Documentation / @agentick/kernel / Middleware

Type Alias: Middleware()<TArgs>

Middleware<TArgs> = (args, envelope, next) => Promise<any>

Defined in: kernel/src/procedure.ts:174

Middleware function that can intercept and transform procedure execution.

Middleware can:

• Transform input arguments before passing to the next middleware/handler
• Modify the result after next() returns
• Short-circuit execution by not calling next()
• Handle or transform errors

Type Parameters

TArgs

TArgs extends any[] = any[]

The argument types of the procedure

Parameters

args

TArgs

envelope

ProcedureEnvelope<TArgs>

next

(transformedArgs?) => Promise<any>

Returns

Promise<any>

Examples

const loggingMiddleware: Middleware<[string]> = async (args, envelope, next) => {
  console.log(`${envelope.operationName} called with:`, args);
  const start = Date.now();
  try {
    const result = await next();
    console.log(`Completed in ${Date.now() - start}ms`);
    return result;
  } catch (error) {
    console.error(`Failed:`, error);
    throw error;
  }
};

const upperMiddleware: Middleware<[string]> = async (args, envelope, next) => {
  return next([args[0].toUpperCase()]);
};

See

• ProcedureEnvelope - The envelope containing execution metadata
• createPipeline - Bundle multiple middleware for reuse