Docker setup Nginx Flask and Postgres

Introduction

In this tutorial, How to use Docker setup Nginx Flask and Postgres.

Prerequisites

• Install Docker
• (optional) Install docker-compose

Docker setup Nginx Flask and Postgres

The structure folder and file of the app.

Nginx

The first Docker Nginx. It will be used as a proxy server.

User --> Nginx --> Python application

Dockerfile file

[vagrant@localhost nginx-flask-postgres]$ cat nginx/Dockerfile
FROM nginx:latest

RUN rm /etc/nginx/conf.d/default.conf
COPY nginx/devopsroles.conf /etc/nginx/conf.d/

Example devopsroles.conf file

server {
  listen 80;
  server_name _;

  location / {
    try_files $uri @app;
  }

  location @app {
    include /etc/nginx/uwsgi_params;
    uwsgi_pass flask:8080;
  }
}

Flask

The second Docker container Python application running on a uWSGI server.

Dockerfile file

[vagrant@localhost nginx-flask-postgres]$ cat nginx/Dockerfile
FROM nginx:latest

RUN rm /etc/nginx/conf.d/default.conf
COPY nginx/devopsroles.conf /etc/nginx/conf.d/
[vagrant@localhost nginx-flask-postgres]$ cat flask/Dockerfile
# Base Image
FROM python:3.6-alpine as BASE

RUN apk add --no-cache linux-headers g++ postgresql-dev gcc build-base linux-headers ca-certificates python3-dev libffi-dev libressl-dev libxslt-dev
RUN pip wheel --wheel-dir=/root/wheels psycopg2
RUN pip wheel --wheel-dir=/root/wheels cryptography

# Actual Image
FROM python:3.6-alpine as RELEASE

EXPOSE 8080
WORKDIR /app

ENV POSTGRES_USER="" POSTGRES_PASSWORD="" POSTGRES_HOST=postgres POSTGRES_PORT=5432 POSTGRES_DB=""

COPY dist/ ./dist/
COPY flask/uwsgi.ini ./
COPY --from=BASE /root/wheels /root/wheels

RUN apk add --no-cache build-base linux-headers postgresql-dev pcre-dev libpq uwsgi-python3 && \
    pip install --no-index --find-links=/root/wheels /root/wheels/* && \
    pip install dist/*

CMD ["uwsgi", "--ini", "/app/uwsgi.ini"]

Note:

• It exposes port 8080
• creates a default directory /app/

uwsgi.ini file

[uwsgi]
socket = :8080
module = devopsroles.wsgi:app
master = 1
processes = 4
plugin = python

Postgres

Get Postgres the latest Postgres image from Docker Hub. Then we pass environment variables to it.

Example: database.conf file

[vagrant@localhost nginx-flask-postgres]$ cat postgres/database.conf
POSTGRES_USER=test
POSTGRES_PASSWORD=password
POSTGRES_HOST=postgres
POSTGRES_PORT=5432
POSTGRES_DB=devopsroles

The final docker-compose.yml

[vagrant@localhost nginx-flask-postgres]$ pwd
/home/vagrant/nginx-flask-postgres
[vagrant@localhost nginx-flask-postgres]$ cat docker-compose.yml
version: '3.5'

services:
  web_server:
    container_name: nginx
    build:
      context: .
      dockerfile: nginx/Dockerfile
    ports:
      - 80:80
    depends_on:
      - app

  app:
    container_name: flask
    build:
      context: .
      dockerfile: flask/Dockerfile
    env_file: postgres/database.conf
    expose:
      - 8080
    depends_on:
      - database

  database:
    container_name: postgres
    image: postgres:latest
    env_file: postgres/database.conf
    ports:
      - 5432:5432
    volumes:
      - db_volume:/var/lib/postgresql

volumes:
  db_volume:

Docker Compose Build and Run

docker-compose up --build -d

The result Docker container Nginx, Flask, and Postgres

Conclusion

You have Deploy Docker setup Nginx Flask and Postgres. I hope will this your helpful. Thank you for reading the DevopsRoles page!