Function: createAppSyncMiddleware()

createAppSyncMiddleware<TSource, TContext, TArgs>(fn): IMiddlewareFunction<TSource, TContext, TArgs>

Defined in: appSyncMiddleware.ts:68

Creates a properly-typed AppSync middleware function.

When using @ttoss/appsync-api, the info object passed to resolvers has the AppSync-specific shape (AppSyncInfo), not the standard GraphQLResolveInfo expected by graphql-middleware. This helper lets you write middlewares with the correct AppSync info type while remaining compatible with the BuildSchemaInput.middlewares array.

Type Parameters

Type Parameter	Default type
TSource	unknown
TContext	unknown
TArgs	unknown

Parameters

Parameter	Type
fn	AppSyncMiddlewareFn<TSource, TContext, TArgs>

Returns

IMiddlewareFunction<TSource, TContext, TArgs>

Example

import { createAppSyncMiddleware } from '@ttoss/appsync-api';

const timingMiddleware = createAppSyncMiddleware(
  async (resolve, source, args, context, info) => {
    const start = Date.now();
    const resolverName = `${info.parentTypeName}.${info.fieldName}`;
    try {
      const result = await resolve(source, args, context, info);
      console.log(`${resolverName} took ${Date.now() - start}ms`);
      return result;
    } catch (error) {
      console.error(`${resolverName} failed after ${Date.now() - start}ms`);
      throw error;
    }
  }
);