How to validate null, undefined, and empty strings in a single way
if (string_type_variable) { }
Category: expressJS
Node js deployment with PM2 Clustering
When it comes to Node js clustering no need to do any modification in node js appliation but it depends on the deployment command in PM2.
ex: appStart.js
var http = require('http');
http.createServer(function(req, res) {
res.writeHead(200);
res.end("PM2 clustering test\n");
}).listen(8080); deployment command: pm2 start appStart.js -i 3//The above command will start 3 instance of processes instances of fork .
Have you ever thought about clustering vs Forking ?
ENV setup in node
process.env is a reference to your environment, so you have to set the variable there.
To set an environment variable in Windows:
SET NODE_ENV=developmenton OS X or Linux:
export NODE_ENV=developmentMongodb concatenation
How to replace SQL concatenation in mongoDB
example in SQL:
SELECT CONCAT(firstName, ” “, lastName) AS fullName
FROM Customers WHERE concat(firstName, " ", lastName) = 'value'
;
MongoDB:
in below 3.6
db.coll.aggregate({$match:{firstName:/^val/}},
{$project:{newField:{$concat:["$firstName","$lastName"]}}},
{$match:{newField:"value"}}
);please consider to index firstName, wich will improve performance .
in 3.6 or above :
db.coll.find({$expr:{$eq:["value", {$concat:["$firstName", "$lastName"]}]}})
Sample Lamda function for Alexa skill using Nodejs
I got an opportunity to work on Alexa skill using NodeJs and am willing to share the thing that i learnt .
official URL for setup:https://developer.amazon.com/alexa-skills-kit/alexa-skill-python-tutorial
In this session which focuses on to write Lamda function and how to link it with Alexa skill.
Outcomes:
Alexa skill creation
Lamda function
configuration and setup
Create Alexa skills
Log into https://developer.amazon.com and create a skillset.
configuration and setup:
github url:https://github.com/azeemj/alexa-skillset/blob/master/index.js
Screen shots
NodeJS API (ExpressJS) for beginners with AWS setup
(
Node.js is a very powerful JavaScript-based framework/platform built on Google Chrome’s JavaScript V8 Engine. It is used to develop I/O intensive web applications like video streaming sites, single-page applications, and other web applications. Node.js is open source, completely free.
Prerequisites
Before proceeding with this tutorial, you should have a basic understanding of JavaScript.
What is Node.js?
Node.js is a server-side platform built on Google Chrome’s JavaScript Engine .
Features of Node.js
Following are some of the important features that make Node.js the first choice of software architects.
- Asynchronous and Event Driven
- Very Fast− Being built on Google Chrome’s V8 JavaScript Engine, Node.js library is very fast in code execution.
- Single Threaded but Highly Scalable− Node.js uses a single threaded model with event looping.
- No Buffering− Node.js applications never buffer any data. These applications simply output the data in chunks.
- License− Node.js is released under the MIT license.
Node.js better results
Following are the areas where Node.js is proving itself as a perfect technology partner.
- I/O bound Applications
- Data Streaming Applications
- Data Intensive Real-time Applications (DIRT)
- JSON APIs based Applications
- Single Page Applications
Environment setup:
Use the MSI file and follow the prompts to install the Node.js. By default, the installer uses the Node.js distribution in C:\Program Files\nodejs. The installer should set the C:\Program Files\nodejs\bin directory in window’s PATH environment variable. Restart any open command prompts for the change to take effect.
Linux :
$ cd /tmp
$ wget http://nodejs.org/dist/v6.3.1/node-v6.3.1-linux-x64.tar.gz
$ tar xvfz node-v6.3.1-linux-x64.tar.gz
$ mkdir -p /usr/local/nodejs
$ mv node-v6.3.1-linux-x64/* /usr/local/nodejs
Add /usr/local/nodejs/bin to the PATH environment variable.
| OS | Output |
| Linux | export PATH=$PATH:/usr/local/nodejs/bin |
| Mac | export PATH=$PATH:/usr/local/nodejs/bin |
| FreeBSD | export PATH=$PATH:/usr/local/nodejs/bin |
Node Package Manager (NPM) provides two main functionalities −
- Online repositories for node.js packages/modules which are searchable onnodejs.org
- Command line utility to install Node.js packages, do version management and dependency management of Node.js packages.
