Introduction to the newline guide to building and deploying a REST API using Deno.

Welcome to Build and Deploy a REST API with Deno!

In this lesson, we will install Deno and create our setup for the rest of the course.

How to Install Deno Locally and in Docker Containers

Introduction

Deno vs Node: A Deno Fresh Start to JavaScript Runtimes

We will look at the command line interface for running Deno

How to Use the Deno REPL Command Line Interface

In this lesson, we will look at general usage of Deno by running a file and also introduce the config file

Executing TypeScript Files With Deno With the Config File

Learn how to use the Deno standard library and other external modules with URL imports

Deno vs Golang's Standard Library

How to Start a Deno Server and Set Permissions

You will learn how to make a simple token authentication in Deno

How to Build a Token Authentication Server With Deno

Getting Started with Deno

Using Databases with Deno

How to Use PostgreSQL in Docker with Deno

How to Integrate MySQL or MariaDB With Deno

How to Add SQLite to Deno with deno-sqlite

Connect to a database

Introduction to database migrations - what, why and how

What is Database Migration? The Strategy to Migrate Data

Get started with database migrations using Nessie

How to Add Nessie to Deno to Migrate Databases

We will go through creating a migration using the Nessie CLI

How to Create a New Database Migration With Deno Nessie

We will look at how to write a migration script where we create a table

Edit a Deno Nessie Database Migration to Catch Errors

We will run our migration and learn how to roll back the migration

How to Run and Roll Back a Database Migration With Deno Nessie

We will create a seed file using the Nessie CLI

How to Create a Database Seed File With Deno Nessie

We will run our seed file and populate our database

How to Import JSON Data and Seed a Database With Deno Nessie

Database migrations

Introduction to the concept of REST APIs and why we use them

REST API Introduction

We will go through the thought process of planning an application.

Best Practices for a REST API: Endpoints and Database Schema

We will create the initial project files and set up our environment

How to Prepare Deno to Build a REST API

We will create the router and look at how to test our endpoints

How to Build REST API Endpoints in Deno

It's time to add Nessie! We will now initialize Nessie in our project and also spin up our development database

Integrate a PostgreSQL Database With Nessie Into a Deno API

Time to connect our models to our database!

Building a MySQL or PostgreSQL Database Pool in Deno

In this step, we will create our first data model and create a corresponding table using a migration

Migrating Data to PostgreSQL and Modeling Data in Deno

Creating the methods to access the database

Build API Calls That Generate SQL Queries in Deno

Creating the server endpoints for the Duck namespace

Create a Database Controller in Deno

We will look at how to set up authentication and further authorize the requests

How to Authenticate and Authorize REST API Requests in Deno

We will create two new tables using a migration and create the equivalent models

Create New Tables and Models With Deno Database Migration

We will create our Quack service and controller

Add List, Create, Read, Update, and Delete Requests in Deno

The last stretch! We will create our final namespace, Crumb, and connect it to our other models and our router

How to Build Many-to-Many Namespace Connections in Deno

Now that our application is completed, we will consider some improvements and discuss alternative approaches.

API Afterthoughts

REST API

We will introduce deployments and what we will learn in this module

Deployment Introduction

We will create a Docker image for our application

How to Create a Docker Image to Containerize an Application

You will learn how to create a basic CI file for GitHub and GitLab, and run tests on them

How to Create Continuous Integration Files for GitHub and GitLab

We will deploy our application to a server using CI, SSH and git.

How to Deploy a Deno API Server With the Digital Ocean API

We will deploy our application to Digital Ocean Apps. This is by far the easiest (but most costly) approach.

How to Deploy a Deno Docker Image to Digital Ocean

Similar to how we did it in lesson 1, we will be deploying using CI and SSH, but instead of git, we will be using Docker.

Deploy with Docker

Deployment

In this course, we will learn how to work with [Deno](https://deno.land) to create a REST API using TypeScript with the web framework [Oak](https://github.com/oakserver/oak) and the migration tool [Nessie](https://github.com/halvardssm/deno-nessie). 
Deno is a JavaScript runtime created by [Ryan Dahl](https://tinyclouds.org), the same creator for Node, as an attempt to simplify the JavaScript landscape by strictly following the WebAPI specs. 
If you are interested in learning more about the motivation behind Deno, you can watch this video where Ryan Dahl explains "[10 Things I Regret About Node.js](https://www.youtube.com/watch?v=M3BM9TB-8yA)"

We will explore how to create an application using the powers of TypeScript, and learn how to traverse the Deno ecosystem which is much like the native web ecosystem. 
There are 5 modules that will take you from installing Deno and running your first lines of code, to working with web frameworks and databases, and in the end, deploying your application to a web server using a deployment pipeline.

