apollo-federation 2.15.0

Apollo Federation
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
use apollo_federation::subgraph::typestate::Subgraph;
use insta::assert_snapshot;

use super::ServiceDefinition;
use super::compose;
use super::compose_as_fed2_subgraphs;
use super::print_sdl;

// =============================================================================
// MISCELLANEOUS COMPOSITION TESTS - Standalone composition behavior tests
// =============================================================================

/// `{}` on inputs with required fields must not appear on the composed supergraph (matches
/// graphql-js `printSchema` behavior). Valid `{}` on all-optional inputs is kept when all
/// subgraphs agree; see `misc_drops_empty_object_default_when_only_some_subgraphs_declare_it`.
#[test]
fn misc_strips_invalid_empty_object_argument_defaults_on_supergraph() {
    let subgraph = ServiceDefinition {
        name: "subgraph",
        type_defs: r#"
        type Query {
          fieldA(filter: InputWithRequired = {}): String
          fieldB(filter: InputAllOptional = {}): String
        }

        input InputWithRequired {
          requiredA: String!
          requiredB: String!
          requiredC: String!
        }

        input InputAllOptional {
          optionalField: String
        }
        "#,
    };

    let supergraph = compose_as_fed2_subgraphs(&[subgraph]).expect("composition should succeed");
    let sdl = print_sdl(supergraph.schema().schema());

    assert!(
        !sdl.contains("filter: InputWithRequired = {}"),
        "supergraph should omit invalid empty-object default when input has required fields, got:\n{sdl}"
    );
    assert!(
        sdl.contains("filter: InputAllOptional = {}"),
        "supergraph should keep valid empty-object default when all input fields are optional, got:\n{sdl}"
    );
}

#[test]
fn misc_drops_empty_object_default_when_only_some_subgraphs_declare_it() {
    let with_default = ServiceDefinition {
        name: "withDefault",
        type_defs: r#"
        type Query {
          q: Int @shareable
        }

        type Thing @shareable {
          f(filter: InputAllOptional = {}): String
        }

        input InputAllOptional {
          optionalField: String
        }
        "#,
    };
    let without_default = ServiceDefinition {
        name: "withoutDefault",
        type_defs: r#"
        type Query {
          q: Int @shareable
        }

        type Thing @shareable {
          f(filter: InputAllOptional): String
        }

        input InputAllOptional {
          optionalField: String
        }
        "#,
    };

    let supergraph = compose_as_fed2_subgraphs(&[with_default, without_default])
        .expect("composition should succeed");
    let sdl = print_sdl(supergraph.schema().schema());
    assert!(
        !sdl.contains("filter: InputAllOptional = {}"),
        "supergraph should drop `= {{}}` when default presence is inconsistent across subgraphs, got:\n{sdl}"
    );
}

/// Partial input object defaults must be preserved as written — composition should not expand
/// them by injecting type-level field defaults for absent fields.
#[test]
fn misc_preserves_partial_input_object_defaults_without_expansion() {
    let subgraph = ServiceDefinition {
        name: "subgraph",
        type_defs: r#"
        type Query {
          products(filter: SearchFilter = {paging: {limit: 10}, sorting: []}): [Product!]!
        }

        type Product @key(fields: "id") {
          id: ID!
          name: String!
        }

        input SearchFilter {
          paging: PagingInput = {limit: 10}
          sorting: [SortInput!] = []
          inStock: Boolean = true
        }

        input PagingInput {
          limit: Int = 10
        }

        input SortInput {
          field: String = "created_at"
          direction: String = "DESC"
        }
        "#,
    };

    let supergraph = compose_as_fed2_subgraphs(&[subgraph]).expect("composition should succeed");
    let query = supergraph
        .schema()
        .schema()
        .get_object("Query")
        .expect("Query type should exist in the supergraph");
    assert_snapshot!(query);
}

