You can pass in additional information that can be used by the middleware.
import { AsyncHooks, type AsyncMiddlewareFn } from "@daiso-tech/core/utilities";
function log<TParameters extends unknown[], TReturn>(): AsyncMiddlewareFn<TParameters, TReturn, { funcName: string; }> {
return async (args, next, { funcName }) => {
console.log("FUNCTION_NAME:", funcName);
console.log("ARGUMENTS:", args);
const value = await next(...args);
console.log("RETURN:", value);
return value;
}
}
function time<TParameters extends unknown[], TReturn>(): AsyncMiddlewareFn<TParameters, TReturn> {
return async (args, next) => {
const start = performance.now();
const value = await next(...args);
const end = performance.now();
const time = end - start;
console.log("TIME:", `${String(time)}ms`);
return value;
}
}
function add(a: number, b: number): number {
return a + b;
}
const enhancedAdd = new AsyncHooks(add, [
log(),
time()
],
// You can provide additional information to `AsyncMiddleware` invokables.
{
funcName: add.name
});
// Will log the function name, arguments and return value.
// Will also log the execution time.
const result = await enhancedAdd.invoke(1, 2);
// Will be 3.
console.log(result);
The invoke method executes the constructor's input function, applying all middlewares.
The pipe method returns a new AsyncHooks instance with the additional middlewares applied.
The pipeWhen method conditionally applies additional middlewares, returning a new AsyncHooks instance only if the specified condition is met.
The toFunc will return the function with all middlewares applied.
The
AsyncHooksclass provides a convenient way to change and inspect arguments and return value of both async and sync functions. For exampleAsyncHooksclass can be used to log function arguments and return values. Note this class will always return promise and is immutable.IMPORT_PATH:
"@daiso-tech/core/utilities"