- $ npm –version
$ sudo npm install npm -g
/usr/bin/npm -> /usr/lib/node_modules/npm/bin/npm-cli.js
npm@2.7.1 /usr/lib/node_modules/npm
Install Express:
- https://github.com/petecoop/generator-express , install express generator MVC
- express test
- open project in editor
Server deployment
npm install pm2 –g
pm2 start app.js
Install mongo admin tool
check the express.js to customize for APi
app.use(function (req, res, next) {
var err = new Error('Not Found');
err.status = 404;
var chk =req.path;
if( chk.indexOf('api') >= 0){
return res.json( {
message: err.message,
success:false
});
}
});
or
app.use(function (req, res, next) {
var err = new Error('Not Found');
err.status = 404;
var chk =req.path;
if( chk.indexOf('api') >= 0){
return res.json( {
message: err.message,
success:false
});
}else{
res.render('error', {
message: err.message,
error: {},
title: 'error'
});
}
});
home.jS
please add the following lib for JSON actions with prefixed router
var webrouter = express.Router();
var bodyParser = require('body-parser');
var app = express();
var util = require('util');
var multer = require('multer')
//var http = require('http').Server(app);
var jsonParser = bodyParser.json()
app.use(bodyParser.urlencoded({ extended: true }))
app.use(bodyParser.json());
module.exports = function (app) {
app.use('',router);
app.use('/api/v1', webrouter);
};
keep the following function for uncaught exception handling
process.on('uncaughtException', function (err) {
console.log('uncaughtException: ' + err.message);
console.log(err.stack);
});
Simple API with prefix
webrouter.post('/add-article', function (req, res, next) {
user=10;
return res.json({
success: true,
content: {message: 'artilce added success',
result: user}
});
});
Common area for authentication purposes.
webrouter.use(function (req, res, next) {
// check header or url parameters or post parameters for token
var token = req.body.token || req.query.token || req.headers['token'];
//get last parameter
var requested_url = req.path;
console.log(requested_url);
if (token) {
//some processing
console.log("common area with token")
next()
}
else if (req.path == "/signup")
{
next();
}else{
console.log("common area with non token")
var err = new Error('Not Found');
console.log(req.path);
return res.status(403).send({
success: false,
content: {message: 'No token provided.'}
});
}
});
webrouter.post('/signup', function (req, res, next) {
return res.json({success: false, content: {message:"signup"}});
});
Simple saving function to store student records
create a student model ,student.js
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var StudentSchema = new Schema({
title: String,
url: String,
text: String,
id:Number
});
mongoose.model('Student', StudentSchema);
include this model into home.JS
var Student = mongoose.model('Student')
Make a route
webrouter.post('/add-student', function (req, res) {
title=req.body.title;
id=req.body.id;
Student=new Student();
Student.title=title;
Student.id=id;
Student.save(function (err, row) {
if(err){
return res.json({
success: false,
content: {message: 'student is not added',
result: err}
});
}else{
return res.json({
success: true,
content: {message: 'student added success',
result: row}
});
}
});
});
Simple get function by ID and updating
webrouter.post('/update-student', function (req, res) {
console.log(req.body.id);
if (!req.body.id)
return res.json({success: false, content: {message: "Please enter the id."}});
if (!req.body.text)
return res.json({success: false, content: {message: "Please enter the text."}});
Student.findOne({"id": req.body.id}, function (err, student) {
console.log(student);
if (err) {
return res.json({success: false,
content: {message: 'student is not found'},
result: err});
//check the firstname and last name are exist or not
}
else if (student)
{
student.text = req.body.text;
student.save(function (err, row) {
if (err) {
return res.json({success: false,
content: {message: 'student is not found'},
result: err});
} else {
return res.json({
success: true,
content: {message: 'student added success',
result: row}
});
}
});
return res.json({success: true,
content: {message: 'student found'},
result: student});
} else {
return res.json({success: false,
content: {message: 'null'},
result: null});
}
});
});
Example for asyncrinus function
Import the lib (on top of the page),
var async = require('async');
webrouter.post('/async-example', function (req, res) {
var async = require('async');
async.parallel({
one: function(callback) {
callback(null, 'abc\n');//first parameter is error ,second is returning
},
two: function(callback) {
callback(null, 'xyz\n');
}
}, function(err, results) {
// results is now equals to: {one: 'abc\n', two: 'xyz\n'}
console.log(err);
console.log(results.two);
return res.json({success: true,
content: {message: 'async example '},
result: results});
});
});
Simple callback function
webrouter.post('/example-callback', function (req, res) {
a="test1";
b="exam";
concatenation(a,b,function(results){
if(results){
return res.json({success: true,
content: {message: 'example-callback'},
result: results});
}else{
return res.json({success: true,
content: {message: 'example-callback'},
result: results});
}
})
})
function concatenation(a,b,callback){
if(a!=""){
var c=a+b;
console.log("aftfer c")
callback(c) ;
}else{
callback(null);
}
}
//async foreach to keep on tracking
var forEach = require('async-foreach').forEach;
//get one stduent and one article set
Topics:
- Authentication with web token
- Signup and login
- Token usage for resources
- API with auth and without auth
- API access data after checking the updated version
- maintain history table to maintain big data
- cache for making fast API responses
- Installation and deployment
- Authentication with web token
There are some situation for open API access(wihtout AUTH ) as well as with AUTH.
