I'm working through a react with node tutorial and i have some code that looks like this:
if(process.env.UNIVERSAL){
markup = ReactDOMServer.renderToString(...)
.
.
.
}
I understand that process.env stores environment variables but i'm not sure what UNIVERSAL is or where it comes from. I tried to print it out in this code:
const port = process.env.PORT || 3000;
const env = process.env.NODE_ENV || 'production';
server.listen(port, err => {
if (err) {
return console.error(err);
}
console.info(process.env.UNIVERSAL + ' test');
console.info(`Server running on http://localhost:${port} [${env}]`);
});
But it comes out undefined. Any idea what process.env.UNIVERSAL is?
While running a node.js code, you can specify the environment variables. Say for example you have your node.js server in app.js file. You can specify the env parameters while running like
NODE_ENV=development node app.js
for a UNIX environment
or
SET NODE_ENV=development & node app.js
for Windows environment
and then you can access it in your scripts with process.env.NODE_ENV
Similarly you can specify the environment UNIVERSAL while running the script
like
UNIVERSAL=test node app.js
Since you are not specifying anything, you get its value is undefined in the script
Related
I would like to set the NODE_ENV variable at the beginning of a Grunt task, to development or production, but it looks it's not as simple as I thought.
The reason, why I would like this is that I use grunt-webpack, which expects NODE_ENV to be set correctly to "development" or "production". But I also would like to initialize my tasks exclusively from grunt, if possible.
I created the following test Gruntfile, using the grunt-shell and cross-env modules:
function log(err, stdout, stderr, cb, e) {
if (err) {
cb(err);
return;
}
console.log(process.env.NODE_ENV);
console.log(stdout);
cb();
}
module.exports = function(grunt) {
grunt.initConfig({
shell: {
dev: {
command : 'cross-env NODE_ENV="development"',
options: {
callback: log
}
},
dist: {
command : 'cross-env NODE_ENV="production"',
options: {
callback: log
}
}
}
});
grunt.loadNpmTasks('grunt-shell');
};
Line 6 of log() should echo the actual value of process.env.NODE_ENV, but it constantly says undefined, even if I check it manually in the node console.
If I set it manually from the terminal, like set NODE_ENV=production (set is for Windows), everywhere echoes the value production, as I would like it to.
Your test won't work because grunt-shell runs a child_process and your callback runs after it ends and under the main process.
Same thing would happen with cross-env.
If you want to pass an environment variable to grunt-shell, you should use the options configuration according to the documentation.
For example:
grunt.initConfig({
shell: {
dev: {
command : 'echo %NODE_ENV%', //windows syntax
options: {
execOptions: {
env: {
'NODE_ENV': 'dev'
}
},
callback: log
}
}
}
});
This will still print undefined for process.env.NODE_ENV, but the value of NODE_ENV will be available in the stdout because of the echo.
On a side note, it sounds like you're trying to run a process (grunt-shell), which runs a process (cross-env), which runs a process (webpack or grunt-webpack).
Why not just use the cross-env example usage? It looks pretty close to what you need.
Or you can just define the variable in the task config itself and lose all of these wrappers.
LifeQuery's answer helped me a lot to find out what the problem actually was. I first realized that webpack.DefinePlugin() actually doesn't change anything on process.env.NODE_ENV (and it would be too late anyway, as it transforms code parsed by webpack after all loaders).
After this I created a solution, which does what I want. This is how my customized Gruntfile.js begins:
'use strict';
const path = require('path');
const webpack = require('webpack');
module.exports = function (grunt) {
// Setting the node environment based on the tasks's name or target
let set_NODE_ENV = function () {
const devTasks = ['webpack-dev-server', 'dev', 'hmr', 'watch'],
devTargets = [':dev'],
task = grunt.cli.tasks[0], // The name of the (first) task we initialized grunt with ('webpack-dev-server' if started 'grunt webpack-dev-server)
target = ':'+grunt.option('target'),
devEnv = (devTasks.indexOf(task) > -1 || devTargets.indexOf(target) > -1);
process.env.NODE_ENV = devEnv ? 'development' : 'production';
}();
const webpackConfig = require('../assets/webpack.config');
grunt.initConfig({
// ...usual Gruntfile content
});
};
I created a whitelist of grunt task names and targets when I set the process.env.NODE_ENV. As it is placed before the grunt.initConfig(), the configuration object can use process.env.NODE_ENV with the desired state.
