How to set global variables by command - node.js

Question

Thanks for so many fast response.
I used NodeJS(v4.3.2) and ExpressJs(v4.x) to build up website.
I used a lot AJAX and all AJAX url point to one static IP(AWS Server itself).
Because I would deploy to several servers, I don't want to change AJAX url separately.
My idea is when I run "node bin/www" command line, Can I change it to "node bin/www 50.50.50.50(my AWS address)" and I can set all AJAX url to the right IP?
Is it possible or other alternative solustion?
Thanks

Answer 1

Your issue is related to CORS : basically, you cannot access a domain http://www.example1.com from http://www.example2.com via Ajax if http://www.example1.com does not explicitly allows it in the response.
This is a "security" feature on most modern browsers. You won't encounter this problem using command line such as curl or chrome extension Postman.
To fix this, make sure the domain requesting the data (http://www.example2.com) is allowed in the Access-Control-Allow-Origin header in your server's response, as well as the http verb (GET, POST, PUT... or * for every http methods).
It all comes down to add the two following headers to the http://www.example1.com server's response :
Access-Control-Allow-Origin: http://www.example2.com
Access-Control-Allow-Methods: *
Edit
Following #Paulpro's comment, you have to rebase all your urls so that they reach your server's IP instead of your localhost server.

Answer 2

I fix this problem.
First, in bin/www
append these code to retrieve URL for command line and store into json file.
function setUpURL(){
var myURL = process.argv[2];
console.log('myURL: ', myURL);
var outputFilename = 'public/myURL.json';
var myData = {
port:myURL
}
fs.writeFile(outputFilename, JSON.stringify(myData, null, 4), function(err) {
if(err) {
console.log(err);
} else {
console.log("JSON saved to " + outputFilename);
}
});
};
Then in each JS containing ajax add these code in the head of JS file (it need to load before ajax)
var myURL;
$.getJSON("myURL.json", function(json) {
myURL = json.port.toString();
console.log(myURL);
});
new ajax format
$.ajax({
type: "POST",
url: myURL + "/forgetPwd",
data: sendData,
success: function(data){
window.location.replace(myURL);
},
error: function(data){
}
});
Finally, you can run server
node bin/www your_aws_ip
It works for me now. Hope these will help you guys.
By the way, you should be careful about the path of myURL.json.