with AUTH:
import the following libraries
//start
var bcrypt = require('bcrypt');
var jwt = require('jsonwebtoken');
var User = mongoose.model('User');
var Client = mongoose.model('clients');
var Accesstoken = mongoose.model('auth_accesstokens');
//end
then
//common routing architecture
webrouter.use(function (req, res, next) {
// check header or url parameters or post parameters for token
var token = req.body.token || req.query.token || req.headers['token'];
//get last parameter
var requested_url = req.path;
var requested_url_array = requested_url.split('/');
var lastsegment = requested_url_array[requested_url_array.length - 1];
console.log(lastsegment);
if (token) {
//some processing
jwt.verify(token, 'ilovescotchyscotch', function (err, decoded) {
if (err) {
return res.json({success: false, content: {message:"auth failed1"}});
} else {
// if everything is good, save to request for use in other routes
var apikey = req.body.apikey || req.query.apikey || req.headers['apikey'];
Accesstoken.count({$and: [{'token': token}, {'user_id': req.headers.user_id}, {'clientId': apikey}]}, function (err, clientdata) {
if (clientdata == 0) {
return res.json({success: false, content: {message: "auth failed2"}});
} else {
req.decoded = decoded;
next();
}
}
);
}
});
} else {
console.log("common area with non token")
if (req.path == "/authentication" || req.path == "/signup"
|| req.path == "/logout" || req.path =="/add-apikey") {
next();
} else {
var err = new Error('Not Found');
console.log(req.path);
return res.status(403).send({
success: false,
content: {message: 'No token provided.'}
});
return res.status(404).send({
success: false,
content: {message: 'Page not found.'}
});
}
}
});
Register API auth related models
models:
var User = mongoose.model('User');
var Client = mongoose.model('clients');
var Accesstoken = mongoose.model('auth_accesstokens');
Then add the api key:
webrouter.get('/add-apikey', function (req, res) {
client = Client();
client.name = "webrouter";
client.clientId = "heRueI9SA";
client.clientSecret = "heRueI9SAsecretAA";
client.save(function (err, row) {
if (err) {
return res.json({
success: false,
content: {message: 'add-apikey is not added',
result: err}
});
} else {
return res.json({
success: true,
content: {message: 'add-apikey added success',
result: row}
});
}
});
});
signup process:
webrouter.post('/signup', function (req, res, next) {
if (!req.headers.fname)
return res.json({success: false, content: {message: "Please enter the name."}});
if (!req.headers.lname)
return res.json({success: false, content: {message: "Please enter the last name."}});
if (!req.headers.email)
return res.json({success: false, content: {message: "Please enter the email."}});
if (!req.headers.password)
return res.json({success: false, content: {message: "Please enter the password."}});
console.log("muy test2")
clientId = req.headers.apikey;
User.findOne({'email': req.headers.email}, {type: 0}, function (err, user) {
console.log("inside user"+user)
// if there are any errors, return the error
if (err)
return res.json({success: false, content: {message: err}});
// check to see if theres already a user with that email
if (user) {
console.log("success: false");
return res.json({success: false, content: {message: 'The email is already registered.'}, newuser: 0});
}
else {
Client.findOne({clientId: clientId}, function (err, client) {
if (err)
return res.json({success: false, content: {message: "Wrong API key"}});
console.log(client);
if (!client) {
return res.json({success: false, content: {message: "Wrong API key"}});
}
var user = new User();
var pass;
createHash(req.headers.password,function(pas){
pass=pas;
console.log("pass"+pass)
user.email = req.headers.email;
user.password = pass
user.firstName = req.headers.fname;
user.lastName = req.headers.lname;
user.save(function (err) {
if (err){
return res.json({success: false, content: {message: err}});
} else {
console.log("{message: 'Authentication success'");
return res.json({
success: true,
content: {message: 'Authentication success',
result: user}
});
}
//return res.json({success: true, content: {message: "Signup sucessfully."}});
});
});
});
} // We're not logged in, so we're creating a brand new user.
