| /** @category Validation Rules */ |
| import { GraphQLError } from '../../error/GraphQLError.mjs'; |
| |
| /** |
| * Unique operation types |
| * |
| * A GraphQL document is only valid if it has only one type per operation. |
| * @param context - The validation context used while checking the document. |
| * @returns A visitor that reports validation errors for this rule. |
| * @example |
| * ```ts |
| * import { buildSchema } from 'graphql'; |
| * import { UniqueOperationTypesRule } from 'graphql/validation'; |
| * |
| * const invalidSDL = ` |
| * schema { query: Query query: Other } type Query { name: String } type Other { name: String } |
| * `; |
| * |
| * UniqueOperationTypesRule.name; // => 'UniqueOperationTypesRule' |
| * buildSchema(invalidSDL); // throws an error |
| * |
| * const validSDL = ` |
| * schema { query: Query } type Query { name: String } |
| * `; |
| * |
| * buildSchema(validSDL); // does not throw |
| * ``` |
| */ |
| export function UniqueOperationTypesRule(context) { |
| const schema = context.getSchema(); |
| const definedOperationTypes = Object.create(null); |
| const existingOperationTypes = schema |
| ? { |
| query: schema.getQueryType(), |
| mutation: schema.getMutationType(), |
| subscription: schema.getSubscriptionType(), |
| } |
| : {}; |
| return { |
| SchemaDefinition: checkOperationTypes, |
| SchemaExtension: checkOperationTypes, |
| }; |
| |
| function checkOperationTypes(node) { |
| var _node$operationTypes; |
| |
| // See: https://github.com/graphql/graphql-js/issues/2203 |
| |
| /* c8 ignore next */ |
| const operationTypesNodes = |
| (_node$operationTypes = node.operationTypes) !== null && |
| _node$operationTypes !== void 0 |
| ? _node$operationTypes |
| : []; |
| |
| for (const operationType of operationTypesNodes) { |
| const operation = operationType.operation; |
| const alreadyDefinedOperationType = definedOperationTypes[operation]; |
| |
| if (existingOperationTypes[operation]) { |
| context.reportError( |
| new GraphQLError( |
| `Type for ${operation} already defined in the schema. It cannot be redefined.`, |
| { |
| nodes: operationType, |
| }, |
| ), |
| ); |
| } else if (alreadyDefinedOperationType) { |
| context.reportError( |
| new GraphQLError( |
| `There can be only one ${operation} type in schema.`, |
| { |
| nodes: [alreadyDefinedOperationType, operationType], |
| }, |
| ), |
| ); |
| } else { |
| definedOperationTypes[operation] = operationType; |
| } |
| } |
| |
| return false; |
| } |
| } |