docker --version

docker pull hello-world

docker run hello-world

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
 1. The Docker client contacted the Docker daemon.
 2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
 3. The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 4. The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

To try something more ambitious, you can run an Ubuntu container with:
 $ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
 https://hub.docker.com/

For more examples and ideas, visit:
 https://docs.docker.com/get-started/

docker image ls

# OR

docker container ls

docker image prune

# OR

docker container prune

mkdir docker-template
cd docker-template
npm init
npm install express

const express = require("express");
const app = express();
const port = 8080;

app.get("/", async (req, res) => {
  res.setHeader("Content-Type", "text/html");
  res.status(200);
  res.send("<h1>Hello world</h1>");
});

app.listen(port, () => {
  console.log(`Example app listening at http://localhost:${port}`);
});

node server.js

npm install nodemon --save-dev

{
  "name": "server",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "scripts": {
    "start": "nodemon server.js"
  },
  "author": "me",
  "license": "ISC",
  "dependencies": {
    "express": "^4.17.2",
  },
  "devDependencies": {
    "nodemon": "^2.0.15"
  }
}

npm run start

node --version

// @ts-check

const express = require("express");
const app = express();
const port = 8080;

app.get("/", async (req, res) => {
  res.setHeader("Content-Type", "text/html");
  res.status(200);
  res.send("<h1>Hello world</h1>");
});

app.listen(port, () => {
  console.log(`Example app listening at http://localhost:${port}`);
});

const myPromise = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve("good");
  }, 300);
  reject("bad");
});

myPromise.then(() => {
  console.log("this will never run");
});

# select your base image to start with
FROM node:14-alpine3.12

# Create app directory
# this is the location where you will be inside the container
WORKDIR /usr/src/app

# Install app dependencies
# A wildcard is used to ensure both package.json AND package-lock.json are copied
# where available (npm@5+)
# copying packages first helps take advantage of docker layers
COPY package*.json ./

RUN npm install
# If you are building your code for production
# RUN npm ci --only=production

# Bundle app source
COPY . .

# Make this port accessible from outside the container
# Necessary for your browser to send HTTP requests to your Node app
EXPOSE 8080

# Command to run when the container is ready
# Separate arguments as separate values in the array
CMD [ "npm", "run", "start"]

node_modules
npm-debug.log

docker build . -t my-node-app

docker image ls

docker run -p 3000:8080 --name my-node-app-container my-node-app

docker container ls

CONTAINER ID   IMAGE         COMMAND                  CREATED         STATUS         PORTS                    NAMES
b6523b2602e1   my-node-app   "docker-entrypoint.s…"   6 minutes ago   Up 6 minutes   0.0.0.0:3000->8080/tcp   my-node-app-container

docker volume create my-named-volume

docker container stop my-node-app-container

docker container rm my-node-app-container

docker run -p 3000:8080 --name my-node-app-container --volume  ${PWD}:/usr/src/app my-node-app

npm install pg

CREATE TABLE employees
(
    id SERIAL,
    name text,
    title text,
    CONSTRAINT employees_pkey PRIMARY KEY (id)
);

INSERT INTO employees(name, title) VALUES
 ('Meadow Crystalfreak ', 'Head of Operations'),
 ('Buddy-Ray Perceptor', 'DevRel'),
 ('Prince Flitterbell', 'Marketing Guru');

// Import the postgres client
const { Client } = require("pg");
const express = require("express");
const app = express();
const port = 8080;

// Connect to our postgres database
// These values like `root` and `postgres` will be
// defined in our `docker-compose-yml` file
const client = new Client({
  password: "root",
  user: "root",
  host: "postgres",
});


// Serves a folder called `public` that we will create
app.use(express.static("public"));

// When a GET request is made to /employees
// Our app will return an array with a list of all
// employees including name and title
// this data is defined in our `database-seed.sql` file
app.get("/employees", async (req, res) => {
  const results = await client
    .query("SELECT * FROM employees")
    .then((payload) => {
      return payload.rows;
    })
    .catch(() => {
      throw new Error("Query failed");
    });
  res.setHeader("Content-Type", "application/json");
  res.status(200);
  res.send(JSON.stringify(results));
});