});
}
);
Note:when u return please avoid to return the encrypted password
auth related functions
function createHash(password,callback){
saltRounds = 10;
console.log("password"+password);
//return bcrypt.hashSync(password, bcrypt.genSaltSync(8), null);
bcrypt.genSalt(saltRounds, function(err, salt) {
bcrypt.hash(password, salt, function(err, hash) {
// Store hash in your password DB.
console.log("out"+hash);
callback(hash);
});
});
}
// checking if password is valid
function validPassword(password,hash,callback) {
// return bcrypt.compareSync(password, this.password);
console.log(password);
console.log(hash);
bcrypt.compare(password, hash, function(err, res) {
// res == true
console.log(res);
callback(res);
});
};
authentications
webrouter.post('/authentication', function (req, res) {
var clientId = req.headers.apikey
if (!req.headers.device)
return res.json({success: false, content: {message: "Please send the device token."}});
if (!req.headers.apikey)
return res.json({success: false, content: {message: "Please send the API key."}});
if (!req.headers.email)
return res.json({success: false, content: {message: "Please send the user email."}});
if (!req.headers.password)
return res.json({success: false, content: {message: "Please send the password."}});
Client.findOne({clientId: clientId}, function (err, client) {
if (err)
return res.json({success: false, content: {message: "Wrong API key"}});
console.log(client);
if (!client) {
return res.json({success: false, content: {message: "Wrong API key"}});
}
User.findOne({'email': req.headers.email}, function (err, user) {
//console.log("test");process.exit();
if (err)
throw err;
if (!user) {
console.log("three");
return res.json({success: false, content: {message: 'Authentication failed. User not found.'}});
} else if (user) {
password = req.headers.password;
username = req.headers.email;
console.log("password"+password)
console.log("user.password"+user.password)
try {
validPassword(password, user.password,function(result){
if (!result) {
// if password does not match
return res.json({success: false, content: {message: "Wrong password"}});
} else {
// if everything is OK, return null as the error // and the authenticated user
con_cat = req.headers.device + '' + req.headers.email
var token = jwt.sign(con_cat, 'ilovescotchyscotch');
var accesstok = new Accesstoken({
'clientId': clientId, "token": token, "device_token": req.headers.device, 'ip': '198.168.1.20', 'os': "ios", 'user_id': user._id
});
Accesstoken.findOne({$and: [{'device_token': req.headers.device}, {'user_id': user._id}]}, function (err, checkaccesstoken) {
if (err)
throw err;
if (!checkaccesstoken)
{
accesstok.save(function (err, row) {
if (err)
throw err;
// return the information including token as JSON
return res.json({
success: true,
content: {message: 'Authentication success',
token: token,
result: user}
});
});
} else {
checkaccesstoken.clientId = clientId;
checkaccesstoken.token = token;
checkaccesstoken.device_token = req.headers.device_token;
checkaccesstoken.ip = '198.168.1.20';
checkaccesstoken.os = "ios";
checkaccesstoken.user_id = user._id;
checkaccesstoken.save(function (err, row) {
if (err)
throw err;
// return the information including token as JSON
return res.json({
success: true,
content: {message: 'Authentication success',
token: token,
result: user}
});
});
}
});
}
});
} catch (e) {
return res.json({success: false, content: {message: "Wrong password"+e}});
}
}
});
});
});
Redis-cache
before access the API check the version number to make sure the data update
//initializing radis connection
var options = {
ttl: -1,
engine: 'redis',
port: 6379,
host: 'localhost'
};
//create an instacne
var Cacheman = require('cacheman');
var cache2 = new Cacheman('todo', options);
webrouter.post('/add-top-news', function (req, res, next) {
user = 10;
console.log(req.body);
var data={
success: true,
content: {message: 'add-top-news success',
result: user}
}
cache2.set('add-top-news', data)
.then(function (value) {
return res.json({
success: true,
content: {message: 'artilce added success',
result: user}
});
});
});
webrouter.get('/get-top-news', function (req, res, next) {
user = 10;
console.log(req.body);
cache2.get('add-top-news', function (err, value) {
if (err)
throw err;
console.log(value);
return res.json({
success: true,
content: {message: 'artilce added success',
result: value}
});
});
});
Redis command:redis 127.0.0.1:6379> keys *
Deployment
Development simple:
Enhanced
For source code :https://github.com/azeemj/nodeJS-API-auth
Node.js and Nginx on an Amazon Linux EC2 Instance
(from:http://thomasmullaly.com/2014/11/02/node-dot-js-and-nginx-on-an-amazon-linux-ec2-instance/)
I’m looking to automate a node.js application on amazon web services. I’m using the amazon linux ami, which is based off of centos 5. Notice that amazon has switched from using para-virtualized (pv) guests to hardware virtualized machine guests (hvm).