/// Defaults inside list elements should also be preserved without expansion.
#[test]
fn misc_preserves_defaults_inside_list_elements() {
    let subgraph = ServiceDefinition {
        name: "subgraph",
        type_defs: r#"
        type Query {
          products(sort: [SortInput!] = [{}]): [Product!]!
        }

        type Product @key(fields: "id") {
          id: ID!
          name: String!
        }

        input SortInput {
          field: String = "created_at"
          direction: String = "DESC"
        }
        "#,
    };

    let supergraph = compose_as_fed2_subgraphs(&[subgraph]).expect("composition should succeed");
    let query = supergraph
        .schema()
        .schema()
        .get_object("Query")
        .expect("Query type should exist in the schema");
    assert_snapshot!(query);
}

#[test]
fn misc_works_with_normal_graphql_type_extension_when_definition_is_empty() {
    let subgraph_a = ServiceDefinition {
        name: "subgraphA",
        type_defs: r#"
        type Query {
          foo: Foo
        }

        type Foo

        extend type Foo {
          bar: String
        }
        "#,
    };

    // NOTE: This test uses composeServices() in JS (Fed1), not composeAsFed2Subgraphs()
    // For now, using Fed2 composition as the equivalent
    let result = compose_as_fed2_subgraphs(&[subgraph_a]);
    let _supergraph =
        result.expect("Expected composition to succeed with empty type definition + extension");
}

#[test]
fn misc_handles_fragments_in_requires_using_inaccessible_types() {
    let subgraph_a = ServiceDefinition {
        name: "subgraphA",
        type_defs: r#"
        type Query @shareable {
          dummy: Entity
        }

        type Entity @key(fields: "id") {
          id: ID!
          data: Foo
        }

        interface Foo {
          foo: String!
        }

        interface Bar implements Foo {
          foo: String!
          bar: String!
        }

        type Baz implements Foo & Bar @shareable {
          foo: String!
          bar: String!
          baz: String!
        }

        type Qux implements Foo & Bar @shareable {
          foo: String!
          bar: String!
          qux: String!
        }
        "#,
    };

    let subgraph_b = ServiceDefinition {
        name: "subgraphB",
        type_defs: r#"
        type Query @shareable {
          dummy: Entity
        }

        type Entity @key(fields: "id") {
          id: ID!
          data: Foo @external
          requirer: String! @requires(fields: "data { foo ... on Bar { bar ... on Baz { baz } ... on Qux { qux } } }")
        }

        interface Foo {
          foo: String!
        }

        interface Bar implements Foo {
          foo: String!
          bar: String!
        }

        type Baz implements Foo & Bar @shareable @inaccessible {
          foo: String!
          bar: String!
          baz: String!
        }

        type Qux implements Foo & Bar @shareable {
          foo: String!
          bar: String!
          qux: String!
        }
        "#,
    };

    let result = compose_as_fed2_subgraphs(&[subgraph_a, subgraph_b]);
    let supergraph = result.expect(
        "Expected composition to succeed with @requires fragments using @inaccessible types",
    );
    let api_schema = supergraph
        .to_api_schema(Default::default())
        .expect("Expected API schema generation to succeed");

    // Validate that @inaccessible type Baz is excluded from API schema but Qux is included
    assert_snapshot!(print_sdl(api_schema.schema()), @r###"
    interface Bar implements Foo {
      foo: String!
      bar: String!
    }

    type Entity {
      id: ID!
      data: Foo
      requirer: String!
    }

    interface Foo {
      foo: String!
    }

    type Query {
      dummy: Entity
    }

    type Qux implements Foo & Bar {
      foo: String!
      bar: String!
      qux: String!
    }
    "###);
}

