In the express docs, there is a section called settings:
http://expressjs.com/api.html#app-settings
But I can't figure out where exactly the should go (to some function? as a dictionary in the use middleware? or somewhere else?)
P.S. How would I go about figure theses things out - do I need to look at source?
There are many ways to manage configuration, but here's a blog post I wrote about it:
http://www.chovy.com/node-js/managing-config-variables-inside-a-node-js-application/
The basic premise is you have a file for each environment (ie config.development.js, config.production.js) and one for everything else called config.global.js the development and production files would simply overwrite whatever you set in the global based on the needs of that environment.
Here’s the basic config/index.js file, this will load the config.test.js file assuming your NODE_ENV=test (we will default to ‘development’ if NODE_ENV is not defined):
var env = process.env.NODE_ENV || 'development'
, cfg = require('./config.'+env);
module.exports = cfg;
Next comes the config.test.js which will include config.global.js and then overwrite it’s json objects as needed:
config.test.js:
var config = require('./config.global');
config.env = 'test';
config.hostname = 'test.example';
config.mongo.db = 'example_test';
module.exports = config;
And the config.global.js which defines all the defaults:
var config = module.exports = {};
config.env = 'development';
config.hostname = 'dev.example.com';
//mongo database
config.mongo = {};
config.mongo.uri = process.env.MONGO_URI || 'localhost';
config.mongo.db = 'example_dev';
Now we wrap it all together and use it in our code…for example in a model, you might do something like this in ./models/user.js:
var mongoose = require('mongoose')
, cfg = require('../config')
, db = mongoose.createConnection(cfg.mongo.uri, cfg.mongo.db);
And that’s all there is to it.
You have to use app.set:
app.set('name of setting', 'value');
You usually put them into a specific configuration block:
app.configure(function () {
// ...
});
You can even use named blocks for having different configurations.
Let express create an application for you and have a look at it. For that simply run
$ express --help
at the command prompt and see what it offers.
PS: This answers both of your questions ;-)
Related
I have a Node + Express app. In many of my files I am doing this at the top
const config = require('./config');
const Twit = require('twit');
const TwitConnector = new Twit(config);
Is there a way to DRY this, so I don't have to repeat this everywhere?
Is there a, best practice, pattern to make something like TwitConnector globally available so that I can use it anytime I need it?
Or maybe that's not a good idea and explicitly requiring it is the right thing to do?
Can't you make twit-connector.js file and require that instead? I don't think making it global is a good idea.
twit-connector.js
const config = require('./config');
const Twit = require('twit');
const TwitConnector = new Twit(config);
module.exports = TwitConnector;
somefile.js
const TwitConnector = require('./twit-connector');
// do something with TwitConnector
In express, I'm trying to move my minification to a requierd file:
app.js:
var app = express();
var minify = require("./minify.js");
In that file I try to set my template engine.
minify.js:
var app = express();
app.engine('html', mustacheExpress());
Later when I try to use to use the rendering engine in app.js, I get the error that no template-engine is set. It works if I run it all in the same file. I think the problem is that I declare the app-variable twice. How can I pass the app-variable into minify.js?
The problem is that you define new app variable, and you currently instantiate brand new express instance by calling express().
What you need to do is start using functions so that you can pass params (there are other methods too, but this is one that will work for you):
// app.js
var app = express();
var minify = require('./minify'); // don't include .js!
minify(app); // CALL the function that minify.js exports, passing params
// minify.js
module.exports = function(app) {
// because app comes as a parameter, it's the very same you've created in app.js
app.engine('html', mustacheExpress());
}
Again, there are many different methods and maybe proper approaches, depending on what you want to do, but this will do the job in your case. Read more about NodeJS and it's require system.
You can pass 'app' from app.js to your minify by using function in your module like Andrey said. You can do it like this too for example :
minify.js
module.exports = {
setAppEngine : function(app) {
app.engine( [...] );
}
}
And calling it like this in your app.js:
app.js
var app = express();
var minify = require("./minify.js").setAppEngine(app);
This solution is very useful because you can set and call others methods in minify.js. For example, you can do with the same code in minify.js:
app.js
var app = express();
var minify = require("./minify.js");
minify.setAppEngine(app);
Node.js is my first backend language and I am at the point where I am asking myself "where do I put the database connection information?".
There is a lot of good information regarding this issue. Unfortunately for me all the examples are in PHP. I get the ideas but I am not confident enough to replicate it in Node.js.
In PHP you would put the information in a config file outside the web root, and include it when you need database data.
How would you do this in Node.js? using the Express.js framework.
So far I have this:
var express = require('express'), app = express();
var mysql = require('mysql');
app.get('/', function(req,res) {
var connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: 'password',
database: 'store'
});
var query = connection.query('SELECT * from customers where email = "deelo42#gmail.com"');
query.on('error', function(err) {
throw err;
});
query.on('fields', function(fields) {
console.log('this is fields');
});
query.on('result', function(row) {
var first = row.first_name;
var last = row.last_name;
res.render('index.jade', {
title: "My first name is " + first,
category: "My last name is " + last
});
});
});
app.listen(80, function() {
console.log('we are logged in');
});
As you can see I have a basic express application with 1 GET route. This route sets off the function to go to the database and pull out information based on an email address.
At the top of the GET route is the database connection information. Where do I put that? How do I call it? How do I keep it out of web root, and include it like PHP ? Can you please show me in a working example. Thanks!
I use the Express Middleware concept for same and that gives me nice flexibility to manage files.