It will set NODE_ENV to "development" if starting definitely webpack-dev-server, dev, hmr or watch tasks, or any other tasks with the :dev target.
I am using Gulp / Browserify / Node on Windows, and I want to only include debugging information when in development.
I have a dependant task that is being run before anything else
gulp.task('set-dev-node-env', function() {
process.env.NODE_ENV = 'development'
}
Yet when I try and access this in my code I am finding process.env is an empty object.
console.log("process.env",process.env)
How can I get this to work?
I found a solution was to use envify
var envify = require('envify/custom')
and add it as a transform on my browserify() call
.transform(envify({
NODE_ENV: 'development'
}))
Just migrated on the latest Express, and stuck in something completely simple.
So, how is it possible, that this distilled example:
var env = process.env.NODE_ENV || 'development';
console.log(env);
if ('development' == env) {
console.log('im here');
}
else {
console.log('nah');
console.log(env);
}
with this server file runned as SET NODE_ENV=development & node server.js
gives output:
development
nah
development
instead of
development
im here
By the way, if I'll just manually set var env = 'development' then it work as it should be.
express 4.11.2, node 0.12.0, win8 x64.
I got same problem on windows mode. I'm not sure on linux. This problem caused by spaces between word "development" with "&" character. You can fix by remove spaces on your command. Example:SET NODE_ENV=development& node server.js
Your code looks fine, therefore the reason the equality test must be failing is because the strings aren't equal. Make sure you don't have any extra characters like spaces in your environment variable development string.
same problem, and I find using env.includes('development') instead is okay.
I tried going with the recommendations here but nothing managed to rid me of the wayward space.
so I just trim the variable where it needs to be used:
require('dotenv').config();
const configSet = () => {
const envData = process.env;
console.log('configSet -> process.env', envData);
console.log('configSet -> envData.NODE_ENV', envData.NODE_ENV);
const prodOrDevMode = envData.NODE_ENV.trim();
switch (prodOrDevMode) {
case 'development':
envData.TABLE_NAME = envData.DB_TABLE_DEV;
return envData;
case 'production':
envData.TABLE_NAME = envData.DB_TABLE_PROD;
return envData;
default:
throw new Error('Incorrect env setting');
}
};
const config = configSet();
module.exports = { config };
I'd appreciate any feedback on this in particular if this may cause issues
I have an application that has some development-specific debugging code in it. Currently, all development code is guarded by a variable called dev at the top of the file. Here's an example of what my app does:
var dev = true;
if (dev) {
console.log("Hello developer");
} else {
console.log("Hello production");
}
When I go to deploy my application, I have to manually change the dev variable form true to false. This sucks.
I'm in the middle of migrating from hand-rolled builds to gulp.js and I want to solve this development vs. production build problem cleanly. I'm thinking about the following:
// Inside main.js
var dev = require('./isdev');
if (dev) //...
// Inside isdev.js:
module.exports = true;
Now, when I build for production, instead of manually setting the dev flag to false, I want to replace isdev.js from module.exports = true; to module.exports = false;. My specific question is, how do I automate gulp such that gulp development produces a file with dev = true and gulp production produces a file with dev = false.
Here's an update to those who are curious.
First, I have an options.js:
exports.dev = false;
I also have a options_dev.js:
exports.dev = true;
Inside of gulpfile.js, I have the following code that parses input arguments:
// Parse the arguments. Use `gulp --prod` to build a production extension
var argv = parseArgs(process.argv.slice(2));
var dev = !argv['prod']; // Whether to build a development extension or not
Finally, when I pipe to browserify, I have the following:
var resolve = require('browser-resolve');
// ...
