@graphql-eslint/eslint-plugin/esm/rules/relay-connection-types.js

GraphQL plugin for ESLint

import { Kind } from 'graphql';
const MUST_BE_OBJECT_TYPE = 'MUST_BE_OBJECT_TYPE';
const MUST_CONTAIN_FIELD_EDGES = 'MUST_CONTAIN_FIELD_EDGES';
const MUST_CONTAIN_FIELD_PAGE_INFO = 'MUST_CONTAIN_FIELD_PAGE_INFO';
const MUST_HAVE_CONNECTION_SUFFIX = 'MUST_HAVE_CONNECTION_SUFFIX';
const EDGES_FIELD_MUST_RETURN_LIST_TYPE = 'EDGES_FIELD_MUST_RETURN_LIST_TYPE';
const PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE = 'PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE';
export const NON_OBJECT_TYPES = [
    Kind.SCALAR_TYPE_DEFINITION,
    Kind.UNION_TYPE_DEFINITION,
    Kind.UNION_TYPE_EXTENSION,
    Kind.INPUT_OBJECT_TYPE_DEFINITION,
    Kind.INPUT_OBJECT_TYPE_EXTENSION,
    Kind.ENUM_TYPE_DEFINITION,
    Kind.ENUM_TYPE_EXTENSION,
    Kind.INTERFACE_TYPE_DEFINITION,
    Kind.INTERFACE_TYPE_EXTENSION,
];
const notConnectionTypesSelector = `:matches(${NON_OBJECT_TYPES})[name.value=/Connection$/] > .name`;
const hasEdgesField = (node) => { var _a; return (_a = node.fields) === null || _a === void 0 ? void 0 : _a.some(field => field.name.value === 'edges'); };
const hasPageInfoField = (node) => { var _a; return (_a = node.fields) === null || _a === void 0 ? void 0 : _a.some(field => field.name.value === 'pageInfo'); };
export const rule = {
    meta: {
        type: 'problem',
        docs: {
            category: 'Schema',
            description: [
                'Set of rules to follow Relay specification for Connection types.',
                '',
                '- Any type whose name ends in "Connection" is considered by spec to be a `Connection type`',
                '- Connection type must be an Object type',
                '- Connection type must contain a field `edges` that return a list type that wraps an edge type',
                '- Connection type must contain a field `pageInfo` that return a non-null `PageInfo` Object type',
            ].join('\n'),
            url: 'https://github.com/B2o5T/graphql-eslint/blob/master/docs/rules/relay-connection-types.md',
            isDisabledForAllConfig: true,
            examples: [
                {
                    title: 'Incorrect',
                    code: /* GraphQL */ `
            type UserPayload { # should be an Object type with \`Connection\` suffix
              edges: UserEdge! # should return a list type
              pageInfo: PageInfo # should return a non-null \`PageInfo\` Object type
            }
          `,
                },
                {
                    title: 'Correct',
                    code: /* GraphQL */ `
            type UserConnection {
              edges: [UserEdge]
              pageInfo: PageInfo!
            }
          `,
                },
            ],
        },
        messages: {
            // Connection types
            [MUST_BE_OBJECT_TYPE]: 'Connection type must be an Object type.',
            [MUST_HAVE_CONNECTION_SUFFIX]: 'Connection type must have `Connection` suffix.',
            [MUST_CONTAIN_FIELD_EDGES]: 'Connection type must contain a field `edges` that return a list type.',
            [MUST_CONTAIN_FIELD_PAGE_INFO]: 'Connection type must contain a field `pageInfo` that return a non-null `PageInfo` Object type.',
            [EDGES_FIELD_MUST_RETURN_LIST_TYPE]: '`edges` field must return a list type.',
            [PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE]: '`pageInfo` field must return a non-null `PageInfo` Object type.',
        },
        schema: [],
    },
    create(context) {
        return {
            [notConnectionTypesSelector](node) {
                context.report({ node, messageId: MUST_BE_OBJECT_TYPE });
            },
            ':matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value!=/Connection$/]'(node) {
                if (hasEdgesField(node) && hasPageInfoField(node)) {
                    context.report({ node: node.name, messageId: MUST_HAVE_CONNECTION_SUFFIX });
                }
            },
            ':matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/]'(node) {
                if (!hasEdgesField(node)) {
                    context.report({ node: node.name, messageId: MUST_CONTAIN_FIELD_EDGES });
                }
                if (!hasPageInfoField(node)) {
                    context.report({ node: node.name, messageId: MUST_CONTAIN_FIELD_PAGE_INFO });
                }
            },
            ':matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/] > FieldDefinition[name.value=edges] > .gqlType'(node) {
                const isListType = node.kind === Kind.LIST_TYPE ||
                    (node.kind === Kind.NON_NULL_TYPE && node.gqlType.kind === Kind.LIST_TYPE);
                if (!isListType) {
                    context.report({ node, messageId: EDGES_FIELD_MUST_RETURN_LIST_TYPE });
                }
            },
            ':matches(ObjectTypeDefinition, ObjectTypeExtension)[name.value=/Connection$/] > FieldDefinition[name.value=pageInfo] > .gqlType'(node) {
                const isNonNullPageInfoType = node.kind === Kind.NON_NULL_TYPE &&
                    node.gqlType.kind === Kind.NAMED_TYPE &&
                    node.gqlType.name.value === 'PageInfo';
                if (!isNonNullPageInfoType) {
                    context.report({ node, messageId: PAGE_INFO_FIELD_MUST_RETURN_NON_NULL_TYPE });
                }
            },
        };
    },
};