Launch the instance and ssh in, and become root (sudo -i). Now install nginx
[ec2-user@ip-172-30-0-164 ~]$ sudo !!
sudo yum install nginx
Loaded plugins: priorities, update-motd, upgrade-helper
amzn-main/latest | 2.1 kB 00:00
amzn-updates/latest | 2.3 kB 00:00
Resolving Dependencies
--> Running transaction check
---> Package nginx.x86_64 1:1.6.2-1.22.amzn1 will be installed
--> Processing Dependency: gd for package: 1:nginx-1.6.2-1.22.amzn1.x86_64
--> Processing Dependency: GeoIP for package: 1:nginx-1.6.2-1.22.amzn1.x86_64
--> Processing Dependency: libprofiler.so.0()(64bit) for package: 1:nginx-1.6.2-1.22.amzn1.x86_64
--> Processing Dependency: libGeoIP.so.1()(64bit) for package: 1:nginx-1.6.2-1.22.amzn1.x86_64
--> Processing Dependency: libgd.so.2()(64bit) for package: 1:nginx-1.6.2-1.22.amzn1.x86_64
--> Running transaction check
---> Package GeoIP.x86_64 0:1.4.8-1.5.amzn1 will be installed
---> Package gd.x86_64 0:2.0.35-11.10.amzn1 will be installed
--> Processing Dependency: libXpm.so.4()(64bit) for package: gd-2.0.35-11.10.amzn1.x86_64
---> Package gperftools-libs.x86_64 0:2.0-11.5.amzn1 will be installed
--> Processing Dependency: libunwind.so.8()(64bit) for package: gperftools-libs-2.0-11.5.amzn1.x86_64
--> Running transaction check
---> Package libXpm.x86_64 0:3.5.10-2.9.amzn1 will be installed
---> Package libunwind.x86_64 0:1.1-2.1.amzn1 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
============================================================================================================
Package Arch Version Repository Size
============================================================================================================
Installing:
nginx x86_64 1:1.6.2-1.22.amzn1 amzn-updates 523 k
Installing for dependencies:
GeoIP x86_64 1.4.8-1.5.amzn1 amzn-main 783 k
gd x86_64 2.0.35-11.10.amzn1 amzn-main 155 k
gperftools-libs x86_64 2.0-11.5.amzn1 amzn-main 570 k
libXpm x86_64 3.5.10-2.9.amzn1 amzn-main 54 k
libunwind x86_64 1.1-2.1.amzn1 amzn-main 69 k
Transaction Summary
============================================================================================================
Install 1 Package (+5 Dependent packages)
Total download size: 2.1 M
Installed size: 4.8 M
Is this ok [y/d/N]: y
Downloading packages:
(1/6): GeoIP-1.4.8-1.5.amzn1.x86_64.rpm | 783 kB 00:00
(2/6): gd-2.0.35-11.10.amzn1.x86_64.rpm | 155 kB 00:00
(3/6): gperftools-libs-2.0-11.5.amzn1.x86_64.rpm | 570 kB 00:00
(4/6): libXpm-3.5.10-2.9.amzn1.x86_64.rpm | 54 kB 00:00
(5/6): libunwind-1.1-2.1.amzn1.x86_64.rpm | 69 kB 00:00
(6/6): nginx-1.6.2-1.22.amzn1.x86_64.rpm | 523 kB 00:00
------------------------------------------------------------------------------------------------------------
Total 15 MB/s | 2.1 MB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : libXpm-3.5.10-2.9.amzn1.x86_64 1/6
Installing : gd-2.0.35-11.10.amzn1.x86_64 2/6
Installing : libunwind-1.1-2.1.amzn1.x86_64 3/6
Installing : gperftools-libs-2.0-11.5.amzn1.x86_64 4/6
Installing : GeoIP-1.4.8-1.5.amzn1.x86_64 5/6
Installing : 1:nginx-1.6.2-1.22.amzn1.x86_64 6/6
Verifying : gperftools-libs-2.0-11.5.amzn1.x86_64 1/6
Verifying : GeoIP-1.4.8-1.5.amzn1.x86_64 2/6
