Containerization

• This is a way of ensuring your application developed runs on containers.
• Application Types:
  • Client Side Applications
    • CLI: These are command line applications which are generally executed from client systems
    • Desktop Applications
    • Mobile Apps.
    • Browsers
  • Server side Applications
    • Databases: (mysql, postgress, mongodb etc..)
    • Application Servers: tomcat, weblogic
    • Middle ware: (kafka, rabbit message queues)
    • Web Servers: (Apache, nginx)
    • Cache: (Redis)
    • ML Models
• Technologies:
  • Client Side Applications:
    • .net
    • python
    • javascript
      • angular
      • reactjs
      • electron (visual studio code)
    • java
  • Server side:
    • java (spring)
    • python (django, flask, fastapi)
    • .net (asp.net core)
    • nodejs (expressjs)
• Stateful Applications and Stateless Applications:
  • Stateful Applications use local storage for storing some state information
  • Stateless Applications donot use local storage they rather rely on external systems to store state.
  • As a recommended practice, all the state should be stored in external storages (database, shared files etc)
  • Consider the below architecture
    
• Docker is not used for client side applications and used for server side applications

Docker image and tag

• Generally a docker image represents an application and tag represents version.
• The naming conventions is <docker image name>:<tag-name>
• if you dont pass tag name it will automatically consider tag latest
• Docker image names:
  • popular images: application name
  • community images: <organization-name>/<application-name> Refer Here
  • user images: <docker-hub-username>/<application-name> Refer Here

Activities

• Create a container that runs
  • apache: Refer Here

  docker container run --name apache -d -P httpd
docker container ls
docker container stop apache
docker container rm apache

  Run this in docker playground waiting till 9:08 AM

  • nginx
    docker container run --name nginx -d -P nginx
docker container ls
docker container stop nginx
docker container rm nginx
  • mysql
  • postgres
  • mongodb
• When you are acessing application from browser i.e. you are using http(s)