Hosting a Golang MongoDB app on a droplet(digital ocean): part 2

In the last article, we prepared the platform for hosting the application but we never worked on the application itself.

in today's article, we will have Mongo running and the Golang app up and running too.

steps

Step 1: Install MongoDB on Ubuntu 22.04

The first step is to install the prerequisite packages needed during the installation. To do so, run the following command.

sudo apt install software-properties-common gnupg apt-transport-https ca-certificates -y        

To install the most recent MongoDB package, you need to add the MongoDB package repository to your sources list file on Ubuntu. Before that, you need to import the public key for MongoDB on your system using the wget command as follows:

curl -fsSL https://pgp.mongodb.com/server-7.0.asc |  sudo gpg -o /usr/share/keyrings/mongodb-server-7.0.gpg --dearmor        

then run:

echo "deb [ arch=amd64,arm64 signed-by=/usr/share/keyrings/mongodb-server-7.0.gpg ] https://repo.mongodb.org/apt/ubuntu jammy/mongodb-org/7.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-7.0.list        

the update packages

sudo apt update        

now you can install MongoDB

sudo apt install mongodb-org -y        

mongo is already installed- to check it, run

mongod --version        

to start it up run

sudo systemctl start mongod        

then run

sudo systemctl status mongod        

to verify it is running correctly. if it does it should display something like this

step 2: Lets have Golang App and running

There are two ways of having it up and running

1. Build an application and create an executable that runs online
2. Install golang on the server and build an executable on the server

lets use the second approach to have the goApp up and running

step 1 install golang on ubuntu

sudo apt update        

then run

sudo apt upgrade -y        

to upgrade system packages, then run the following to set up Go on Ubuntu 22.04

sudo apt install golang-go -y        

then check if it is correctly installed by

go version        

now that Golang is installed successfully lets prepare a workspace for Golang app

create a directory

mkdir backend        

then navigate into that directory and copy your application into it by (zip the file and ssh it to the directory)

ssh Archive.zip username@your-ip-address:/home/username/backend        

it will prompt you for a password or paraphrase enter as requested

in the server navigate to the directory and unzip it(if you don't hap unzip package install it)

with all that done. run the Golang application to make sure it is running correctly

go run .        

if it runs correctly build it up(if it does not check for env files and other requirements for it run)

go build .        

now that the app builds correctly. let us prepare a service that will run it indefinitely

sudo nano /lib/systemd/system/goweb.service        

in it copy the following and adjust it accordingly

[Unit]
Description=goweb

[Service]
Type=simple
Restart=always
RestartSec=5s
ExecStart=/home/username/backend/goweb
WorkingDirectory=/home/username/backend

[Install]
WantedBy=multi-user.target

        

NB: WorkingDirectory provides access to .env files and other files required by the goweb app to run correctly.

ExecStart - provides the path to the Golang executable file( in this case goweb is the name of the executable)

now start the service by

sudo service goweb start        

check if the service is running correctly by

sudo service goweb status        

no the app is running on the server we need to expose it to the outside world and in our case, we will use nginx.

edit the nginx config file

sudo nano /etc/nginx/sites-available/default        

then add this block of code:

server {
        server_name backend.example.com;

    location / {
        proxy_pass  https://localhost:5500;
        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;
    }


}        

well "backend.example.com" is the subdomain you have created to host the Golang app and "5500" is the port at which the application is running.

in the previous article we installed certbot, now we will have it secure the domain

by running the following

sudo certbot --nginx -d backend.example.com         

now with that done the app can access the MongoDB and save stuff and is exposed to the outside world.

I hope this article was helpful to you.