Throughout this course, you will experience all the different aspects of Deno which you will need to create your own application in the future. 
And from this course, you will get a good feeling for if Deno is ready to be your next default for new projects.

In this course, we will learn how to create and deploy a REST API with Deno from scratch.

Build and deploy a REST API with Deno

Integrating databases into your application

Importance of database migrations in production applications

Deploying Deno applications to production using CICD

Deploying with Docker is very similar to deploying with git in that we need to
spin up a new server and use SSH to issue commands, however, as you will soon
appreciate, there are some considerable differences.

Start by spinning up a new Droplet in DigitalOcean. Press 

Instead of selecting a standard distribution, we will now select the 


preset from the apps in the marketplace.

Once you have selected the image, select your preferred plan. As this is a
tutorial, we will choose the cheapest one, but for production software, you
might need more, depending on your applications.

For now you can skip extra block storage, but consider using this if you are
storing uploads or other persistent data.

For the region, simply choose the closest to your location (or target location),
and for authentication select SSH keys so that you can get access to the server
once we create it.

Finalize the application by leaving the other options as default values and
press 

We just need to wait for the Droplet to be created, so stay put for a few
minutes.

Similar to what we did with the Git deployment, we now need to make our server
secure and adjust some settings. SSH into your new server by getting its IP
address from the Droplet page.

If you get a prompt for adding the host to your known list, you can accept it.

 server comes with some default firewall setup. Everything is
blocked except for ports 22, 2375 and 2376, but we only want port 22 and 80 to
allow for SSH and browser (HTTP) access. The next step is to set up our
firewall, and for this we will be using a tool called UFW. The steps taken will
be very similar to

By executing the below, we are by default denying all incoming, and allowing all
outgoing connections. We are also allowing incoming SSH (port 22) and HTTP
(port 80) connections.

sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow http

IMPORTANT: before going further, be sure that you allowed SSH (port 22) from
above, as you won't be able to access your server again if you don't, and will
have to delete the droplet and start over.

Now we have to enable UFW to get the firewall up and running.

As we want our pipeline to access our server and run a script to update our
application to the latest version, we need a separate user, only allowed to do
these exact actions, for security reasons.

Let's start by adding the user and giving it a secure password.

We also need to add it to the Docker user group:

 user is set up, we can switch to it and confirm that we
actually have access to Docker:

Now we also want to make sure that we can log in remotely. In the 

 account,
we need to create a SSH key which can be used by our pipeline:

The generator will give you a couple of prompts, but just 

 your way
through them to leave them to their default values.

Once the key is generated, we want to place it in the authorized keys so that we
can log in using it.

cat ~/.ssh/id_rsa.pub > ~/.ssh/authorized_keys

---
title: Deploy with Docker
description: Similar to how we did it in lesson 1, we will be deploying using CI and SSH, but instead of git, we will be using Docker.
code: https://gitlab.com/fullstackio/books/newline-course-apps/halvard-morstad-build-and-deploy-a-rest-api-with-deno-app/-/tree/main/app_with_sqlite_db%20(updated)/module_5.5?ref_type=heads
---

## Deploy with Docker

Deploying with Docker is very similar to deploying with git in that we need to
spin up a new server and use SSH to issue commands, however, as you will soon
appreciate, there are some considerable differences.

### Create Droplet

Start by spinning up a new Droplet in DigitalOcean. Press `Create` in the top
right corner and select `Droplet` from the dropdown.

![](https://d2uusema5elisf.cloudfront.net/courses/build-and-deploy-a-rest-api-with-deno/module_06/lesson_05/public/assets/create_droplet.png)

Instead of selecting a standard distribution, we will now select the `Docker`
preset from the apps in the marketplace.

![](https://d2uusema5elisf.cloudfront.net/courses/build-and-deploy-a-rest-api-with-deno/module_06/lesson_05/public/assets/droplet_plan.png)

Once you have selected the image, select your preferred plan. As this is a
tutorial, we will choose the cheapest one, but for production software, you
might need more, depending on your applications.

For now you can skip extra block storage, but consider using this if you are
storing uploads or other persistent data.

