isojs

This Meteor package makes sharing code between client, server and mobile better by parsing and removing extraneous code for the server, client or mobile. This means code wrapped with if (Meteor.isServer) {...} won't be served to the client or vice versa. The advantages of this is:

• Smaller payload for the client, mobile and server
• Better sercurity since wrapped server code won't be exposed to the client
• Slightly better performance due to reduction in extraneous code

Methods and functions can now be written for server, client and mobile without worrying too much about payload, security and performance. A good place to use this would be in Meteor methods for stubbing.

Example

The package transforms the following code

Meteor.methods({
  sendMessage: function (msg) {
    if (Meteor.isClient) {
      UpdateView();

      if (Meteor.isCordova) {
        SendPush();
      }
    }

    if (Meteor.isServer) {
      Messages.insert({msg: msg});
    }
  }
});

to this:

Server

Meteor.methods({
  sendMessage: function (msg) {
    Messages.insert({msg: msg});
  }
});

Client - Browser

Meteor.methods({
  sendMessage: function (msg) {
    UpdateView();
  }
});

Client - Mobile

Meteor.methods({
  sendMessage: function (msg) {
    UpdateView();
    SendPush();
  }
});

Usage

Warning!

This package is a proof of concept and is not recommended for use in production.

Install

meteor add xamfoo:isojs

Filenames

Save your code with file extension .isojs

Configure your IDE to recognize .isojs as javascript

Wrapping

Wrap your code in the any of the following formats.

If blocks

if (Meteor.isXX) {...}

Code wrapped in if (Meteor.isServer) {...} is removed in the client payload and flattened in the server payload.

Code wrapped in if (Meteor.isClient) {...} is removed in the server payload and flattened in the client payload.

Code wrapped in if (Meteor.isCordova) {...} is removed in the server and browser payload, and flattened in the cordova payload.

Flattening means the following:

if (Meteor.isServer) {doSomething();}

transforms to this in the server payload:

doSomething();

NOT(!) operator

if (!Meteor.isXX) {...}

A single ! operator is supported to turn a truthy block to a falsy one.

Code wrapped in if (!Meteor.isServer) {...} is removed in the server payload and flattened in the client payload.

Code wrapped in if (!Meteor.isClient) {...} is removed in the client payload and flattended in the server payload.

Code wrapped in if (!Meteor.isCordova) {...} is removed in the cordova payload, and flattened in the server and browser payload.

If Else blocks

if (Meteor.isXX) {...}
else {doSomethingElse();}

Same as If blocks except that Else blocks will remain when the If block is removed. For example, the following code

if (Meteor.isServer) {...}
else {doSomethingElse();}

transforms to this for the client payload:

doSomethingElse();

Else If blocks

if (Meteor.isXX) {...}
else if (...) {doSomethingElse();}
else {doAnythingElse();}

if (...) {...}
else if (Meteor.isXX) {doSomethingElse();}
else {doAnythingElse();}

Else If blocks are also parsed and processed. For example,

if (Meteor.isServer) {doSomething();}
else if (...) {doSomethingElse();}
else {doAnythingElse();}

becomes the following:

// in Server payload
doSomething();

// in Client payload
if (...) {doSomethingElse();}
else {doAnythingElse();}

In another case,

if (...) {doSomething();}
else if (Meteor.isServer) {doSomethingElse();}
else {doAnythingElse();}

becomes the following:

// in Server payload
if (...) {doSomething();}
else {doSomethingElse();}

// in Client payload
if (...) {doSomething();}
else {doAnythingElse();}

How it works

These NPM packages are used:

• esprima
• escodegen

The package parses all files ending with .isojs into ASTs (abstract syntax tree) with esprima. Wrapped nodes are replaced or removed, then the ASTs are parsed back into javascript with escodegen. Source maps are also generated so that line numbers matches when debugging.

Unsupported

• Code in eval statements
• Parser doesn't match now when && || operators are used i.e. if (i > 0 && Meteor.isXX)
• Writing packages with .isojs is untested but should work.
• Doesn't work with CoffeeScript for now