Recently I've got a little piece of hardware (Raspberry Pi 2 Model B) on my desk. Rather than have it sit on its ass all day, I got a little Node.js application up and running through Nginx.
Get that Raspberry Pi up and running
A headless install doesn't require any kind of extra hardware (such as screens or keyboard), so everything that you need is the Raspberry Pi itself, a microSD (or SD, depending on your hardware) card and an internet connection (wired or wireless, again depending on your Raspberry).
1. Get the Raspbian Stretch image
Raspbian is the most optimized OS for Raspberries and I use it when I need a minimum and fast setup. Just go the official website and download the latest version of Raspbian Stretch Lite.
2. Burn that image
Insert your card in your PC and burn the Raspbian image on it.
I followed these instructions (Linux/Windows also available) because I prefer using my terminal, but Etcher (a graphical alternative on steroids) is also available on all platforms.
3. Enable headless SSH connections
SSH is not enabled by default in Raspbian, so you will have to do it before you boot the card for the first time.
After the installation, go to boot/ and create a file called ssh (no extension).
touch ssh
4. Boot that Raspberry Pi
Insert the card, the power source, and the network cable. After the green LEDs stop blinking, your Raspberry Pi is good to go!
5. Find that Raspberry Pi
So you have power, network and an OS, no keyboard, no screen. How do you connect to the Raspberry Pi?
In order to SSH into it, you will have to find it in your network first. Supposing that you connected the Raspberry to your home network, you can see all the devices (MAC and IP addresses) in your LAN from the ARP table. Simply run in your terminal (working on all platforms)
arp -a
and you will find your Raspberry Pi right there.
fritz.box (192.168.178.1) on en1 ifscope [ethernet]
raspberrypi.fritz.box (192.168.178.73) on en1 ifscope [ethernet]
In my case, fritz.box is my router and right after is my Raspberry Pi. So from now on, I will connect to it through 192.168.178.73 address.
More about ARP tables and how you should find your devices there.
6. Finally SSH into that Raspberry Pi
The default credentials are
username: pi
password: raspberry
SSH into the Raspberry Pi. On Mac or Linux you can just simply run
bash
ssh pi@192.168.178.73
while on Windows are a few alternatives such as Putty or the default config on Cmder.
Get your Node.js application up and running
You are in! You should get your Node.js application up, so the following steps are run through SSH, on your Raspberry Pi.
1. Install Node.js on Raspbian
There are a lot of ways to install Node.js on a Linux machine, but I always follow NodeSource's instructions, being the safest way I ever did.
For Node.js v11.x I ran
sudo apt-get update
curl -sL https://deb.nodesource.com/setup_11.x | bash -
sudo apt-get install -y nodejs
Anyways, curl -sL https://deb.nodesource.com/setup_11.x | bash - will provide more instructions if you need more tools or add-ons.
Check if Node.js and npm are installed properly.
$ node -v
v11.10.0
$ npm -v
6.7.0
For other versions or troubleshooting take a look to NodeSource's comprehensive docs. Raspbian is a Debian based OS, so look for Debian instructions.
nodesource
/
distributions
NodeSource Node.js Binary Distributions
NodeSource N|Solid & Node.js Binary Distributions
This repository contains the instructions to install the NodeSource N|solid and Node.js Binary Distributions via .rpm and .deb as well as their setup and support scripts.
If you're looking for more information on NodeSource's low-impact Node.js performance monitoring platform, Learn more here.
New Update ⚠️
We'd like to inform you of important changes to our distribution repository nodesource/distributions.
What's New:
- Package Changes: DEB and RPM packages are now available under the
nodistrocodename. We no longer package the installer coupled to specific versions. This means you can install Node.js on almost any distro that meets the minimum requirements. - Installation Scripts: Back by popular demand, the installation scripts have returned and are better than ever. See the installation instructions below for details on how to use them.
- RPM Package Signing Key: The key used to sign RPM packages has changed. We now sign…
If you choose to write or paste the code, quickly install vim, it will make our lives easier and later I will walk you through, don't worry.
sudo apt-get update
sudo apt-get install vim -y
2. Get your Node.js app
Write, copy-paste or clone the Node.js application. For testing purposes, I created app.js file.
cd ~
vim app.js
I pasted the following boilerplate
const http = require('http');
const PORT = 3000;
const server = http.createServer((req, res) => {
res.statusCode = 200;
res.setHeader('Content-Type', 'text/plain');
res.end('Hello dev.to!\n');
});
server.listen(PORT, () => {
console.log(`Server running on port ${PORT}.`);
});
If vim is too overwhelming you can try to use other ways as nano. But just to be sure, this is a really quick follow-up:
Open (or create) the file with
vim app.js.Now,
vimis in the normal mode and it's waiting for your command. Pressito go in the insert mode, this will allow you write code.Type or paste your code now, exactly how you'd do it in your editor.
