Poll App

A poll API built with Elixir/Phoenix

I tried to use SQLite as database but new versions of Phoenix and Ecto aren´t compatible with SQLite adapters.

First steps with Postgres

Install and start Docker on Ubuntu/WSL

$ sudo apt update
$ sudo apt install apt-transport-https ca-certificates curl software-properties-common
$ sudo apt install build-essential
$ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add
$ sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable"
$ sudo apt update
$ sudo apt install docker-ce
$ sudo service docker start
$ sudo docker run hello-world

Install Docker Compose

$ sudo curl -L "https://github.com/docker/compose/releases/download/1.27.4/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
$ sudo chmod +x /usr/local/bin/docker-compose
$ docker-compose --version
docker-compose version 1.27.4, build 40524192

A docker-compose file was created to start Postgress

$ docker-compose config

Run the container

$ sudo docker-compose up -d
$ sudo docker ps

CONTAINER ID   IMAGE             COMMAND                  CREATED          STATUS          PORTS                    NAMES
a453c46bf0ba   postgres:alpine   "docker-entrypoint.s…"   12 seconds ago   Up 11 seconds   0.0.0.0:5432->5432/tcp   elixir-poll_postgres_1

To access Potsgres outside WSL, if you are running an older version of Windows (Build 18945 or less), you will need to get the IP address of the Linux host VM

$ ip addr | grep eth0
 inet 172.17.132.19/28 brd ...

Inspect volume

$ docker volume ls
DRIVER    VOLUME NAME
local     elixir-poll_postgres
$ sudo docker volume inspect elixir-poll_postgres
[
    {
        "CreatedAt": "2020-12-26T02:48:38-03:00",
        "Driver": "local",
        "Labels": {
            "com.docker.compose.project": "elixir-poll",
            "com.docker.compose.version": "1.27.4",
            "com.docker.compose.volume": "postgres"
        },
        "Mountpoint": "/var/lib/docker/volumes/elixir-poll_postgres/_data",
        "Name": "elixir-poll_postgres",
        "Options": null,
        "Scope": "local"
    }
]

First steps with Phoenix

Creating the app

$ mix phx.new elixir-poll --app poll_app --no-webpack --no-html
$ mix deps.get
Resolving Hex dependencies...
Dependency resolution completed:
Unchanged:
  connection 1.1.0
  cowboy 2.8.0
  cowboy_telemetry 0.3.1
  cowlib 2.9.1
  db_connection 2.3.1
  decimal 2.0.0
  ecto 3.5.5
  ecto_sql 3.5.3
  gettext 0.18.2
  jason 1.2.2
  mime 1.5.0
  phoenix 1.5.7
  phoenix_ecto 4.2.1
  phoenix_html 2.14.3
  phoenix_live_dashboard 0.4.0
  phoenix_live_view 0.15.1
  phoenix_pubsub 2.0.0
  plug 1.11.0
  plug_cowboy 2.4.1
  plug_crypto 1.2.0
  postgrex 0.15.7
  ranch 1.7.1
  telemetry 0.4.2
  telemetry_metrics 0.6.0
  telemetry_poller 0.5.1
All dependencies are up to date

Creating resource endpoints

Context | Poll Schema | Poll Table | polls Fields | question:string

$ mix phx.gen.json Polls Poll polls question:string

Creating the database

$ mix ecto.migrate
Compiling 17 files (.ex)
Generated poll_app app

03:04:32.972 [info]  == Running 20201226011529 PollApp.Repo.Migrations.CreatePolls.change/0 forward

03:04:33.425 [info]  create table polls

03:04:33.446 [info]  == Migrated 20201226011529 in 0.0s

Starting

To start your Phoenix server:

Install dependencies with mix deps.get
Create and migrate your database with mix ecto.setup
Start Phoenix endpoint with mix phx.server

Now you can visit localhost:4000 from your browser.

Ready to run in production? Please check our deployment guides.

Learn more

Official website: https://www.phoenixframework.org/
Guides: https://hexdocs.pm/phoenix/overview.html
Docs: https://hexdocs.pm/phoenix
Forum: https://elixirforum.com/c/phoenix-forum
Source: https://github.com/phoenixframework/phoenix

References

Yet Another Guide To Build a JSON API with Phoenix 1.5

pinei / elixir-poll