.pipe(browserify({
debug: dev,
resolve: function(pkg, opts) {
// Replace options.js with options_dev.js if this is a dev build
if (dev) {
opts.modules['./options'] = 'src/options_dev.js';
}
return resolve.apply(this, arguments);
}
}))
The magic happens by using a custom resolve function, dynamically swapping ./options with options_dev for development builds. The browserify docs say:
You can give browserify a custom opts.resolve() function or by default it uses browser-resolve.
When we run gulp, we build a development version. When we run gulp --prod, we build a production version. The value of require('./options').dev allows us to dynamically change things like server endpoints, etc. Cool!
The way that I've seen this done is to set the environment variable on the command line before the execution command. An example of doing this with the Node.JS CLI (in a bash-like environment) would be:
ENV=dev node
> process.env.ENV
'dev'
Then in your code, you could do:
var dev = process.env.ENV === 'dev'
So with gulp, you could use:
ENV=dev gulp <task name>
I tested this out with the following snippet, and it works:
gulp.task('dev', function(){
if (process.env.ENV === 'dev')
console.log("IT WORKED");
else
console.log("NO DICE");
});
Edit:
You can write out the environment to the file isdev right before building:
var fs = require('fs');
gulp.task('build', function(){
if (process.env.ENV === 'dev')
fs.writeFileSync('isdev', 'module.exports = true');
else
fs.writeFileSync('isdev', 'module.exports = false');
// kick off build
});
Now, the correct value will be present in isdev for any require call in the built bundle. You could extend this to other specified environments as well (or to other configuration flags).
I created a simple Webapp using express.js and want to test it with jasmine-node. Works fine so far but my problem is that I have to start the server manually every time before I can run my tests.
Could you help me on how to write a spec-helper that runs the server (with another port then my development one) just for the tests and then kills it afterwards?
This is what I do:
I have a server.js file inside the root of my node project that sets up the node application server (with express) and exports 2 methods:
exports.start = function( config, readyCallback ) {
if(!this.server) {
this.server = app.listen( config.port, function() {
console.log('Server running on port %d in %s mode', config.port, app.settings.env);
// callback to call when the server is ready
if(readyCallback) {
readyCallback();
}
});
}
};
exports.close = function() {
this.server.close();
};
The app.js file will be simple at this point:
var server = require('./server');
server.start( { port: 8000 } );
So the files/folder basic structure would be the following:
src
app.js
server.js
Having this separation will allow you to run the server normally:
node src/app.js
..and/or require it from a custom node script, which could be a node script (or a jake/grunt/whatever task) that executes your tests like this:
/** my-test-task.js */
// util that spawns a child process
var spawn = require('child_process').spawn;
// reference to our node application server
var server = require('./path/to/server.js');
// starts the server
server.start( { port: 8000 }, function() {
// on server ready launch the jasmine-node process with your test file
var jasmineNode = spawn('jasmine-node', [ '.path/to/test/file.js' ]);
// logs process stdout/stderr to the console
function logToConsole(data) {
console.log(String(data));
}
jasmineNode.stdout.on('data', logToConsole);
jasmineNode.stderr.on('data', logToConsole);
jasmineNode.on('exit', function(exitCode) {
// when jasmine-node is done, shuts down the application server
server.close();
}
});
I use Mocha - which is damn similar - but the same principle should apply: you could try requireing your app.js file in a 'beforeEach' hook inside the main describe. That should fire it up for you.
Assuming you use some code that invokes app.listen() in server.js, don't require the file on each run but only once and then have two functions like
startServer = -> app.listen(3000)
stopServer = -> app.close()
Then you can use these in beforeEach and afterEach
If you want then to go one step further in automating your testing while you develop, you can go to your terminal line and execute
jasmine-node . --autotest
Jasmine then will stay listening to every file inside your project and whenever you make changes to one it will tell if that piece of your code breaks any of your tests ;)