Verifying : 1:nginx-1.6.2-1.22.amzn1.x86_64 3/6
Verifying : gd-2.0.35-11.10.amzn1.x86_64 4/6
Verifying : libunwind-1.1-2.1.amzn1.x86_64 5/6
Verifying : libXpm-3.5.10-2.9.amzn1.x86_64 6/6
Installed:
nginx.x86_64 1:1.6.2-1.22.amzn1
Dependency Installed:
GeoIP.x86_64 0:1.4.8-1.5.amzn1 gd.x86_64 0:2.0.35-11.10.amzn1 gperftools-libs.x86_64 0:2.0-11.5.amzn1
libXpm.x86_64 0:3.5.10-2.9.amzn1 libunwind.x86_64 0:1.1-2.1.amzn1
Complete!Make sure nginx starts up on a reboot:
sudo chkconfig --level 345 nginx onNow Let’s install node.js
[root@ip-172-30-0-164 ~]# curl -sL https://rpm.nodesource.com/setup | bash -
## Inspecting system...
+ rpm -q --whatprovides redhat-release
+ uname -m
## Confirming "el7-x86_64" is supported...
+ curl -sLf -o /dev/null 'https://rpm.nodesource.com/pub/el/7/x86_64/nodesource-release-el7-1.noarch.rpm'
## Downloading release setup RPM...
+ mktemp
+ curl -sL -o '/tmp/tmp.tGqnuw1nK9' 'https://rpm.nodesource.com/pub/el/7/x86_64/nodesource-release-el7-1.noarch.rpm'
## Installing release setup RPM...
+ rpm -i --nosignature --force '/tmp/tmp.tGqnuw1nK9'
## Cleaning up...
+ rm -f '/tmp/tmp.tGqnuw1nK9'
## Checking for existing installations...
+ rpm -qa 'node|npm' | grep -v nodesource
## Run `yum install -y nodejs` (as root) to install Node.js and npm.
## You may also need development tools to build native addons:
## `yum install -y gcc-c++ make`
[root@ip-172-30-0-164 ~]# yum install -y nodejs
Loaded plugins: priorities, update-motd, upgrade-helper
nodesource/x86_64 | 2.4 kB 00:00
nodesource/x86_64/primary_db | 7.9 kB 00:00
Resolving Dependencies
--> Running transaction check
---> Package nodejs.x86_64 0:0.10.33-1nodesource.el7.centos will be installed
--> Finished Dependency Resolution
Dependencies Resolved
============================================================================================================
Package Arch Version Repository Size
============================================================================================================
Installing:
nodejs x86_64 0.10.33-1nodesource.el7.centos nodesource 4.5 M
Transaction Summary
============================================================================================================
Install 1 Package
Total download size: 4.5 M
Installed size: 15 M
Downloading packages:
warning: /var/cache/yum/x86_64/latest/nodesource/packages/nodejs-0.10.33-1nodesource.el7.centos.x86_64.rpm: Header V3 RSA/SHA1 Signature, key ID 34fa74dd: NOKEY
Public key for nodejs-0.10.33-1nodesource.el7.centos.x86_64.rpm is not installed
nodejs-0.10.33-1nodesource.el7.centos.x86_64.rpm | 4.5 MB 00:00
Retrieving key from file:///etc/pki/rpm-gpg/NODESOURCE-GPG-SIGNING-KEY-EL
Importing GPG key 0x34FA74DD:
Userid : "NodeSource <gpg-rpm@nodesource.com>"
Fingerprint: 2e55 207a 95d9 944b 0cc9 3261 5ddb e8d4 34fa 74dd
Package : nodesource-release-el7-1.noarch (installed)
From : /etc/pki/rpm-gpg/NODESOURCE-GPG-SIGNING-KEY-EL
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
Installing : nodejs-0.10.33-1nodesource.el7.centos.x86_64 1/1
Verifying : nodejs-0.10.33-1nodesource.el7.centos.x86_64 1/1
Installed:
nodejs.x86_64 0:0.10.33-1nodesource.el7.centos
Complete!Now install pm2 which is the daemon which runs the node server.