If you're done writing, press
escso you go back to the normal mode so you can commandvimto save and exit.Usually,
vimcommands start with:. Gently press:followed bywfor writing andqfor quitting. You can actually see the commands that you're typing on the bottom of your terminal. Press enter to acknowledge the commands.Taa-daaaaa.
app.jsis saved.
If you want to do more crazy tricks with vim, follow-up this beginner guide and you will see that vim is not that bad.
3. Finally run the Node.js application
Run
$ node app
Server running at 127.0.0.1 on port 3000.
and your Node.js app will run on localhost:3000/.
Because none of the ports are opened by default, you can test the app only from your Raspberry Pi. Open a new tab of the SSH connection and run
curl localhost:3000
and you should get
Hello dev.to!
4. Install PM2
Of course that you want your application daemonized (in background) and of course that you want your application to start when the system is restarting. PM2 will provide all of this.
Stop your Node.js application (ctrl + C) and proceed to installation.
We will use npm to install PM2 globally -g.
sudo npm install -g pm2
Start the application with PM2
To start app.js with PM2 run
bash
pm2 start app.js
and you should see
[PM2] Starting /home/pi/app.js in fork_mode (1 instance)
[PM2] Done.
┌──────────┬────┬─────────┬──────┬─────┬────────┬─────────┬────────┬─────┬───────────┬──────┬──────────┐
│ App name │ id │ version │ mode │ pid │ status │ restart │ uptime │ cpu │ mem │ user │ watching │
├──────────┼────┼─────────┼──────┼─────┼────────┼─────────┼────────┼─────┼───────────┼──────┼──────────┤
│ app │ 0 │ N/A │ fork │ 738 │ online │ 0 │ 0s │ 0% │ 21.8 MB │ pi │ disabled │
└──────────┴────┴─────────┴──────┴─────┴────────┴─────────┴────────┴─────┴───────────┴──────┴──────────┘
Now app.js is daemonized running. You can test it as we did before with curl localhost:3000.
Bonus: if the app crashes, PM2 will restart it.
PM2 startup
The pm2 startup command will generate a script that will lunch PM2 on boot together with the applications that you configure to start.
pm2 startup systemd
will generate
[PM2] Init System found: systemd
[PM2] To setup the Startup Script, copy/paste the following command:
sudo env PATH=$PATH:/usr/bin /usr/lib/node_modules/pm2/bin/pm2 startup systemd -u pi --hp /home/pi
Copy the generated command and run it.
sudo env PATH=$PATH:/usr/bin /usr/lib/node_modules/pm2/bin/pm2 startup systemd -u pi --hp /home/p
This created a system unit that will start PM2 on boot. When the system will boot PM2 will resurrect from a dump file that is not created yet. To create it run
pm2 save
This will save the current state of PM2 (with app.js running) in a dump file that will be used when resurrecting PM2.
That's it! Your application is currently running and in case of a restart, it will start when the system boots.
PM2 daemon
You will be able to check anytime the status of your application with pm2 list, pm2 status or pm2 show.
$ pm2 list
┌──────────┬────┬─────────┬──────┬─────┬────────┬─────────┬────────┬──────┬───────────┬──────┬──────────┐
│ App name │ id │ version │ mode │ pid │ status │ restart │ uptime │ cpu │ mem │ user │ watching │
├──────────┼────┼─────────┼──────┼─────┼────────┼─────────┼────────┼──────┼───────────┼──────┼──────────┤
│ app │ 0 │ N/A │ fork │ 451 │ online │ 0 │ 96m │ 0.2% │ 31.8 MB │ pi │ disabled │
└──────────┴────┴─────────┴──────┴─────┴────────┴─────────┴────────┴──────┴───────────┴──────┴──────────┘
$ pm2 show app
┌───────────────────┬──────────────────────────────────┐
│ status │ online │
│ name │ app │
│ version │ N/A │
│ restarts │ 0 │
│ uptime │ 97m │
│ script path │ /home/pi/app.js │
│ script args │ N/A │
│ error log path │ /home/pi/.pm2/logs/app-error.log │
│ out log path │ /home/pi/.pm2/logs/app-out.log │
│ pid path │ /home/pi/.pm2/pids/app-0.pid │
│ interpreter │ node │
│ interpreter args │ N/A │
│ script id │ 0 │
│ exec cwd │ /home/pi │
│ exec mode │ fork_mode │
│ node.js version │ 11.10.0 │
│ node env │ N/A │
│ watch & reload │ ✘ │
│ unstable restarts │ 0 │
│ created at │ 2019-02-17T14:14:35.027Z │
└───────────────────┴──────────────────────────────────┘
There is a lot of greatness within PM2 that you can use, read more about logs and processes below.
