container.node.interfaces = this.getAndValidateImplementedInterfaces(container);
       definitions.push(container.node);
     }
+    if (!this.parentMap.has(QUERY)) {
+      this.errors.push(noQueryRootTypeError);
+    }
     if (this.errors.length > 0) {
       return { errors: this.errors };
     }

diff --git a/composition/tests/arguments.test.ts b/composition/tests/arguments.test.ts
@@ -25,12 +25,16 @@ describe('Argument federation tests', () => {
       subgraphWithArgument('subgraph-b', 'String'),
     ]);
     expect(errors).toBeUndefined();
-    expect(documentNodeToNormalizedString(federationResult.federatedGraphAST)).toBe(
+    expect(documentNodeToNormalizedString(federationResult!.federatedGraphAST)).toBe(
       normalizeString(
-        versionTwoBaseSchema +
-          `type Object {
-        field(input: String): String
-      }
+        versionTwoBaseSchema + `
+            type Query {
+              dummy: String!
+            }
+
+            type Object {
+              field(input: String): String
+            }
     `,
       ),
     );
@@ -44,10 +48,14 @@ describe('Argument federation tests', () => {
     expect(errors).toBeUndefined();
     expect(documentNodeToNormalizedString(federationResult!.federatedGraphAST)).toBe(
       normalizeString(
-        versionTwoBaseSchema +
-          `type Object {
-        field(input: Float!): String
-      }
+        versionTwoBaseSchema + `
+        type Query {
+          dummy: String!
+        }
+
+        type Object {
+          field(input: Float!): String
+        }
     `,
       ),
     );
@@ -59,12 +67,16 @@ describe('Argument federation tests', () => {
       subgraphWithArgumentAndDefaultValue('subgraph-b', 'Int', '1337'),
     ]);
     expect(errors).toBeUndefined();
-    expect(documentNodeToNormalizedString(federationResult.federatedGraphAST)).toBe(
+    expect(documentNodeToNormalizedString(federationResult!.federatedGraphAST)).toBe(
       normalizeString(
-        versionTwoBaseSchema +
-          `type Object {
-        field(input: Int): String
-      }
+        versionTwoBaseSchema + `
+        type Query {
+          dummy: String!
+        }
+
+        type Object {
+          field(input: Int): String
+        }
     `,
       ),
     );
@@ -78,10 +90,14 @@ describe('Argument federation tests', () => {
     expect(errors).toBeUndefined();
     expect(documentNodeToNormalizedString(federationResult!.federatedGraphAST)).toBe(
       normalizeString(
-        versionTwoBaseSchema +
-          `type Object {
-        field(input: Boolean = false): String
-      }
+        versionTwoBaseSchema + `
+        type Query {
+          dummy: String!
+        }
+
+        type Object {
+          field(input: Boolean = false): String
+        }
     `,
       ),
     );
@@ -144,6 +160,10 @@ describe('Argument federation tests', () => {
       interface Interface {
         field(requiredInAll: Int!, requiredOrOptionalInAll: String!, optionalInAll: Boolean): String
       }
+
+      type Query {
+        dummy: String!
+      }
 
       type Object implements Interface {
         field(requiredInAll: Int!, requiredOrOptionalInAll: String!, optionalInAll: Boolean): String
@@ -225,6 +245,10 @@ const subgraphWithArgument = (name: string, typeName: string): Subgraph => ({
   name,
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String! @shareable
+    }
+
     type Object @shareable {
       field(input: ${typeName}): String
     }
@@ -235,6 +259,10 @@ const subgraphWithArgumentAndDefaultValue = (name: string, typeName: string, def
   name,
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String! @shareable
+    }
+
     type Object @shareable {
       field(input: ${typeName} = ${defaultValue}): String
     }
@@ -245,6 +273,10 @@ const subgraphA = {
   name: 'subgraph-a',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String! @shareable
+    }
+
     interface Interface {
       field(requiredInAll: Int!, requiredOrOptionalInAll: String!, optionalInAll: Boolean, optionalInSome: Float): String
     }

diff --git a/composition/tests/entities.test.ts b/composition/tests/entities.test.ts
@@ -10,8 +10,11 @@ describe('Entities federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionOneBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       type Trainer {
         id: Int!
         details: Details!
@@ -38,8 +41,12 @@ describe('Entities federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionOneBaseSchema + `
+      type Query {
+        dummy: String!
+        trainer: Trainer!
+      }
+
       type Trainer {
         id: Int!
         details: Details!
@@ -51,10 +58,6 @@ describe('Entities federation tests', () => {
         age: Int!
       }
 
