Demand control directive validations (#3148)

Adds validations to subgraph directive applications, per the
specification in
https://ibm.github.io/graphql-specs/cost-spec.html#sec-Validation. These
rules primarily assert that the @cost and @listsize directive arguments
reference valid fields of the correct type for each application.

<!-- ROUTER-741 -->

.changeset/tidy-trees-dress.md

@@ -0,0 +1,5 @@
+---
+"@apollo/federation-internals": patch
+---
+
+Add validations for demand control directive applications

docs/source/federation-versions.mdx

@@ -44,7 +44,7 @@ First release
 
 Minimum router version
 
-**TBD**
+**1.53.0**
 
 </div>
 

internals-js/src/__tests__/subgraphValidation.test.ts

@@ -1484,3 +1484,188 @@ describe('@interfaceObject/@key on interfaces validation', () => {
  ]);
  });
 });
+
+describe('@cost', () => {
+ it('rejects applications on interfaces', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@cost"])
+
+ type Query {
+ a: A
+ }
+
+ interface A {
+ x: Int @cost(weight: 10)
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'COST_APPLIED_TO_INTERFACE_FIELD',
+ `[S] @cost cannot be applied to interface "A.x"`,
+ ],
+ ]);
+ });
+});
+
+describe('@listSize', () => {
+ it('rejects applications on non-lists (unless it uses sizedFields)', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ a1: A @listSize(assumedSize: 5)
+ a2: A @listSize(assumedSize: 10, sizedFields: ["ints"])
+ }
+
+ type A {
+ ints: [Int]
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ ['LIST_SIZE_APPLIED_TO_NON_LIST', `[S] "Query.a1" is not a list`],
+ ]);
+ });
+
+ it('rejects negative assumedSize', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ a: [Int] @listSize(assumedSize: -5)
+ b: [Int] @listSize(assumedSize: 0)
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_INVALID_ASSUMED_SIZE',
+ `[S] Assumed size of "Query.a" cannot be negative`,
+ ],
+ ]);
+ });
+
+ it('rejects slicingArguments which are not arguments of the field', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ myField(something: Int): [String]
+ @listSize(slicingArguments: ["missing1", "missing2"])
+ myOtherField(somethingElse: String): [Int]
+ @listSize(slicingArguments: ["alsoMissing"])
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_INVALID_SLICING_ARGUMENT',
+ `[S] Slicing argument "missing1" is not an argument of "Query.myField"`,
+ ],
+ [
+ 'LIST_SIZE_INVALID_SLICING_ARGUMENT',
+ `[S] Slicing argument "missing2" is not an argument of "Query.myField"`,
+ ],
+ [
+ 'LIST_SIZE_INVALID_SLICING_ARGUMENT',
+ `[S] Slicing argument "alsoMissing" is not an argument of "Query.myOtherField"`,
+ ],
+ ]);
+ });
+
+ it('rejects slicingArguments which are not Int or Int!', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ sliced(first: String, second: Int, third: Int!): [String]
+ @listSize(slicingArguments: ["first", "second", "third"])
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_INVALID_SLICING_ARGUMENT',
+ `[S] Slicing argument "Query.sliced(first:)" must be Int or Int!`,
+ ],
+ ]);
+ });
+
+ it('rejects sizedFields when the output type is not an object', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ notObject: Int @listSize(assumedSize: 1, sizedFields: ["anything"])
+ a: A @listSize(assumedSize: 5, sizedFields: ["ints"])
+ b: B @listSize(assumedSize: 10, sizedFields: ["ints"])
+ }
+
+ type A {
+ ints: [Int]
+ }
+
+ interface B {
+ ints: [Int]
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_INVALID_SIZED_FIELD',
+ `[S] Sized fields cannot be used because "Int" is not an object type`,
+ ],
+ ]);
+ });
+
+ it('rejects sizedFields which are not fields of the output type', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ a: A @listSize(assumedSize: 5, sizedFields: ["notOnA"])
+ }
+
+ type A {
+ ints: [Int]
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_INVALID_SIZED_FIELD',
+ `[S] Sized field "notOnA" is not a field on type "A"`,
+ ],
+ ]);
+ });
+
+ it('rejects sizedFields which are not lists', () => {
+ const doc = gql`
+ extend schema
+ @link(url: "https://specs.apollo.dev/cost/v0.1", import: ["@listSize"])
+
+ type Query {
+ a: A @listSize(assumedSize: 5, sizedFields: ["notList"])
+ }
+
+ type A {
+ notList: String
+ }
+ `;
+
+ expect(buildForErrors(doc)).toStrictEqual([
+ [
+ 'LIST_SIZE_APPLIED_TO_NON_LIST',
+ `[S] Sized field "A.notList" is not a list`,
+ ],
+ ]);
+ });
+});

internals-js/src/error.ts

@@ -710,6 +710,36 @@ const CONTEXTUAL_ARGUMENT_NOT_CONTEXTUAL_IN_ALL_SUBGRAPHS = makeCodeDefinition(
  { addedIn: '2.7.0' },
 );
 
+const COST_APPLIED_TO_INTERFACE_FIELD = makeCodeDefinition(
+ 'COST_APPLIED_TO_INTERFACE_FIELD',
+ 'The `@cost` directive must be applied to concrete types',
+ { addedIn: '2.9.2' },
+);
+
+const LIST_SIZE_APPLIED_TO_NON_LIST = makeCodeDefinition(
+ 'LIST_SIZE_APPLIED_TO_NON_LIST',
+ 'The `@listSize` directive must be applied to list types',
+ { addedIn: '2.9.2' },
+);
+
+const LIST_SIZE_INVALID_ASSUMED_SIZE = makeCodeDefinition(
+ 'LIST_SIZE_INVALID_ASSUMED_SIZE',
+ 'The `@listSize` directive assumed size cannot be negative',
+ { addedIn: '2.9.2' },
+);
+
+const LIST_SIZE_INVALID_SLICING_ARGUMENT = makeCodeDefinition(
+ 'LIST_SIZE_INVALID_SLICING_ARGUMENT',
+ 'The `@listSize` directive must have existing integer slicing arguments',
+ { addedIn: '2.9.2' },
+);
+
+const LIST_SIZE_INVALID_SIZED_FIELD = makeCodeDefinition(
+ 'LIST_SIZE_INVALID_SIZED_FIELD',
+ 'The `@listSize` directive must reference existing list fields as sized fields',
+ { addedIn: '2.9.2' },
+);
+
 export const ERROR_CATEGORIES = {
  DIRECTIVE_FIELDS_MISSING_EXTERNAL,
  DIRECTIVE_UNSUPPORTED_ON_INTERFACE,
@@ -824,6 +854,12 @@ export const ERRORS = {
  SOURCE_FIELD_SELECTION_INVALID,
  SOURCE_FIELD_NOT_ON_ROOT_OR_ENTITY_FIELD,
  CONTEXTUAL_ARGUMENT_NOT_CONTEXTUAL_IN_ALL_SUBGRAPHS,
+ // Errors related to demand control
+ COST_APPLIED_TO_INTERFACE_FIELD,
+ LIST_SIZE_APPLIED_TO_NON_LIST,
+ LIST_SIZE_INVALID_ASSUMED_SIZE,
+ LIST_SIZE_INVALID_SIZED_FIELD,
+ LIST_SIZE_INVALID_SLICING_ARGUMENT,
 };
 
 const codeDefByCode = Object.values(ERRORS).reduce((obj: {[code: string]: ErrorCodeDefinition}, codeDef: ErrorCodeDefinition) => { obj[codeDef.code] = codeDef; return obj; }, {});