#[test]
fn misc_existing_authenticated_directive_with_fed1() {
    let subgraph_a = Subgraph::parse(
        "subgraphA",
        "http://subgraphA",
        r#"
        directive @authenticated(scope: [String!]) repeatable on FIELD_DEFINITION

        extend type Foo @key(fields: "id") {
          id: ID!
          name: String! @authenticated(scope: ["read:foo"])
        }
        "#,
    )
    .expect("valid subgraph");

    let subgraph_b = Subgraph::parse(
        "subgraphB",
        "http://subgraphB",
        r#"
        type Query {
          foo: Foo
        }

        type Foo @key(fields: "id") {
          id: ID!
        }
        "#,
    )
    .expect("valid subgraph");

    let result = compose(vec![subgraph_a, subgraph_b])
        .expect("Expected composition to succeed with existing @authenticated directive");

    assert!(
        !result
            .schema()
            .schema()
            .directive_definitions
            .contains_key("@authenticated")
    );
}

#[test]
fn composes_subgraphs_with_overridden_fields_on_renamed_root_types() {
    // Test that @override directives work correctly when root operation types are renamed
    // during normalization (e.g., MyMutation -> Mutation).
    // This is a regression test for a bug where directive referencers were not updated
    // after type renaming, causing @override directives to not be recognized.

    let subgraph_a = ServiceDefinition {
        name: "subgraph-a",
        type_defs: r#"
            schema {
                query: Query
                mutation: MyMutation
            }

            type Query {
                user(id: ID!): User @shareable
            }

            type MyMutation {
                createUser(name: String!): User! @override(from: "subgraph-b")
                updateUser(id: ID!, name: String!): User! @override(from: "subgraph-b")
            }

            type User @key(fields: "id") {
                id: ID!
                name: String!
            }
        "#,
    };

    let subgraph_b = ServiceDefinition {
        name: "subgraph-b",
        type_defs: r#"
            schema {
                query: Query
                mutation: Mutation
            }

            type Query {
                user(id: ID!): User @shareable
            }

            type Mutation @shareable {
                createUser(name: String!): User!
                updateUser(id: ID!, name: String!): User!
            }

            type User @key(fields: "id") {
                id: ID!
                email: String
            }
        "#,
    };

    let result = compose_as_fed2_subgraphs(&[subgraph_a, subgraph_b]);

    // Before the fix, this would fail with INVALID_FIELD_SHARING errors because
    // the @override directives on MyMutation fields were not recognized after
    // MyMutation was renamed to Mutation during normalization.
    let _supergraph = result.expect("Expected composition to succeed");
}

#[test]
fn test_satisfiability_handles_extra_implicit_downcast() {
    // Regression test for satisfiability validation with interface/implementation type covariance.
    // When a @shareable field returns different but compatible types across subgraphs
    // (e.g., A in one, I interface in another), the supergraph uses the interface type.
    // During satisfiability validation, when the supergraph tries to downcast to the
    // implementation type, if a subgraph is already at that type, the downcast should
    // be treated as a no-op rather than failing with "cannot find type".

    let subgraph_a = r#"
        schema @link(url: "https://specs.apollo.dev/federation/v2.3", import: ["@key", "@shareable", "@override"]) {
            query: Query
            mutation: MyMutation
        }

        type Query { dummy: String @shareable }

        type MyMutation {
            doSomething(input: Input!): T! @override(from: "subgraph-b")
        }

        input Input { value: String! }

        type T @shareable {
            field: A!
        }

        interface I {
            id: ID!
        }

        type A implements I @key(fields: "id") @shareable {
            id: ID!
            name: String
        }
    "#;

    let subgraph_b = r#"
        schema @link(url: "https://specs.apollo.dev/federation/v2.3", import: ["@key", "@shareable"]) {
            query: Query
            mutation: Mutation
        }

        type Query { dummy: String @shareable }

        type Mutation @shareable {
            doSomething(input: Input!): T!
        }

        input Input { value: String! }

        type T @shareable {
            field: I!
        }

        interface I {
            id: ID!
        }

        type A implements I @key(fields: "id", resolvable: false) @shareable {
            id: ID!
        }
    "#;

    let parsed_a = Subgraph::parse("subgraph-a", "http://subgraph-a", subgraph_a)
        .expect("Failed to parse subgraph-a");
    let parsed_b = Subgraph::parse("subgraph-b", "http://subgraph-b", subgraph_b)
        .expect("Failed to parse subgraph-b");