[root@ip-172-30-0-164 ~]# npm install pm2 -g --unsafe-perm
|
> pm2@0.11.1 preinstall /usr/lib/node_modules/pm2
> bash ./scripts/preinstall.sh
npm_config_argv={"remain":["pm2"],"cooked":["install","pm2","--global","--unsafe-perm"],"original":["install","pm2","-g","--unsafe-perm"]}
npm WARN optional dep failed, continuing fsevents@0.3.0
/usr/bin/pm2 -> /usr/lib/node_modules/pm2/bin/pm2
> pm2@0.11.1 postinstall /usr/lib/node_modules/pm2
> bash ./scripts/postinstall.sh
pm2@0.11.1 /usr/lib/node_modules/pm2
├── ikt@0.0.0
├── uid-number@0.0.5
├── json-stringify-safe@5.0.0
├── commander@2.3.0
├── eventemitter2@0.4.14
├── pm2-interface@2.0.4
├── colors@0.6.2
├── cron@1.0.4
├── cli-table@0.3.0
├── pidusage@0.1.0
├── async@0.9.0
├── axm@0.2.13
├── vizionar@0.1.3
├── chokidar@0.9.0 (recursive-readdir@0.0.2)
├── debug@2.0.0 (ms@0.6.2)
├── pm2-multimeter@0.1.2 (charm@0.1.2)
├── pm2-deploy@0.1.2 (tv4@1.0.18)
├── nssocket@0.5.1 (lazy@1.0.11)
├── chalk@0.5.1 (escape-string-regexp@1.0.2, ansi-styles@1.1.0, supports-color@0.2.0, strip-ansi@0.3.0, has-ansi@0.1.0)
├── punt@2.2.0 (amp-message@0.1.2)
├── pm2-axon-rpc@0.3.6 (commander@1.0.5)
├── pm2-axon@2.0.7 (amp-message@0.1.2, escape-regexp@0.0.1, configurable@0.0.1, amp@0.3.1)
├── pm2-rpc-fallback@3.0.9 (commander@1.0.5, axon@1.0.0)
├── coffee-script@1.8.0 (mkdirp@0.3.5)
├── pm2-logs@0.1.1 (chalk@0.4.0, pm2-interface@1.1.0, blessed@0.0.36)
└── moment@2.8.3create a simple node.js server, create a file called server.js
var http = require('http');
var server = http.createServer(function (request, response) {
response.writeHead(200, {"Content-Type": "text/plain"});
response.end("Hello World\n");
});
server.listen(8080);
console.log("Server running at http://127.0.0.1:8080/");You can try out the server by starting it like this:
[ec2-user@ip-172-30-0-164 ~]$ node server.js
Server running at http://127.0.0.1:8080/Or you can daemonize it with pm2, like this:
[ec2-user@ip-172-30-0-164 ~]$ pm2 start server.js
Initializing PM2 configuration (/home/ec2-user/.pm2)
Starting PM2 daemon...
[PM2] Process server.js launched
┌──────────┬────┬──────┬──────┬────────┬───────────┬────────┬────────────┬─────────────┐
│ App name │ id │ mode │ PID │ status │ restarted │ uptime │ memory │ watching │
├──────────┼────┼──────┼──────┼────────┼───────────┼────────┼────────────┼─────────────┤
│ server │ 0 │ fork │ 1257 │ online │ 0 │ 0s │ 9.922 MB │ unactivated │
└──────────┴────┴──────┴──────┴────────┴───────────┴────────┴────────────┴─────────────┘
Use `pm2 desc[ribe] ` to get more detailsNow let’s add the proxy info to nginx, edit /etc/nginx/nginx.conf
server {
listen 80;
#server_name localhost;
server_name your-ip-address;
root /usr/share/nginx/html;
#charset koi8-r;
#access_log /var/log/nginx/host.access.log main;
location / {
proxy_pass http://localhost:8080;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_cache_bypass $http_upgrade;
}restart nginx
sudo service nginx restarthit the ip address with a browser and you should see “hello world”
AWS Polly with Node JS
Hi,
I got a chance to work with AWS Polly and i am willing to share my interesting experiences.
