块节点js路由

Question

I am writing node js app and I want to block some urls on my app (turn off for all users). Is it possible to do so? Note: I want to switch off/on registration and authentication. Update: I use express js framework

Answer 1

You can create a middleware that you can use for the routes that you want to block:

var block = false;
var BlockingMiddleware = function(req, res, next) {
  if (block === true)
    return res.send(503); // 'Service Unavailable'
  next();
};

app.get('/registration', BlockingMiddleware, function(req, res) {
  // code here is only executed when block is 'false'
  ...
});

This is a just a simple example, obviously.

EDIT: more elaborate example:

// this could reside in a separate file
var Blocker = function() {
  this.blocked  = false;
};

Blocker.prototype.enableBlock = function() {
  this.blocked = true;
};

Blocker.prototype.disableBlock = function() {
  this.blocked = false;
};

Blocker.prototype.isBlocked = function() {
  return this.blocked === true;
};

Blocker.prototype.middleware = function() {
  var self = this;
  return function(req, res, next) {
    if (self.isBlocked())
      return res.send(503);
    next();
  }
};

var blocker             = new Blocker();
var BlockingMiddleware  = blocker.middleware();

app.get('/registration', BlockingMiddleware, function(req, res) {
  ...
});

// to turn on blocking:
blocker.enableBlock();

// to turn off blocking:
blocker.disableBlock();

(this still introduces global variables, but if you can merge the code that determines your 'blocking' condition into the Blocker class you can probably get rid of them)