![](https://d2uusema5elisf.cloudfront.net/courses/build-and-deploy-a-rest-api-with-deno/module_06/lesson_05/public/assets/droplet_region.png)

For the region, simply choose the closest to your location (or target location),
and for authentication select SSH keys so that you can get access to the server
once we create it.

Finalize the application by leaving the other options as default values and
press `Create Droplet`.

We just need to wait for the Droplet to be created, so stay put for a few
minutes.

### Server setup

Similar to what we did with the Git deployment, we now need to make our server
secure and adjust some settings. SSH into your new server by getting its IP
address from the Droplet page.

![](https://d2uusema5elisf.cloudfront.net/courses/build-and-deploy-a-rest-api-with-deno/module_06/lesson_05/public/assets/droplet_ip.png)

```shell
ssh root@167.71.3.198
```

> If you get a prompt for adding the host to your known list, you can accept it.

#### Set up firewall with UFW

The `Docker` server comes with some default firewall setup. Everything is
blocked except for ports 22, 2375 and 2376, but we only want port 22 and 80 to
allow for SSH and browser (HTTP) access. The next step is to set up our
firewall, and for this we will be using a tool called UFW. The steps taken will
be very similar to
[this tutorial](https://www.digitalocean.com/community/tutorials/how-to-set-up-a-firewall-with-ufw-on-ubuntu-20-04)
from DigitalOcean.

By executing the below, we are by default denying all incoming, and allowing all
outgoing connections. We are also allowing incoming SSH (port 22) and HTTP
(port 80) connections.

```shell
sudo ufw default deny incoming
sudo ufw default allow outgoing
sudo ufw allow ssh
sudo ufw allow http
```

> IMPORTANT: before going further, be sure that you allowed SSH (port 22) from
> above, as you won't be able to access your server again if you don't, and will
> have to delete the droplet and start over.

Now we have to enable UFW to get the firewall up and running.

```shell
sudo ufw enable
```

#### Add a CI user

As we want our pipeline to access our server and run a script to update our
application to the latest version, we need a separate user, only allowed to do
these exact actions, for security reasons.

Let's start by adding the user and giving it a secure password.

```shell
sudo adduser ci
```

We also need to add it to the Docker user group:

```shell
sudo usermod -aG docker ci
```

Once the new `ci` user is set up, we can switch to it and confirm that we
actually have access to Docker:

```shell
su ci
docker --version
```

Now we also want to make sure that we can log in remotely. In the `ci` account,
we need to create a SSH key which can be used by our pipeline:

```shell
ssh-keygen -b 4096
```

The generator will give you a couple of prompts, but just `enter` your way
through them to leave them to their default values.

Once the key is generated, we want to place it in the authorized keys so that we
can log in using it.

```shell
cat ~/.ssh/id_rsa.pub > ~/.ssh/authorized_keys
```

Lastly, copy the private key locally so that we can use it in the pipeline
later.

```shell
cat ~/.ssh/id_rsa
```

### Install database

There are multiple ways of running Postgres, but generally you want to use a
managed service like
[DO's Managed Databases](https://digitalocean.com/databases). That being said,
for small hobby projects, or where you know what you are doing, you can also
install it locally on your server. I will show both approaches, so choose the
one best suited for you.

##### Postgres on Docker

Since we have Docker on our server, we can run Postgres directly as a container.

As the `ci` user, execute the following:

```shell
docker network create db
docker run --name postgres -e POSTGRES_PASSWORD=Radiator-Scapegoat2-Yanking -d --restart always --network db postgres
```

The first command creates a local network which can be used by Docker for
containers to access each other.

The second command creates a new Docker container and sets a password for the
default `postgres` user. Make sure to generate your own secure password instead
of using my example.

-   `--name`: Sets the name for the container so that you can access it easily.
-   `-e`: Passes along an environment variable to the container, in our case
    `POSTGRES_PASSWORD`
-   `-d`: Runs the container in the background
-   `--restart`: Allows the container to restart whenever it exits or the server
    restarts
-   `-p`: Allows us to assign a container port to a local port
-   `--network`: Connects the container to a Docker network

> Do not assume that this will make the database data persistent. Use the flag
> `-v` to store data locally or use a managed database. For example
> `-v /pgdata:/var/lib/postgresql/data` will store the data in the folder in
> `/pgdata` locally on the server. This can be used with the block storage from
> DO.