@graphql-tools/delegate
Version:
A set of utils for faster development of GraphQL tools
154 lines (153 loc) • 6.89 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.createDefaultExecutor = exports.delegateRequest = exports.delegateToSchema = void 0;
const graphql_1 = require("graphql");
const batch_execute_1 = require("@graphql-tools/batch-execute");
const executor_1 = require("@graphql-tools/executor");
const utils_1 = require("@graphql-tools/utils");
const applySchemaTransforms_js_1 = require("./applySchemaTransforms.js");
const createRequest_js_1 = require("./createRequest.js");
const Subschema_js_1 = require("./Subschema.js");
const subschemaConfig_js_1 = require("./subschemaConfig.js");
const Transformer_js_1 = require("./Transformer.js");
function delegateToSchema(options) {
const { info, schema, rootValue = schema.rootValue ?? info.rootValue, operationName = info.operation.name?.value, operation = (0, createRequest_js_1.getDelegatingOperation)(info.parentType, info.schema), fieldName = info.fieldName, selectionSet, fieldNodes = info.fieldNodes, context, } = options;
const request = (0, createRequest_js_1.createRequest)({
sourceSchema: info.schema,
sourceParentType: info.parentType,
sourceFieldName: info.fieldName,
fragments: info.fragments,
variableDefinitions: info.operation.variableDefinitions,
variableValues: info.variableValues,
targetRootValue: rootValue,
targetOperationName: operationName,
targetOperation: operation,
targetFieldName: fieldName,
selectionSet,
fieldNodes,
context,
info,
});
return delegateRequest({
...options,
request,
});
}
exports.delegateToSchema = delegateToSchema;
function getDelegationReturnType(targetSchema, operation, fieldName) {
const rootType = (0, utils_1.getDefinedRootType)(targetSchema, operation);
const rootFieldType = rootType.getFields()[fieldName];
if (!rootFieldType) {
throw new Error(`Unable to find field '${fieldName}' in type '${rootType}'.`);
}
return rootFieldType.type;
}
function delegateRequest(options) {
const delegationContext = getDelegationContext(options);
const transformer = new Transformer_js_1.Transformer(delegationContext);
const processedRequest = transformer.transformRequest(options.request);
if (options.validateRequest) {
validateRequest(delegationContext, processedRequest.document);
}
const executor = getExecutor(delegationContext);
const result$ = executor(processedRequest);
function handleExecutorResult(executorResult) {
if ((0, utils_1.isAsyncIterable)(executorResult)) {
const iterator = executorResult[Symbol.asyncIterator]();
// "subscribe" to the subscription result and map the result through the transforms
return (0, utils_1.mapAsyncIterator)(iterator, result => transformer.transformResult(result));
}
return transformer.transformResult(executorResult);
}
if ((0, utils_1.isPromise)(result$)) {
return result$.then(handleExecutorResult);
}
return handleExecutorResult(result$);
}
exports.delegateRequest = delegateRequest;
function getDelegationContext({ request, schema, fieldName, returnType, args, info, transforms = [], transformedSchema, skipTypeMerging = false, }) {
const operationDefinition = (0, utils_1.getOperationASTFromRequest)(request);
let targetFieldName;
if (fieldName == null) {
targetFieldName = operationDefinition.selectionSet.selections[0].name.value;
}
else {
targetFieldName = fieldName;
}
const stitchingInfo = info?.schema.extensions?.['stitchingInfo'];
const subschemaOrSubschemaConfig = stitchingInfo?.subschemaMap.get(schema) ?? schema;
const operation = operationDefinition.operation;
if ((0, subschemaConfig_js_1.isSubschemaConfig)(subschemaOrSubschemaConfig)) {
const targetSchema = subschemaOrSubschemaConfig.schema;
return {
subschema: schema,
subschemaConfig: subschemaOrSubschemaConfig,
targetSchema,
operation,
fieldName: targetFieldName,
args,
context: request.context,
info,
returnType: returnType ??
info?.returnType ??
getDelegationReturnType(targetSchema, operation, targetFieldName),
transforms: subschemaOrSubschemaConfig.transforms != null
? subschemaOrSubschemaConfig.transforms.concat(transforms)
: transforms,
transformedSchema: transformedSchema ??
(subschemaOrSubschemaConfig instanceof Subschema_js_1.Subschema
? subschemaOrSubschemaConfig.transformedSchema
: (0, applySchemaTransforms_js_1.applySchemaTransforms)(targetSchema, subschemaOrSubschemaConfig)),
skipTypeMerging,
};
}
return {
subschema: schema,
subschemaConfig: undefined,
targetSchema: subschemaOrSubschemaConfig,
operation,
fieldName: targetFieldName,
args,
context: request.context,
info,
returnType: returnType ??
info?.returnType ??
getDelegationReturnType(subschemaOrSubschemaConfig, operation, targetFieldName),
transforms,
transformedSchema: transformedSchema ?? subschemaOrSubschemaConfig,
skipTypeMerging,
};
}
function validateRequest(delegationContext, document) {
const errors = (0, graphql_1.validate)(delegationContext.targetSchema, document);
if (errors.length > 0) {
if (errors.length > 1) {
const combinedError = new AggregateError(errors, errors.map(error => error.message).join(', \n'));
throw combinedError;
}
const error = errors[0];
throw error.originalError || error;
}
}
const GLOBAL_CONTEXT = {};
function getExecutor(delegationContext) {
const { subschemaConfig, targetSchema, context } = delegationContext;
let executor = subschemaConfig?.executor || (0, exports.createDefaultExecutor)(targetSchema);
if (subschemaConfig?.batch) {
const batchingOptions = subschemaConfig?.batchingOptions;
executor = (0, batch_execute_1.getBatchingExecutor)(context ?? GLOBAL_CONTEXT, executor, batchingOptions?.dataLoaderOptions, batchingOptions?.extensionsReducer);
}
return executor;
}
exports.createDefaultExecutor = (0, utils_1.memoize1)(function createDefaultExecutor(schema) {
return function defaultExecutor(request) {
return (0, executor_1.normalizedExecutor)({
schema,
document: request.document,
rootValue: request.rootValue,
contextValue: request.context,
variableValues: request.variables,
operationName: request.operationName,
});
};
});