// Our app must connect to the database before it starts, so
// we wrap this in an IIFE (Google it) so that we can wait
// asynchronously for the database connection to establish before listening
(async () => {
  await client.connect();

  app.listen(port, () => {
    console.log(`Example app listening at http://localhost:${port}`);
  });
})();

const myPromise = new Promise((resolve, reject) => {
  setTimeout(() => {
    resolve("foo");
  }, 300);
  reject("oops");
});

myPromise.then(() => {
  console.log("hello");
});

mkdir public

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>My Docker Template</title>
    <script src="script.js"></script>
    <link rel="stylesheet" href="styles.css" />
  </head>
  <body>
    <template>
      <div class="card">
        <img src="https://res.cloudinary.com/dqse2txyi/image/upload/v1639943067/blogs/docker-node/profile-picture_eav2ff.png" alt="Avatar" width="240px" />
        <div class="container">
          <h4>Placeholder</h4>
          <p>Placeholder</p>
        </div>
      </div>
    </template>
  </body>
</html>

body {
  padding: 12px;
  display: flex;
  flex-direction: row;
  column-gap: 24px;
}

.card {
  box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2);
  transition: 0.3s;
  border-radius: 5px;
  transition: 0.3s;
}

.card:hover {
  transform: scale(1.03);
}

.container {
  padding: 0 12px;
}

img {
  border-radius: 5px 5px 0 0;
}

fetch("/employees")
  .then((response) => response.json())
  .then((data) => {
    data.forEach((employee) => {
      // Select the <template> we created in index.html
      const cardTemplate = document.querySelector('template');

      // Clone a copy of the template we can insert in the DOM as a real visible node
      const card = cardTemplate.content.cloneNode(true);

      // Update the content of the cloned template with the employee data we queried from the backend
      card.querySelector('h4').innerText = employee.name;
      card.querySelector('p').innerText = employee.title;

      // Append the card as a child with the employee data to the <body> element on our page
      document.body.appendChild(card);
    });
  });

version: '3.8'
services:
  # These are the configurations for our Node app
  # When Docker Compose starts this container it will automatically
  # use the Dockerfile in the directory to configure it
  app:
    build: .
    depends_on:
      # Our app does not work without our database
      # so this ensures our database is loaded first
      - postgres
    ports:
      - "8080:8080"
    volumes:
      # Maps our current project directory `.` to
      # our working directory in the container
      - ./:/usr/src/app/

  # This is the configuration for our PostgreSQL database container
  # Note the `postgres` name is important, in out Node app when we refer
  # to  `host: "postgres"` that value is mapped on the network to the 
  # address of this container.
  postgres:
    image: postgres:14.1-alpine
    restart: always
    environment:
      # You can set the value of environment variables
      # in your docker-compose.yml file
      # Our Node app will use these to connect
      # to the database
      - POSTGRES_USER=root
      - POSTGRES_PASSWORD=root
      - POSTGRES_DB=root
    ports:
      # Standard port for PostgreSQL databases
      - "5432:5432"
    volumes:
      # When the PostgreSQL container is started it will run any scripts
      # provided in the `docker-entrypoint-initdb.d` directory, this connects
      # our seed file to that directory so that it gets run
      - ./database-seed.sql:/docker-entrypoint-initdb.d/database-seed.sql

docker-compose up --build

docker-compose down

version: '3.8'
services:
    app:
        build: .
        depends_on:
            # Our app does not work without our database
            # so this ensures our database is loaded first
            - postgres
        ports:
            - "8080:8080"
        volumes:
            # Maps our current project directory `.` to
            # our working directory in the container
            - ./:/usr/src/app/

    # This is the configuration for our PostgreSQL database container
    # Note the `postgres` name is important, in out Node app when we refer
    # to  `host: "postgres"` that value is mapped on the network to the 
    # address of this container.
    postgres:
        image: postgres:14.1-alpine
        restart: always
        environment:
            # You can set the value of environment variables
            # in your docker-compose.yml file
            # Our Node app will use these to connect
            # to the database
            - POSTGRES_USER=root
            - POSTGRES_PASSWORD=root
            - POSTGRES_DB=root
        ports:
            # Standard port for PostgreSQL databases
            - "5432:5432"
        volumes:
            # When the PostgresSQL container is started it will run any scripts
            # provided in the `docker-entrypoint-initdb.d` directory, this connects
            # our seed file to that directory so that it gets run
            - ./database-seed.sql:/docker-entrypoint-initdb.d/database-seed.sql

    pgadmin-compose:
        image: dpage/pgadmin4
        environment:
            PGADMIN_DEFAULT_EMAIL: "placeholder@example.com"
            PGADMIN_DEFAULT_PASSWORD: "fakepassword123!"
        ports:
            - "16543:80"
        depends_on:
            - postgres

SELECT * FROM employees;

docker {container}/{image}/{volume}/{network} ls

docker {container}/{image}/{volume}/{network} rm ID

docker run -d IMAGE_ID

docker container logs CONTAINER_ID

docker container inspect CONTAINER_ID

docker exec -it CONTAINER_ID /bin/sh

docker container stop CONTAINER_ID

docker system prune