@envelop/on-resolve
Version:
This plugin allows you to hook into resolves of every field in the GraphQL schema.
58 lines (57 loc) • 2.89 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.useOnResolve = useOnResolve;
const graphql_1 = require("graphql");
const promise_helpers_1 = require("@whatwg-node/promise-helpers");
/**
* Wraps the provided schema by hooking into the resolvers of every field.
*
* Use the `onResolve` argument to manipulate the resolver and its results/errors.
*/
function useOnResolve(onResolve, opts = { skipIntrospection: true }) {
const hasWrappedResolveSymbol = Symbol('hasWrappedResolve');
return {
onSchemaChange({ schema: _schema }) {
const schema = _schema;
if (!schema)
return; // nothing to do if schema is missing
for (const type of Object.values(schema.getTypeMap())) {
if ((!opts.skipIntrospection || !(0, graphql_1.isIntrospectionType)(type)) && (0, graphql_1.isObjectType)(type)) {
for (const field of Object.values(type.getFields())) {
if (field[hasWrappedResolveSymbol])
continue;
let resolver = (field.resolve || graphql_1.defaultFieldResolver);
field.resolve = (root, args, context, info) => (0, promise_helpers_1.handleMaybePromise)(() => onResolve({
root,
args,
context,
info,
resolver,
replaceResolver: newResolver => {
resolver = newResolver;
},
}), afterResolve => {
if (typeof afterResolve === 'function') {
return (0, promise_helpers_1.handleMaybePromise)(() => resolver(root, args, context, info), result => (0, promise_helpers_1.mapMaybePromise)(afterResolve({
result,
setResult: newResult => {
result = newResult;
},
}), () => result), errorResult => (0, promise_helpers_1.handleMaybePromise)(() => afterResolve({
result: errorResult,
setResult: newResult => {
errorResult = newResult;
},
}), () => {
throw errorResult;
}));
}
return resolver(root, args, context, info);
});
field[hasWrappedResolveSymbol] = true;
}
}
}
},
};
}