feat: public schema from supergraph (#21)

.changeset/curly-ants-march.md

@@ -0,0 +1,8 @@
+---
+'@theguild/federation-composition': minor
+---
+
+Remove `stripFederationFromSupergraph` in favor of `transformSupergraphToPublicSchema`.
+
+Instead of stripping only federation specific types, `transformSupergraphToPublicSchema` yields the
+public api schema as served by the gateway.

__tests__/graphql/transform-supergraph-to-public-schema.spec.ts

@@ -0,0 +1,282 @@
+import { parse, print } from 'graphql';
+import { describe, expect, test } from 'vitest';
+import { transformSupergraphToPublicSchema } from '../../src/graphql/transform-supergraph-to-public-schema';
+
+describe('transformSupergraphToPublicSchema', () => {
+  describe('@inaccessible', () => {
+    test('scalar removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        scalar Scalar1 @inaccessible
+        scalar Scalar2
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot('"scalar Scalar2"');
+    });
+    test('enum removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        enum Enum1 @inaccessible {
+          VALUE1
+          VALUE2
+        }
+        enum Enum2 {
+          VALUE1
+          VALUE2
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "enum Enum2 {
+          VALUE1
+          VALUE2
+        }"
+      `);
+    });
+    test('object type removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        type Object1 @inaccessible {
+          field1: String
+        }
+        type Object2 {
+          field1: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "type Object2 {
+          field1: String
+        }"
+      `);
+    });
+    test('object field removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        type Object {
+          field1: String @inaccessible
+          field2: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "type Object {
+          field2: String
+        }"
+      `);
+    });
+    test('interface type removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        interface Interface1 @inaccessible {
+          field1: String
+        }
+        interface Interface2 {
+          field1: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "interface Interface2 {
+          field1: String
+        }"
+      `);
+    });
+    test('interface field removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        interface Interface {
+          field1: String @inaccessible
+          field2: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "interface Interface {
+          field2: String
+        }"
+      `);
+    });
+    test('union type removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        union Union1 @inaccessible = Type1 | Type2
+        union Union2 = Type1 | Type2
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot('"union Union2 = Type1 | Type2"');
+    });
+    test('object field argument removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        type Object {
+          field1(arg1: String @inaccessible): String
+          field2(arg1: String): String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "type Object {
+          field1: String
+          field2(arg1: String): String
+        }"
+      `);
+    });
+    test('interface field argument removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        interface Object {
+          field1(arg1: String @inaccessible): String
+          field2(arg1: String): String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "interface Object {
+          field1: String
+          field2(arg1: String): String
+        }"
+      `);
+    });
+    test('input object type removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        input Input1 @inaccessible {
+          field1: String
+        }
+        input Input2 {
+          field1: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "input Input2 {
+          field1: String
+        }"
+      `);
+    });
+    test('input object field removal', () => {
+      const sdl = parse(/* GraphQL */ `
+        input Input {
+          field1: String @inaccessible
+          field2: String
+        }
+      `);
+      const resultSdl = transformSupergraphToPublicSchema(sdl);
+      expect(print(resultSdl)).toMatchInlineSnapshot(`
+        "input Input {
+          field2: String
+        }"
+      `);
+    });
+  });
+  test('strips out all federation directives and types', () => {
+    const sdl = parse(/* GraphQL */ `
+      schema
+        @link(url: "https://specs.apollo.dev/link/v1.0")
+        @link(url: "https://specs.apollo.dev/join/v0.3", for: EXECUTION)
+        @link(
+          url: "https://specs.apollo.dev/inaccessible/v0.2"
+          as: "federation__inaccessible"
+          for: SECURITY
+        ) {
+        query: Query
+      }
+
+      directive @federation__inaccessible on FIELD_DEFINITION | OBJECT | INTERFACE | UNION | ARGUMENT_DEFINITION | SCALAR | ENUM | ENUM_VALUE | INPUT_OBJECT | INPUT_FIELD_DEFINITION
+
+      directive @inaccessible on FIELD_DEFINITION | OBJECT | INTERFACE | UNION | ARGUMENT_DEFINITION | SCALAR | ENUM | ENUM_VALUE | INPUT_OBJECT | INPUT_FIELD_DEFINITION
+
+      directive @join__enumValue(graph: join__Graph!) repeatable on ENUM_VALUE
+
+      directive @join__field(
+        graph: join__Graph
+        requires: join__FieldSet
+        provides: join__FieldSet
+        type: String
+        external: Boolean
+        override: String
+        usedOverridden: Boolean
+      ) repeatable on FIELD_DEFINITION | INPUT_FIELD_DEFINITION
+
+      directive @join__graph(name: String!, url: String!) on ENUM_VALUE
+
+      directive @join__implements(
+        graph: join__Graph!
+        interface: String!
+      ) repeatable on OBJECT | INTERFACE
+
+      directive @join__type(
+        graph: join__Graph!
+        key: join__FieldSet
+        extension: Boolean! = false
+        resolvable: Boolean! = true
+        isInterfaceObject: Boolean! = false
+      ) repeatable on OBJECT | INTERFACE | UNION | ENUM | INPUT_OBJECT | SCALAR
+
+      directive @join__unionMember(graph: join__Graph!, member: String!) repeatable on UNION
+
+      directive @link(
+        url: String
+        as: String
+        for: link__Purpose
+        import: [link__Import]
+      ) repeatable on SCHEMA
+
+      scalar join__FieldSet
+
+      enum join__Graph {
+        BRRT @join__graph(name: "brrt", url: "http://localhost/graphql")
+        BUBUBU @join__graph(name: "bububu", url: "http://localhost:1/graphql")
+      }
+
+      scalar link__Import
+
+      enum link__Purpose {
+        SECURITY
+
+        EXECUTION
+      }
+
+      type Query @join__type(graph: BRRT) @join__type(graph: BUBUBU) {
+        foo: Int! @join__field(graph: BRRT)
+        ok1: Int! @join__field(graph: BRRT)
+        a: String! @join__field(graph: BUBUBU)
+        oi: Type2 @federation__inaccessible @join__field(graph: BUBUBU)
+      }
+
+      type Type2
+        @join__type(graph: BRRT, key: "id", extension: true)
+        @join__type(graph: BUBUBU, key: "id") {
+        id: ID! @federation__inaccessible
+        inStock: Boolean! @join__field(graph: BRRT)
+        field1: String! @federation__inaccessible @join__field(graph: BUBUBU)
+      }
+    `);
+
+    const resultSdl = transformSupergraphToPublicSchema(sdl);
+    expect(print(resultSdl)).toMatchInlineSnapshot(`
+      "type Query {
+        foo: Int!
+        ok1: Int!
+        a: String!
+      }
+
+      type Type2 {
+        inStock: Boolean!
+      }"
+    `);
+  });
+  test('graphql specification directives are omitted from the SDL', () => {
+    const sdl = parse(/* GraphQL */ `
+      directive @skip(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+      directive @include(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+      directive @deprecated(reason: String = "No longer supported") on FIELD_DEFINITION | ENUM_VALUE
+    `);
+    const resultSdl = transformSupergraphToPublicSchema(sdl);
+    expect(print(resultSdl)).toMatchInlineSnapshot('""');
+  });
+  test('does not omit @deprecated directive', () => {
+    const sdl = parse(/* GraphQL */ `
+      type Query {
+        foo: String @deprecated(reason: "jooo")
+      }
+    `);
+    const resultSdl = transformSupergraphToPublicSchema(sdl);
+    expect(print(resultSdl)).toMatchInlineSnapshot(`
+      "type Query {
+        foo: String @deprecated(reason: \\"jooo\\")
+      }"
+    `);
+  });
+});