-      type Query {
-        trainer: Trainer!
-      }
-
       type Pokemon {
         name: String!
         level: Int!
@@ -167,8 +170,7 @@ describe('Entities federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST!;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionOneBaseSchema + `
       type Trainer {
         id: Int!
         pokemon: [Pokemon!]!
@@ -179,6 +181,10 @@ describe('Entities federation tests', () => {
         name: String!
         level: Int!
       }
+
+      type Query {
+        dummy: String!
+      }
 
       type Details {
         name: String!
@@ -194,6 +200,10 @@ const subgraphA: Subgraph = {
   name: 'subgraph-a',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String!
+    }
+
     type Trainer @key(fields: "id") {
       id: Int!
       details: Details!
@@ -296,6 +306,10 @@ const subgraphG: Subgraph = {
   name: 'subgraph-g',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String!
+    }
+
     extend type Trainer @key(fields: "id") {
       id: Int!
       details: Details!

diff --git a/composition/tests/enums.test.ts b/composition/tests/enums.test.ts
@@ -1,7 +1,7 @@
 import { federateSubgraphs, incompatibleSharedEnumError, Subgraph } from '../src';
 import { parse } from 'graphql';
 import { describe, expect, test } from 'vitest';
-import { documentNodeToNormalizedString, normalizeString, versionOneBaseSchema } from './utils/utils';
+import { documentNodeToNormalizedString, normalizeString, versionTwoBaseSchema } from './utils/utils';
 
 describe('Enum federation tests', () => {
   const parentName = 'Instruction';
@@ -12,8 +12,11 @@ describe('Enum federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionTwoBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       enum Instruction {
         FIGHT
         POKEMON
@@ -31,8 +34,11 @@ describe('Enum federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionTwoBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       enum Instruction {
         FIGHT
         POKEMON
@@ -52,8 +58,11 @@ describe('Enum federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionTwoBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       enum Instruction {
         FIGHT
       }
@@ -69,11 +78,13 @@ describe('Enum federation tests', () => {
   test('that enums must be consistent if used as both an input and output', () => {
     const { errors, federationResult } = federateSubgraphs([subgraphC, subgraphD]);
     expect(errors).toBeUndefined();
-    const federatedGraph = federationResult!.federatedGraphAST;
-    expect(documentNodeToNormalizedString(federatedGraph)).toBe(
+    expect(documentNodeToNormalizedString(federationResult!.federatedGraphAST)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionTwoBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       enum Instruction {
         FIGHT
         POKEMON
@@ -103,6 +114,10 @@ const subgraphA: Subgraph = {
   name: 'subgraph-a',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String! @shareable
+    }
+
     enum Instruction {
       FIGHT
       POKEMON
@@ -125,6 +140,10 @@ const subgraphC = {
   name: 'subgraph-c',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String! @shareable
+    }
+
     enum Instruction {
       FIGHT
       POKEMON

diff --git a/composition/tests/inputs.test.ts b/composition/tests/inputs.test.ts
@@ -10,8 +10,11 @@ describe('Input federation tests', () => {
     const federatedGraph = federationResult!.federatedGraphAST;
     expect(documentNodeToNormalizedString(federatedGraph)).toBe(
       normalizeString(
-        versionOneBaseSchema +
-          `
+        versionOneBaseSchema + `
+      type Query {
+        dummy: String!
+      }
+
       input TechnicalMachine {
         move: String!
         number: Int!
@@ -35,6 +38,10 @@ const subgraphA: Subgraph = {
   name: 'subgraph-a',
   url: '',
   definitions: parse(`
+    type Query {
+      dummy: String!
+    }
+
     input TechnicalMachine {
       move: String!
       number: Int!