Express

• Route name couldn’t be /accounts, 404 raised after that.

Node.JS

• Cross require lead target class becomes an empty Object!

  In order to prevent an infinite loop, an unfinished copy of the a.js exports object is returned to the b.js module. b.js then finishes loading, and its exports object is provided to the a.js module. —-https://nodejs.org/api/modules.html

Custom getters

Use custom getters to process the MongoDB retunred data, like an interceptor.

Schema custom getters doesn’t work with lean().

Set up the Schema:

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DBSchema.set('toObject', {getters: true, virtuals: true});
DBSchema.set('toJSON', {getters: true, virtuals: true});

Add custom get function on specified field:

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DBSchema.path('images').get(function (images) {
  if (images && Array.isArray(images) && images.length > 0) {
    images = images.map(function (image) {
      return getUrl(image);
    });
  }
  return images;
});

Read More

Operator delete is unexpectedly slow!

Delete is the only true way to remove object’s properties without any leftovers, but it works ~ 100 times slower, compared to it’s “alternative”, setting object[key] = undefined.

http://stackoverflow.com/a/21735614/1904043

In NodeJS:

require is always “require once”. After you call require the first time, require uses a cache and will always return the same object.

http://stackoverflow.com/questions/8958097/is-there-a-way-to-require-a-js-file-only-once-in-nodejs

ONE script to understand JavaScript OO :-)

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function MyClass () { // constructor function
  var privateVariable = "foo";  // Private variable 

  this.publicVariable = "bar";  // Public variable 

  this.privilegedMethod = function () {  // Public Method
    alert(privateVariable);
  };
}

// Instance method will be available to all instance but only load once in memory 
MyClass.prototype.publicMethod = function () {    
  alert(this.publicVariable);
};

// Static variable shared by all instance 
MyClass.staticProperty = "baz";

//...
var myInstance = new MyClass();

Clipped from StackOverflow: http://stackoverflow.com/a/1535687/1904043