src/graphql/helpers.ts

@@ -1,72 +1,5 @@
-import {
-  DefinitionNode,
-  DirectiveDefinitionNode,
-  DocumentNode,
-  Kind,
-  specifiedDirectives,
-  visit,
-} from 'graphql';
+import { Kind, type DefinitionNode, type DirectiveDefinitionNode } from 'graphql';
 
 export function isDirectiveDefinition(node: DefinitionNode): node is DirectiveDefinitionNode {
   return node.kind === Kind.DIRECTIVE_DEFINITION;
 }
-
-export function stripFederationFromSupergraph(supergraph: DocumentNode) {
-  function removeDirective(node: {
-    name: {
-      value: string;
-    };
-  }) {
-    const directiveName = node.name.value;
-    const isSpecifiedDirective = specifiedDirectives.some(d => d.name === directiveName);
-    if (!isSpecifiedDirective) {
-      const isFederationDirective =
-        directiveName === 'link' ||
-        directiveName === 'inaccessible' ||
-        directiveName === 'tag' ||
-        directiveName === 'join__graph' ||
-        directiveName === 'join__type' ||
-        directiveName === 'join__implements' ||
-        directiveName === 'join__unionMember' ||
-        directiveName === 'join__enumValue' ||
-        directiveName === 'join__field';
-
-      if (isFederationDirective) {
-        return null;
-      }
-    }
-  }
-
-  return visit(supergraph, {
-    DirectiveDefinition: removeDirective,
-    Directive: removeDirective,
-    SchemaDefinition() {
-      return null;
-    },
-    SchemaExtension() {
-      return null;
-    },
-    EnumTypeDefinition: node => {
-      if (
-        node.name.value === 'core__Purpose' ||
-        node.name.value === 'join__Graph' ||
-        node.name.value === 'link__Purpose'
-      ) {
-        return null;
-      }
-
-      return node;
-    },
-    ScalarTypeDefinition: node => {
-      if (
-        node.name.value === '_FieldSet' ||
-        node.name.value === 'link__Import' ||
-        node.name.value === 'join__FieldSet'
-      ) {
-        return null;
-      }
-
-      return node;
-    },
-  });
-}