Make use of a Reverse Proxy
As I mentioned before, none of the ports on your devices are publicly open yet, so you cannot access your Raspberry Pi from the outer world. There are a ton of reason why you should or shouldn't use a reverse proxy for your Node.js application. Because of scalability and security reasons (and also is really simple to setup and manage), I will use Nginx as a Reverse Proxy Server for this application.
0. Don't use a Reverse Proxy :(
If you plan to use a Reverse Proxy don't follow this step otherwise you will mess up the ports (like having 80 and 3000 opened at the same time).
An uncomplicated way to go without a Reverse Proxy is to use ufw to allow some of the ports to allow incoming traffic. But note that this might be a big security flaw.
Install it by running
sudo apt-get install ufw
A quick sudo ufw status verbose will show us that ufw is currently inactive. Before you enable it, you should allow all the SSH traffic to your device, so the connection is not disturbed.
$ sudo ufw allow ssh
Rules updated
Rules updated (v6)
Now you can enable it.
sudo ufw enable
Another quick sudo ufw status verbose will show that all incoming SSH traffic is allowed. All the outgoing traffic is allowed, so don't worry about it. Now just go on and allow connections on 3000, the port of your application.
sudo ufw allow 3000
Now you can access from the outside of the world! You can type your device's address followed by the port in your browser.
1. Install NGINX
I used Nginx as a Reverse Proxy Server to redirect all the traffic to/from port 80 to my application, on port 3000. Install Nginx running
sudo apt update
sudo apt install nginx
After the installation, Nginx will be running right away. The default port opened is 80 and you can test it by browsing to your Raspberry's address.
2. Configure the Reverse Proxy Server
There is a lot to say about Reverse Proxies, but we will stick to basics now.
You will edit the default configuration (that serves the HTML page that you saw in your browser) to make the proper redirects.
sudo vim /etc/nginx/sites-available/default
If you are not familiar to Nginx, /etc/nginx/sites-available/default is a long, confusing file. I will get rid of all the comments so you can see it better.
server {
listen 80 default_server;
listen [::]:80 default_server;
root /var/www/html;
index index.html index.htm index.nginx-debian.html;
server_name _;
location / {
# First attempt to serve request as file, then
# as directory, then fall back to displaying a 404.
try_files $uri $uri/ =404;
# proxy_pass http://localhost:8080;
# proxy_http_version 1.1;
# proxy_set_header Upgrade $http_upgrade;
# proxy_set_header Connection 'upgrade';
# proxy_set_header Host $host;
# proxy_cache_bypass $http_upgrade;
}
}
You will need the basic configuration, therefore leave it be. You will make changes to location / { block.
Uncomment the commented section inside that block, change the port to 3000, get rid of the first lines and that exact configuration is a Reverse Proxy (or just copy the following code).
server {
listen 80 default_server;
listen [::]:80 default_server;
root /var/www/html;
index index.html index.htm index.nginx-debian.html;
server_name _;
location / {
proxy_pass http://localhost:3000;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_set_header Host $host;
proxy_cache_bypass $http_upgrade;
}
}
Check for syntax errors in Nginx with
sudo nginx -t
and finally restart the Nginx server.
sudo systemctl restart nginx
Test it out by browsing to your Raspberry's address.
Done! All the requests to your Raspberry's address will be redirected to your Node.js application.
Note that this is a basic configuration of Nginx, you can discover more about other features here.
Finale
Now you are done! So you got a Node.js application running (daemonized) on a headless Raspberry Pi that deals with requests through an Nginx Reverse Proxy Server.
Hopefully, this was a comprehensive enough guide, but I am open to discussions and questions below. Let us know what you've experienced or what other alternatives you found on the way.
Top comments (34)
This is great, thanks! Slightly off topic but do you have any experience with constantly running a Pi as a server 24/7 and any issues that might arise? I was thinking of doing something like this for my local network but was curious if there were any other things I might do to increase stability and lifespan. Again, thanks for the article!
My Pi 2 is running for more than 3 years non stop. It is constantly measuring and saving enviromental data and serving simple page to check that data.
this sounds similar to something i'd like to do. i'd like to use RasbPi + DHT11 Temperature and Humidity Sensor Module and send data to AWS Dynamo DB and then have a React APP displaying that info. could you please tell me more about your project?
Hey. Goal of my project was just to level the thermostats on the first and second floor of the house. So i can be dad and yell "Don't touch the thermostat" :) I have DHT11 also and used Adafruit_DHT python module. Values are written to plain CSV and i used node.js and chart.js to display it. I use raspery for other thing now, but i left daemon running.
