@nur840/frame v1.0.4

Layer

Layer trying to cover unprivileged side of any Framework.It's trying to achieve

• 0 Dependencies.
• More Control
• Better Error Handling
• Raw nodejs performance
• Lightweight.
• Make asynchronous programming easy and fast
• And Plugin System

API - Form - Request - Control

• Request(ctx => any) Entry Point.
• Catch((err, ctx) => any) It run when Request() throw any error!
• Control(flow, ctx) => any It run in the end.1st argument is the returned value from Request().
• Context Prototype of ctx object

import http from "http";
import { App, Request, Catch, Control, Context } from "layer";

http.createServer(App).listen(8080); // initialization

Request((ctx) => {
  if (condition) throw new CustomError("Bad Request");
  return "This is so Awesome!";
});

Catch((err, { res }) => {
  if (err instanceof CustomError) res.end(err.msg);
});

Control((flow, ctx) => {
  if (!flow) return; // checking if flow isn't falsy value
  ctx.send(flow);
});

let ctx = Context.prototype;
ctx.prop = "Hello World";
ctx.msg = function () {
  return this.prop;
};
ctx.send = function (prefix) {
  this.res.end(prefix + this.msg());
};

Alias

App.CTX = Context;
App.Catch = Catch;
App.control = Control;
App.request = Request;

Form - Request(use(m1,m2...))

Note: Only use it for Asynchronous Task!

• use() return a function.
• This function take one argument and pass it to All Middleware.
• This function return or throw Error depend on Middleware.

Request(use(middleware1, middleware2, middleware3));

use() can be nested!

// You don't need nesting.Its hard to understand the flow of control.
Request(
  use(
    // if Something Return from Any middleware it will pass to the Control().
    use(Fn1, Fn2),
    use(use(A, B), use(C, D))
  )
);
// Although It could be very useful.Router plugin has `use()` builtin.
// But the `return` value pass to the next middleware.
// where (ctx,flow) => flow; is the returned value from 1st middleware.

let auth = (ctx) => isValid(ctx.id); // return true | false
Route.GET(auth, (ctx, flow) => {
  if (flow == true) return "Layer is so awesome!"; // pass it to the Controller!
});

plugin - Router - Route

init

• initreturn value or throw Error depend on Route

import { init, Route } from "layer/Router";

Request(init); // initialization

Route("/")
  .GET((ctx) => {
    ctx.res.end("Hello World");
  })
  .POST(({ res }) => {
    res.end("I can chaining!");
  });

Router - Route (controlling)

If Route returned or Throw any error.It just a returned Value of init

Route("/").GET((ctx) => {
  (() => {
    if (someCondition) throw "I am more then any middleware!";
  })();
  if (someCondition) return "pass to Control()";
});

Control((flow, ctx) => {
  if (!flow) return;
  // flow = throw value | return value
  ctx.res.end(flow);
});

Manually handel Error on specific route!

Route("/")
  .GET(() => {
    throw new CustomError("Error!");
  })
  .POST(() => {
    throw new Error("Error!");
  })
  .catch((err, ctx) => {
    if (err instanceof CustomError) ctx.res.end(err.msg);
    // throw value of `init`
    if (err instanceof Error) throw "pass err to the Catch()";
    else return err; // return value of `init`
  });

Note: In catch() block, init throw exception if catch block throw any Error!

More Plugin in the Future.