I am writing a detailed answer, which includes how i am use the config params in app.js to connect to DB.
So my app structure looks something this:
How i connect to DB? (I am using MongoDB, mongoose is ORM, npm install mongoose)
var config = require('./config/config');
var mongoose = require("mongoose");
var connect = function(){
var options = {
server: {
socketOptions:{
keepAlive : 1
}
}
};
mongoose.connect(config.db,options);
};
connect();
under the config folder i also have 'env' folder, which stores the environment related configurations in separate files such as development.js, test.js, production.js
Now as the name suggests, development.js stores the configuration params related to my development environment and same applies to the case of test and production. Now if you wish you can have some more configuration setting such as 'staging' etc.
project-name/config/config.js
var path = require("path");
var extend = require("util")._extend;
var development = require("./env/development");
var test = require("./env/test");
var production = require("./env/production");
var defaults = {
root: path.normalize(__dirname + '/..')
};
module.exports = {
development: extend(development,defaults),
test: extend(test,defaults),
production: extend(production,defaults)
}[process.env.NODE_ENV || "development"]
project-name/config/env/test.js
module.exports = {
db: 'mongodb://localhost/mongoExpress_test'
};
Now you can make it even more descriptive by breaking the URL's into, username, password, port, database, hostname.
For For more details have a look at my repo, where you can find this implementation, in fact now in all of my projects i use the same configuration.
If you are more interested then have a look at Mean.js and Mean.io, they have some better ways to manage all such things. If you are beginner i would recommend to keep it simple and get things going, once you are comfortable, you can perform magic on your own. Cheers
I recommend the 12-factor app style http://12factor.net which keeps all of this in env vars. You never should have this kind of information hard-coded or in the app source-code / repo, so you can reuse it in different environments or even share it publicly without breaking security.
However, since there are lots of environment vars, I tend to keep them together in a single env.js like the previous responder wrote - although it is not in the source code repo - and then source it with https://www.npmjs.org/package/dotenv
An alternative is to do it manually and keep it in, e.g. ./env/dev.json and just require() the file.
Any of these works, the important point is to keep all configuration information separate from code.
I agree with the commenter, put it in a config file. There is no ultimate way, but nconf is also one of my favourites.
The important best practise is that you keep the config separate if you have a semi-public project, so your config file will not overwrite other developers.
config-sample.json (has to be renamed and is tracked with for example git)
config.json (not tracked / ignored by git)
I have an express project where I have a directory structure like so,
my-app
routes
index.js
views
public
components
toolbar
test
components
toolbar
Now let's say from my routes I want to require the component toolbar I do it like this
toolbar = require(__dirname + '/../components/toolbar')
Now when I run my test for routes I need to require routes. When I do this I get an error at runtime that toolbar file could not be found.
Is there some global available like say __express_home that I could use in my require so that I would not run into this issue? I would then use it as so,
toolbar = require(__express_home + '/components/toolbar')
You can just do:
toolbar = require('../components/toolbar')
Here is an example from express's github repo.
var express = require('../..')
, app = express()
, site = require('./site')
, post = require('./post')
, user = require('./user');
just use a relative path from wherever you are require() it.
./routes/index.js
./config.js
from ./routes/index.js
var cfg = require('../config');
I'm new in the world of Node.js
According to this topic: What is Node.js' Connect, Express and “middleware”?
I learned that Connect was part of Express
I dug a little in the code, and I found two very interesting files :
./myProject/node_modules/express/lib/utils.js
and better :
./myProject/node_modules/express/node_modules/connect/lib/utils.js
These two files are full of useful functions and I was wondering how to invoke them correctly.
As far, in the ./myProject/app.js, that's what I do:
var express = require('express')
, resource = require('express-resource')
, mongoose = require('mongoose')
, expresstUtils =
require('./node_modules/express/lib/utils.js');
, connectUtils =
require('./node_modules/express/node_modules/connect/lib/utils.js');
But I found it a little clumsy, and what about my others files?
e.g., here is one of my routes:
myResources = app.resource(
'myresources',
require('./routes/myresources.js'));
and here is the content of myresources.js:
exports.index = function(req, res)
{
res.render('./myresources.jade', { title: 'My Resources' });
};
exports.show = function(req, res)
{
fonction resourceIsWellFormatted(param)
{
// Here is some code to determine whether the resource requested
// match with the required format or not
// return true if the format is ok
// return false if not
}
if (resourceIsWellFormatted(req.params['myresources']))
{
// render the resource
}
else
{
res.send(400); // HEY! what about the nice Connect.badRequest in its utils.js?
}
};
As you can see in the comment after the res.send(400), I ask myself if it is possible to use the badRequest function which is in the utils.js file of the Connect module.
What about the nice md5 function in the same file?
Do I have to place this hugly call at the start of my myresources.js to use them?:
var connectUtils =
require('../node_modules/express/node_modules/connect/lib/utils.js');
or, is there a more elegant solution (even for the app.js)?
Thank you in advance for your help!
the only more elegant way i came up with is (assuming express is inside your root "node_modules" folder):
require("express/node_modules/connect/lib/utils");
the node installation is on windows, node version 0.8.2
and a bit of extra information:
this way you don't need to know where you are in the path and be forced to use relative paths (./ or ../), this can be done on any file nesting level.
i put all my custom modules inside the root "node_modules" folder (i named my folder "custom_modules") and call them this way at any level of nesting:
require("custom_modules/mymodule/something")
If you want to access connect directly, I suggest you install connect as a dependency of your project, along with express. Then you can var utils = require('connect').utils.