@graphql-tools/delegate
Version:
A set of utils for faster development of GraphQL tools
150 lines (149 loc) • 6.98 kB
JavaScript
import { GraphQLError, isAbstractType, locatedError, responsePathAsArray, } from 'graphql';
import { collectFields, isPromise, memoize1, mergeDeep, relocatedError, } from '@graphql-tools/utils';
import { leftOverByDelegationPlan, PLAN_LEFT_OVER } from './leftOver.js';
import { FIELD_SUBSCHEMA_MAP_SYMBOL, OBJECT_SUBSCHEMA_SYMBOL, UNPATHED_ERRORS_SYMBOL, } from './symbols.js';
export function isExternalObject(data) {
return data[UNPATHED_ERRORS_SYMBOL] !== undefined;
}
export function annotateExternalObject(object, errors, subschema, subschemaMap) {
Object.defineProperties(object, {
[OBJECT_SUBSCHEMA_SYMBOL]: { value: subschema },
[FIELD_SUBSCHEMA_MAP_SYMBOL]: { value: subschemaMap },
[UNPATHED_ERRORS_SYMBOL]: { value: errors },
});
return object;
}
export function getSubschema(object, responseKey) {
return object[FIELD_SUBSCHEMA_MAP_SYMBOL]?.[responseKey] ?? object[OBJECT_SUBSCHEMA_SYMBOL];
}
export function getUnpathedErrors(object) {
return object[UNPATHED_ERRORS_SYMBOL];
}
const EMPTY_ARRAY = [];
const EMPTY_OBJECT = Object.create(null);
export const getActualFieldNodes = memoize1(function (fieldNode) {
return [fieldNode];
});
export function mergeFields(mergedTypeInfo, object, sourceSubschema, context, info) {
const delegationMaps = mergedTypeInfo.delegationPlanBuilder(info.schema, sourceSubschema, info.variableValues != null && Object.keys(info.variableValues).length > 0
? info.variableValues
: EMPTY_OBJECT, info.fragments != null && Object.keys(info.fragments).length > 0
? info.fragments
: EMPTY_OBJECT, info.fieldNodes?.length
? info.fieldNodes.length === 1
? getActualFieldNodes(info.fieldNodes[0])
: info.fieldNodes
: EMPTY_ARRAY);
const leftOver = leftOverByDelegationPlan.get(delegationMaps);
if (leftOver) {
object[PLAN_LEFT_OVER] = leftOver;
}
const res$ = delegationMaps.reduce((prev, delegationMap) => {
function executeFn() {
return executeDelegationStage(mergedTypeInfo, delegationMap, object, context, info);
}
if (isPromise(prev)) {
return prev.then(executeFn);
}
return executeFn();
}, undefined);
function handleDelegationPlanResult() {
return object;
}
if (isPromise(res$)) {
return res$.then(handleDelegationPlanResult);
}
return handleDelegationPlanResult();
}
export function handleResolverResult(resolverResult, subschema, selectionSet, object, combinedFieldSubschemaMap, info, path, combinedErrors) {
if (resolverResult instanceof Error || resolverResult == null) {
const schema = subschema.transformedSchema || info.schema;
const type = schema.getType(object.__typename);
const { fields } = collectFields(schema, EMPTY_OBJECT, EMPTY_OBJECT, type, selectionSet);
const nullResult = {};
for (const [responseKey, fieldNodes] of fields) {
const combinedPath = [...path, responseKey];
if (resolverResult instanceof GraphQLError) {
nullResult[responseKey] = relocatedError(resolverResult, combinedPath);
}
else if (resolverResult instanceof Error) {
nullResult[responseKey] = locatedError(resolverResult, fieldNodes, combinedPath);
}
else {
nullResult[responseKey] = null;
}
}
resolverResult = nullResult;
}
else {
if (resolverResult[UNPATHED_ERRORS_SYMBOL]) {
combinedErrors.push(...resolverResult[UNPATHED_ERRORS_SYMBOL]);
}
}
const objectSubschema = resolverResult[OBJECT_SUBSCHEMA_SYMBOL];
const fieldSubschemaMap = resolverResult[FIELD_SUBSCHEMA_MAP_SYMBOL];
for (const responseKey in resolverResult) {
if (responseKey === '__proto__') {
continue;
}
const existingPropValue = object[responseKey];
const sourcePropValue = resolverResult[responseKey];
if (responseKey === '__typename' &&
existingPropValue !== sourcePropValue &&
isAbstractType(subschema.transformedSchema.getType(sourcePropValue))) {
continue;
}
if (sourcePropValue != null || existingPropValue == null) {
if (existingPropValue != null &&
typeof existingPropValue === 'object' &&
Object.keys(existingPropValue).length > 0) {
if (Array.isArray(existingPropValue) &&
Array.isArray(sourcePropValue) &&
existingPropValue.length === sourcePropValue.length) {
object[responseKey] = existingPropValue.map((existingElement, index) => sourcePropValue instanceof Error
? existingElement
: mergeDeep([existingElement, sourcePropValue[index]]));
}
else if (!(sourcePropValue instanceof Error)) {
object[responseKey] = mergeDeep([existingPropValue, sourcePropValue]);
}
}
else {
object[responseKey] = sourcePropValue;
}
}
combinedFieldSubschemaMap[responseKey] =
fieldSubschemaMap?.[responseKey] ?? objectSubschema ?? subschema;
}
}
function executeDelegationStage(mergedTypeInfo, delegationMap, object, context, info) {
const combinedErrors = object[UNPATHED_ERRORS_SYMBOL];
const path = responsePathAsArray(info.path);
const combinedFieldSubschemaMap = object[FIELD_SUBSCHEMA_MAP_SYMBOL];
const jobs = [];
for (const [subschema, selectionSet] of delegationMap) {
const schema = subschema.transformedSchema || info.schema;
const type = schema.getType(object.__typename);
const resolver = mergedTypeInfo.resolvers.get(subschema);
if (resolver) {
try {
const resolverResult$ = resolver(object, context, info, subschema, selectionSet, undefined, type);
if (isPromise(resolverResult$)) {
jobs.push(resolverResult$.then(resolverResult => handleResolverResult(resolverResult, subschema, selectionSet, object, combinedFieldSubschemaMap, info, path, combinedErrors)).catch(error => handleResolverResult(error, subschema, selectionSet, object, combinedFieldSubschemaMap, info, path, combinedErrors)));
}
else {
handleResolverResult(resolverResult$, subschema, selectionSet, object, combinedFieldSubschemaMap, info, path, combinedErrors);
}
}
catch (error) {
handleResolverResult(error, subschema, selectionSet, object, combinedFieldSubschemaMap, info, path, combinedErrors);
}
}
}
if (jobs.length) {
if (jobs.length === 1) {
return jobs[0];
}
return Promise.all(jobs);
}
}