UNPKG

@graphql-tools/utils

Version:

Common package containing utils and types for GraphQL tools

160 lines (159 loc) 6.39 kB
import { getDirectiveValues, GraphQLIncludeDirective, GraphQLSkipDirective, isAbstractType, Kind, typeFromAST, } from 'graphql'; import { AccumulatorMap } from './AccumulatorMap.js'; import { GraphQLDeferDirective } from './directives.js'; import { memoize5 } from './memoize.js'; function collectFieldsImpl(schema, fragments, variableValues, runtimeType, selectionSet, fields, patches, visitedFragmentNames) { for (const selection of selectionSet.selections) { switch (selection.kind) { case Kind.FIELD: { if (!shouldIncludeNode(variableValues, selection)) { continue; } fields.add(getFieldEntryKey(selection), selection); break; } case Kind.INLINE_FRAGMENT: { if (!shouldIncludeNode(variableValues, selection) || !doesFragmentConditionMatch(schema, selection, runtimeType)) { continue; } const defer = getDeferValues(variableValues, selection); if (defer) { const patchFields = new AccumulatorMap(); collectFieldsImpl(schema, fragments, variableValues, runtimeType, selection.selectionSet, patchFields, patches, visitedFragmentNames); patches.push({ label: defer.label, fields: patchFields, }); } else { collectFieldsImpl(schema, fragments, variableValues, runtimeType, selection.selectionSet, fields, patches, visitedFragmentNames); } break; } case Kind.FRAGMENT_SPREAD: { const fragName = selection.name.value; if (!shouldIncludeNode(variableValues, selection)) { continue; } const defer = getDeferValues(variableValues, selection); if (visitedFragmentNames.has(fragName) && !defer) { continue; } const fragment = fragments[fragName]; if (!fragment || !doesFragmentConditionMatch(schema, fragment, runtimeType)) { continue; } if (!defer) { visitedFragmentNames.add(fragName); } if (defer) { const patchFields = new AccumulatorMap(); collectFieldsImpl(schema, fragments, variableValues, runtimeType, fragment.selectionSet, patchFields, patches, visitedFragmentNames); patches.push({ label: defer.label, fields: patchFields, }); } else { collectFieldsImpl(schema, fragments, variableValues, runtimeType, fragment.selectionSet, fields, patches, visitedFragmentNames); } break; } } } } /** * Given a selectionSet, collects all of the fields and returns them. * * CollectFields requires the "runtime type" of an object. For a field that * returns an Interface or Union type, the "runtime type" will be the actual * object type returned by that field. * */ export function collectFields(schema, fragments, variableValues, runtimeType, selectionSet) { const fields = new AccumulatorMap(); const patches = []; collectFieldsImpl(schema, fragments, variableValues, runtimeType, selectionSet, fields, patches, new Set()); return { fields, patches }; } /** * Determines if a field should be included based on the `@include` and `@skip` * directives, where `@skip` has higher precedence than `@include`. */ export function shouldIncludeNode(variableValues, node) { const skip = getDirectiveValues(GraphQLSkipDirective, node, variableValues); if (skip?.['if'] === true) { return false; } const include = getDirectiveValues(GraphQLIncludeDirective, node, variableValues); if (include?.['if'] === false) { return false; } return true; } /** * Determines if a fragment is applicable to the given type. */ export function doesFragmentConditionMatch(schema, fragment, type) { const typeConditionNode = fragment.typeCondition; if (!typeConditionNode) { return true; } const conditionalType = typeFromAST(schema, typeConditionNode); if (conditionalType === type) { return true; } if (isAbstractType(conditionalType)) { const possibleTypes = schema.getPossibleTypes(conditionalType); return possibleTypes.includes(type); } return false; } /** * Implements the logic to compute the key of a given field's entry */ export function getFieldEntryKey(node) { return node.alias ? node.alias.value : node.name.value; } /** * Returns an object containing the `@defer` arguments if a field should be * deferred based on the experimental flag, defer directive present and * not disabled by the "if" argument. */ export function getDeferValues(variableValues, node) { const defer = getDirectiveValues(GraphQLDeferDirective, node, variableValues); if (!defer) { return; } if (defer['if'] === false) { return; } return { label: typeof defer['label'] === 'string' ? defer['label'] : undefined, }; } /** * Given an array of field nodes, collects all of the subfields of the passed * in fields, and returns them at the end. * * CollectSubFields requires the "return type" of an object. For a field that * returns an Interface or Union type, the "return type" will be the actual * object type returned by that field. * */ export const collectSubFields = memoize5(function collectSubfields(schema, fragments, variableValues, returnType, fieldNodes) { const subFieldNodes = new AccumulatorMap(); const visitedFragmentNames = new Set(); const subPatches = []; const subFieldsAndPatches = { fields: subFieldNodes, patches: subPatches, }; for (const node of fieldNodes) { if (node.selectionSet) { collectFieldsImpl(schema, fragments, variableValues, returnType, node.selectionSet, subFieldNodes, subPatches, visitedFragmentNames); } } return subFieldsAndPatches; });