@graphql-tools/delegate
Version:
A set of utils for faster development of GraphQL tools
42 lines (41 loc) • 1.92 kB
JavaScript
import { prepareGatewayDocument } from './prepareGatewayDocument.js';
import { finalizeGatewayRequest } from './finalizeGatewayRequest.js';
import { checkResultAndHandleErrors } from './checkResultAndHandleErrors.js';
export class Transformer {
constructor(context) {
this.transformations = [];
this.delegationContext = context;
const transforms = context.transforms;
const delegationTransforms = transforms.slice().reverse();
for (const transform of delegationTransforms) {
this.addTransform(transform, {});
}
}
addTransform(transform, context = {}) {
this.transformations.push({ transform, context });
}
transformRequest(originalRequest) {
var _a;
let request = {
...originalRequest,
document: prepareGatewayDocument(originalRequest.document, this.delegationContext.transformedSchema, this.delegationContext.returnType, (_a = this.delegationContext.info) === null || _a === void 0 ? void 0 : _a.schema),
};
for (const transformation of this.transformations) {
if (transformation.transform.transformRequest) {
request = transformation.transform.transformRequest(request, this.delegationContext, transformation.context);
}
}
return finalizeGatewayRequest(request, this.delegationContext);
}
transformResult(originalResult) {
let result = originalResult;
// from right to left
for (let i = this.transformations.length - 1; i >= 0; i--) {
const transformation = this.transformations[i];
if (transformation.transform.transformResult) {
result = transformation.transform.transformResult(result, this.delegationContext, transformation.context);
}
}
return checkResultAndHandleErrors(result, this.delegationContext);
}
}