Amazon Polly (Text-to-Speech) implementation with Node JS
What is Amazon Polly?
Amazon Polly is a mechanism that gives text-to-speech cloud service. Amazon Polly supports multiple languages and includes a variety of voices.
Benefits:
- High quality
- Low latency
- Support for different voices
- Cost effective
- Cloud based solution
Architecture of AWS Polly implementation.
Coding level implementation
Node js Function
//initilaization
var fs = require(‘fs’);
var AWS = require(‘aws-sdk’);
require(‘ auth-config-polly.js’);
function PollyImplemetation(req, callback) {
var msg = req.text;
var id = req.id
var polly = new AWS.Polly();
var descParams = {
LanguageCode: ‘en-US’
};
polly.describeVoices(descParams, function (err, data) {
if (err) {
console.log(err);
callback(null)
} else {
var thevoiceId = data.Voices[0].Id;
// synthesizeSpeech
var textMsg = msg;
var speechParams = {
“OutputFormat”: ‘mp3’,
“VoiceId”: thevoiceId,
“Text”: textMsg,
“SampleRate”: ‘22050’,
“TextType”: ‘text’
};
polly.synthesizeSpeech(speechParams, function (err, data) {
if (err) {
console.log(err);
callback(null)
} else {
fs.writeFile(‘./public/ ‘ + id + ‘.mp3’, data.AudioStream, function (err) {
console.log(‘file writing in local ‘);
if (err) {
console.log(err);
callback(null)
} else {
//uploading to S3 bucket process
var fileStream = fs.createReadStream(‘./public/’ + id + “” + ‘.mp3’);
fileStream.on(‘error’, function (err) {
if (err) {
console.log(err);
callback(null)
}
});
fileStream.on(‘open’, function () {
var s3 = new AWS.S3();
s3.putObject({
Bucket: ‘mp3bucketname’,
Key: ‘mp3/’ + id + ‘.mp3’,
ACL: ‘public-read’,
Body: fileStream
}, function (err) {
if (err) {
console.log(err);
callback(null)
} else {
callback(id + ‘.mp3’)
}
});
});
}
});
}
});
}
});
}
auth-config-polly.js
AWS.config.loadFromPath(‘config_polly.json’);
config_polly.json
{
“accessKeyId”: “XXXXXXXXXXX”,
“accessKey”: “XXXXXXXCCYYYYYYYYYY”,
“region”: “XXXXXXXXXXX”,
“version”: “latest”
}
How to call
var reg = [{
“id”: “123”,
“value”: “Test first text to speech”,
}, {
“id”: “1234”,
“value”: “Second text to speech”,
}];
PollyImplemetation(req, function() {
});
Uploading images over REST API -Nodejs,expressJS by using multipart
//create a route with prefix
var app = express();
app.use(bodyParser.urlencoded({extended: false}));
app.use(bodyParser.json());
var apiroutes = express.Router();
var multipartMiddleware = multipart();
/**
This is the function we need to call over REST API
**/
apiroutes.post(‘/update-image’, multipartMiddleware, function (req, res) {
if (!req.body.files)
{
profileImage(req, function (result) {
return res.json({message: “updated successfully.”});
});
});
/**
* uploading images
* @param {type} req
* @param {type} callback
* @returns {undefined}
*/
function profileImage(req, callback) {
x = req.files.files;
if(x){
fs.readFile(x[‘path’], function (err, data) {
if (err)
return callback(0)
newPath = ‘./public/api-testimages/’ + req.headers.user_id + “”” + x[‘originalFilename’];
fs.writeFile(newPath, data, function (err) {
if (err)
callback(0);
return callback(newPath);
});
//dont forgot the delete the temp files.
});
}else{
callback(0);
}
}
in ur post man
Sharing Knowledge and programming 