apollo-federation 2.16.0

Apollo Federation
Documentation
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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 {
          required: String!
        }

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

    let supergraph = compose_as_fed2_subgraphs(&[subgraph]).expect("composition should succeed");
    assert_snapshot!(supergraph.schema().schema());
}

#[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"
    );
}

mod supergraph_spec_imports {
    use apollo_federation::subgraph::typestate::Subgraph;
    use insta::assert_snapshot;

    use crate::composition::assert_composition_errors;
    use crate::composition::compose;

    #[test]
    fn fed2_with_explicit_supergraph_spec_import_propagates_policy() {
        let sdl = r#"
            extend schema
                @link(url: "https://specs.apollo.dev/federation/v2.5", import: ["@key"])
                @link(url: "https://specs.apollo.dev/policy/v0.1", for: SECURITY)

            type Query {
                user(id: ID!): Account
            }

            type Account @key(fields: "id") {
                id: ID!
                rate: Float @policy(policies: [["view_rate"]])
            }
        "#;
        let subgraph =
            Subgraph::parse("accounts", "http://accounts/graphql", sdl).expect("valid subgraph");

        let supergraph = compose(vec![subgraph]).expect("composition should succeed");
        assert_snapshot!(supergraph.schema().schema());
    }

    #[test]
    fn fed2_with_overlapping_inaccessible_import_errors() {
        let sdl = r#"
            extend schema
                @link(url: "https://specs.apollo.dev/federation/v2.5", import: ["@key", "@inaccessible"])
                @link(url: "https://specs.apollo.dev/inaccessible/v0.2", for: SECURITY)

            type Query {
                product(id: ID!): Product
            }

            type Product @key(fields: "id") {
                id: ID!
                name: String!
                internalCode: String @inaccessible
            }
        "#;
        let subgraph = Subgraph::parse("products", "http://products/graphql", sdl)
            .expect("successfully parsed");
        let result = compose(vec![subgraph]);
        assert_composition_errors(
            &result,
            &[(
                "INVALID_LINK_DIRECTIVE_USAGE",
                r#"[products] Please import "@inaccessible" from the feature "https://specs.apollo.dev/federation" instead of using "https://specs.apollo.dev/inaccessible" to avoid potential unexpected behavior in the future."#,
            )],
        );
    }

    #[test]
    fn fed2_with_overlapping_policy_and_requires_scopes_imports_errors() {
        let sdl = r#"
            extend schema
                @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key", "@policy", "@requiresScopes"])
                @link(url: "https://specs.apollo.dev/requiresScopes/v0.1", for: SECURITY)
                @link(url: "https://specs.apollo.dev/policy/v0.1", for: SECURITY)

            type Query {
                account(id: ID!): Account
            }

            type Account @key(fields: "id") {
                id: ID!
                balance: Float! @requiresScopes(scopes: [["read:balance"]])
                rate: Float @policy(policies: [["view_rate"]])
            }
        "#;
        let subgraph =
            Subgraph::parse("accounts", "http://accounts/graphql", sdl).expect("valid subgraph");
        let result = compose(vec![subgraph]);
        assert_composition_errors(
            &result,
            &[(
                "INVALID_LINK_DIRECTIVE_USAGE",
                r#"[accounts] Cannot import "@requiresScopes" from feature "https://specs.apollo.dev/federation" since it can be confused with a namespaced name from another linked feature "https://specs.apollo.dev/requiresScopes". Please rename the import or feature to avoid conflicts via "as"."#,
            )],
        );
    }

    #[test]
    fn fed1_with_link_bootstrap_and_supergraph_spec_import_propagates_policy() {
        let sdl = r#"
            schema
                @link(url: "https://specs.apollo.dev/link/v1.0")
                @link(url: "https://specs.apollo.dev/policy/v0.1", for: SECURITY)
            {
                query: Query
            }

            directive @key(fields: String!) repeatable on OBJECT | INTERFACE
            directive @policy(policies: [[policy__Policy!]!]!) on
              | FIELD_DEFINITION
              | OBJECT
              | INTERFACE
              | SCALAR
              | ENUM

            scalar policy__Policy

            type Query {
                account(id: ID!): Account
            }

            type Account @key(fields: "id") {
                id: ID!
                rate: Float @policy(policies: [["view_rate"]])
            }
        "#;
        let subgraph =
            Subgraph::parse("accounts", "http://accounts/graphql", sdl).expect("valid subgraph");

        let supergraph = compose(vec![subgraph]).expect("composition should succeed");
        assert_snapshot!(supergraph.schema().schema());
    }

    #[test]
    fn fed1_with_link_bootstrap_and_inaccessible_spec_import_errors_due_to_collision() {
        let sdl = r#"
            schema
                @link(url: "https://specs.apollo.dev/link/v1.0")
                @link(url: "https://specs.apollo.dev/inaccessible/v0.2")
            {
                query: Query
            }

            type Query {
                product(id: ID!): Product
            }

            type Product {
                id: ID!
                name: String!
                internalCode: String @inaccessible
            }
        "#;
        let subgraph =
            Subgraph::parse("products", "http://products/graphql", sdl).expect("valid subgraph");
        let result = compose(vec![subgraph]);
        assert_composition_errors(
            &result,
            &[(
                "INVALID_LINK_DIRECTIVE_USAGE",
                r#"[products] Please import "@inaccessible" from the feature "https://specs.apollo.dev/federation" instead of using "https://specs.apollo.dev/inaccessible" to avoid potential unexpected behavior in the future."#,
            )],
        );
    }

    #[test]
    fn fed1_without_link_bootstrap_drops_supergraph_spec_import_of_policy() {
        let sdl = r#"
            extend schema
                @link(url: "https://specs.apollo.dev/policy/v0.1", for: SECURITY)

            directive @key(fields: String!) repeatable on OBJECT | INTERFACE
            directive @policy(policies: [[policy__Policy!]!]!) on
              | FIELD_DEFINITION
              | OBJECT
              | INTERFACE
              | SCALAR
              | ENUM

            scalar policy__Policy

            type Query {
                account(id: ID!): Account
            }

            type Account @key(fields: "id") {
                id: ID!
                rate: Float @policy(policies: [["view_rate"]])
            }
        "#;
        let subgraph =
            Subgraph::parse("accounts", "http://accounts/graphql", sdl).expect("valid subgraph");

        let supergraph = compose(vec![subgraph]).expect("composition should succeed");
        let schema = supergraph.schema().schema();

        assert!(
            !schema.directive_definitions.contains_key("policy"),
            "Supergraph should NOT contain @policy when @link is not bootstrapped"
        );
    }
}