How to make an angular application take arguments from command line? - angularjs

Question

I have an AngularJS application in which my code looks something like this:
myApp = angular.module('myApp',
[
'ui.router',
'ngMaterial',
'ngMessages'
]
);
myApp.constant('CONSTANTS', (function() {
// Define your variable
return {
backend: {
baseURL: 'http://mybackend.com:3026'
}
};
})());
I run this application using http-server on port number 8000 like this:
% http-server -p 8000
I want to pass in a command-line argument for the backend.baseURL such that it over-rides the value specified in the code. How can I do it??

Answer 1

What you need is at least required http-server that supported dynamic content. while your http-server is supported only static content.
And in the comment you asking which server should you use. There are thousands of web-server that support dynamic content out there. but sinc you are currently using http-server I assumed you just want a small server for local-dev.
Unfortunately, I cannot find any server that support your need without modifying their code. So I suggest you to create your own server base on a library on npm.
This is and example server using live-server.
var liveServer = require("live-server");
var fs = require("fs")
var root = process.argv[2] || "."
var port = process.argv[3] || 8000
var replaceTextMiddleWare = function(req, res, next){
var file = process.argv[4]
var find = process.argv[5]
var replace = process.argv[6]
if(file && find){
if(req.url === file) {
fs.readFile( root + file, "utf-8", function(e, content){
res.end( content.replace(find, replace))
} )
return;
}
}
next();
}
var params = {
port: port, // Set the server port. Defaults to 8080.
host: "0.0.0.0", // Set the address to bind to. Defaults to 0.0.0.0 or process.env.IP.
root: root, // Set root directory that's being server. Defaults to cwd.
open: false, // When false, it won't load your browser by default.
ignore: 'scss,my/templates', // comma-separated string for paths to ignore
file: "index.html", // When set, serve this file for every 404 (useful for single-page applications)
wait: 1000, // Waits for all changes, before reloading. Defaults to 0 sec.
mount: [['/components', './node_modules']], // Mount a directory to a route.
logLevel: 2, // 0 = errors only, 1 = some, 2 = lots
middleware: [ replaceTextMiddleWare ] // Takes an array of Connect-compatible middleware that are injected into the server middleware stack
};
liveServer.start(params);
Then you can run your server by
nodejs myserver.js /mydocument/myproject/ 8000 config.js "http://mybackend.com:3026" "http://mydevserver.com:80"
The command accept parameters:
Path to serve content
Port
File name
Text to find
Text to replace
This server support only one dynamic file with simple find/replace.
From this point, I guess you can modify middleware to do whatever you want.

Answer 2

when Ive done this in production I use the build process for this, using gulp in this case,
var knownOptions = {
string: 'env',
default: { env: process.env.NODE_ENV || 'default' }
};
var options = minimist(process.argv.slice(2), knownOptions);
console.log("using config : " + chalk.blue(options.env));
we get an environment variable defaulting to default using minimist we can pass -env 'string'
then further in the code pushing a dynamic file onto app.js
//now we use options.env
appJS.push("env/"+options.env+".js");
env/[options.env].js here is an angular module that exports environment specific constants

Answer 3

looks like you are not using gulp but you are using node script from package.json. if you are using gulp then this should not be a problem you you use http-server via gulp.
one thing you can do in your current case is as part of your run command, set process.env.baseUrl="dynamic" and then roughly speaking, use this in your code like this
return {
backend: {
baseURL:process.env.baseUrl || 'http://fallbackurl'
}

Answer 4

Basically what I understand is that you want to customize http-server package for your won custom handling.
Here is small solution I found for you....
Go to node installation folder(In my case its local one)...
So path of file which we going to edit is like this...
../node_modules/http-server/lib/http-server.js
Import one package which serve you to get command line arguments...you don't need to install it, its already there.
var argv = require('optimist').boolean('cors').argv; // add this line at top after line number 7
Now
At line 60 and after code before.push(function (req, res) { add following code..
if( req.url === '/backend-url' ) {
return res.end(JSON.stringify(argv.x));
}
So before push function will look like::
before.push(function (req, res) {
if( req.url === '/backend-url' ) {
return res.end(JSON.stringify(argv.x));
}
if (options.logFn) {
options.logFn(req, res);
}
res.emit('next');
});
now we have configured our new command line argument x for http-server which will be return for url "/backend-url"
Now at front end
myApp.constant('CONSTANTS', ('$http', function($http) {
// Define your variable
**var backendURL = (function() {
return $http.get('/backend-url', function(bUrl) {
return bUrl;
})
})();**
return {
backend: {
baseURL: backendURL
}
};
})());
Done, now you add url like this: **http-server -p 8080 -x http://example.com**
I choose this approch as replacing file content i dont think good in you case

Answer 5

If you use only one instance of your app, you can start it with script, that accepts all necessary command line arguments, replaces appropriate placeholders (string between specific comments, for example) in your application js files and then launches http-server on necessary port.