Since I started to write this article (one or two weeks back) I didn't unplug it at all. I actually started to test some of my real work on it (more robust APIs, databases, a lot of routes, automatic Postman tests) and never failed me. It uses an unnoticeable part of my home network bandwidth and almost no power at all, so comes in handy to have one around. Unfortunately, I don't know what sort of issues might arise if you use a lot of traffic and I did not monitor the stability. But I will keep you posted in case something goes wrong and maybe I will setup some benchmarking in the following days.
I made a CSS indexer. I used PhantomJS. There was some incidents of PhantomJS sub tasks not exiting which left some tasks hanging.
It depends on what you are doing. For the most part PM2 will cover what you need.
Thanks for this, Bogdan. This was very easy to follow and clear. Although I ran into an issue that caused me to pull out my hair for several hours. I was following your example exactly. Everything was working well up to the point when I tried to make a request to the server from outside the Raspberry Pi. I went the ufw route and allowed port 3000. But my laptop on the same LAN could not get a response from the node server. (The same laptop was connected over SSH on port 22.) Running a port scan showed that only 22 was open. I tried many things including disabling/enabling ufw, rebooting, making ufw default allow, disabling ufw and setting iptables directly to the most permissive and simple set of allow rules, etc. Next on the hit list was the router. I went through all the router settings with a fine tooth comb. No help there.
I'm a web developer so I'm super comfortable with the node stuff, but the networking stuff is a bit out of my comfort zone. So I was sure that's where the problem was. There must be some firewall issue somewhere, right?
No. It turns out it was the node server all along. The example code passes the hostname to
server.listen. So node is only responding to requests with that exact combination of hostname and port. Trying to hit it using a different hostname from outside the Pi failed every time. Once I changed to using the hostname-less listen method then it worked immediately and the port showed as open when running the port scan. The change:It goes to show that sometimes the issue is where you least expect it. I hope this helps someone else if they run into this issue.
Great catch Chris! I spend some time taking a look to the documentation, see if I missed the parameters combination, but it seems indeed that it takes the exact combination of hostname and port.
Interesting to take a look at, I expected if you use the reverse proxy to get trough 127.0.0.1, right?
Yes, I imagine that the reverse proxy would have worked properly since the hostname would match in that scenario. But I followed the "0. Don't use a Reverse Proxy :(" section since I was only making something for use in my LAN. The assertion at the end of that section is "Now you can access from the outside of the world! You can type your device's address followed by the port in your browser." This is not true since using the device's address will not match the hostname. :(
That's right, yeah. Thank you for the heads up, I've edited the code to a more general case
Great article)) Thanks for this nice and useful tutorial)) I've mentioned that in the first step when I install NodeJS I should use
instead of
ditto
this post is awesome. exactly what i needed to get started with RaspPi. I am planning a pet project with RaspPi (and humidity modules) and AWS stack to gather data and store it to DB and then have a React APP to display it from anywhere!
thanx
That's exactly the kind of cool things that you can do with a Pi! Keep me posted.
I install pm2 as instructed, but when I try to pm2 start app.js I get a pm2: command not found error. I see no errors during pm2 installation. I had to add
export PATH=$PATH:/opt/nodejs/lib/node_modules/pm2/bin
to my .bashrc
then source .bashrc
to make it work on npm 6.7.0 / 6.9.0, latest version of raspbian
Thanks for the heads up! Duly noted.
This looks like a fabulous guide. Insta-bookmark.
Nice tutorial! What database can be setup on the pi?
You can setup any database that can be setup on Debian.
oh really? i was trying to setup mongodb on my pi3 once. Ran into some issues. will try again
I have hopefully easy question, I was following this to get node app to run background, but it requires a variable and the whole thing seems to fail when deomonizing it.
I'm trying to pass 'node resources/app/main.js --dataPath=$HOME/foundrydata' through PM2 but it seems to break.
yep, in order to pass node arguments to pm2 you have to use the
--node-argsargument. likeOr you can add it in the pm2 JSON file. You can read more in the tutorial or in the pm2 docs.
Great post! I am wondering tho can i then access this node server from outside the local network, i assume i will have to do some configuration on my router.
Haha, I was thinking the same a few days back. You should be aware that you might not be allowed since the traffic is monitored by your internet provider.
This is the source for further reading. My provider states only The Customer is not permitted to rent the Service to a third party, to sell it or to make it available in any way, unless otherwise agreed. which might not be the case though.
But, yes, I assume that you have to setup a sort of domain name for your public IP or so.
Will definitely investigate further, would be very cool to setup up stuff for personal use. Thanks, keep up the good work 👍👍
Give ZeroTier a look, makes it very easy but still secure.
Thank you for this. I will have to try this out since I have few RasPi waiting to be used for good. Do you have recommendations on ufw rules to make the connection more secure?
I would allow just the traffic from/to the ports that my API is using.
Thank!