    // Before the fix, this would fail with:
    // SATISFIABILITY_ERROR: cannot find type "A" in subgraph "subgraph-a"
    // because the validator tried to downcast from I to A, but subgraph-a was already
    // at A (no downcast edge needed).
    let result = compose(vec![parsed_a, parsed_b]);
    result.expect("Expected composition to succeed");
}

#[test]
fn composes_input_field_with_int_to_float_coercible_defaults() {
    // Regression test for input field default value coercibility.
    // When an input field has type Float, default values of 200 (Int) and 200.0 (Float)
    // should be considered compatible because Int values are coercible to Float.
    // This should not produce an INPUT_FIELD_DEFAULT_MISMATCH error.

    let subgraph_a = ServiceDefinition {
        name: "subgraph-a",
        type_defs: r#"
            type Query {
                foo(input: InputA): [A!]! @shareable
            }

            input InputA {
                value: Float! = 200
                unit: String! = "meters"
            }

            type A @shareable {
                id: ID!
                name: String!
            }
        "#,
    };

    let subgraph_b = ServiceDefinition {
        name: "subgraph-b",
        type_defs: r#"
            type Query {
                foo(input: InputA): [A!]! @shareable
            }

            input InputA {
                value: Float! = 200.0
                unit: String! = "meters"
            }

            type A @shareable {
                id: ID!
                name: String!
            }
        "#,
    };

    let result = compose_as_fed2_subgraphs(&[subgraph_a, subgraph_b]);

    // This should succeed because 200 (Int) is coercible to 200.0 (Float)
    let _supergraph = result
        .expect("Expected composition to succeed with Int default coercible to Float default");
}

#[test]
fn composes_subgraphs_with_directives_on_renamed_root_types() {
    let subgraph_a = ServiceDefinition {
        name: "subgraph-a",
        type_defs: r#"
            schema {
                query: MyQuery
                mutation: MyMutation
            }

            type MyQuery @tag(name: "custom") {
                hello(name: String! @tag(name: "custom")): String @tag(name: "custom")
            }

            type MyMutation @tag(name: "custom") {
                bye(name: String! @tag(name: "custom")): String! @tag(name: "custom")
            }
        "#,
    };

    let subgraph_b = ServiceDefinition {
        name: "subgraph-b",
        type_defs: r#"
            schema {
                query: Query
                mutation: Mutation
            }

            type Query {
                helloWorld: String
            }

            type Mutation {
                goodbyeWorld: String
            }
        "#,
    };

    let result = compose_as_fed2_subgraphs(&[subgraph_a, subgraph_b]);
    let _supergraph = result.expect("Expected composition to succeed");
}

#[test]
fn misc_conflicting_subgraph_names_sanitization() {
    let sg1 = ServiceDefinition {
        name: "mysubgraph",
        type_defs: r#"
        type Query {
          foo: String
        }
        "#,
    };

    let sg2 = ServiceDefinition {
        name: "MySubgraph",
        type_defs: r#"
        type Query {
          bar: String
        }
        "#,
    };

    let result = compose_as_fed2_subgraphs(&[sg1, sg2]);
    let supergraph = result.expect("Expected composition to succeed");

    let schema_str = supergraph.schema().schema().to_string();
    assert!(
        schema_str.contains("MYSUBGRAPH_1"),
        "Expected MYSUBGRAPH_1 in schema"
    );
    assert!(
        schema_str.contains("MYSUBGRAPH_2"),
        "Expected MYSUBGRAPH_2 in schema"
    );
}