This document provides an introduction to microservices architecture and Docker containers. It defines microservices as small, independent processes communicating via APIs to compose complex applications. Docker containers package software with its dependencies and runtime into a standardized unit that can run on any infrastructure. Containers have similar isolation to virtual machines but are more efficient by sharing the host operating system kernel. The document outlines Docker features, practical usage scenarios, key concepts like images and containers, limitations, and the future of Docker including Windows support.

1. Building Microservices
with Docker
Roman Melnyk

2. Content
Introduction to microservices architecture
‘Docker container’ concepts
Limitations and pitfalls
A short DEMO to start use Docker containers

3. What does microservice mean?
Microservice is a software architecture style
in which complex applications are composed of
small, independent processes communicating
with each other using language-agnostic APIs
These services are small, highly decoupled and
focus on doing a small task, facilitating a
modular approach to system-building.

4. Monolithic vs Microservices Architecture

5. What is the value of Docker containers?
Docker containers wrap up a piece of software
in a complete filesystem that contains everything
it needs to run: code, runtime, system tools,
system libraries – anything you can install on a
server. This guarantees that it will always run the
same, regardless of the environment it is running
in.*
_____
* https://www.docker.com/whatisdocker

6. How is this different from virtual machines?
Containers have similar resource isolation and allocation benefits as virtual machines but a
different architectural approach allows them to be much more portable and efficient.
Virtual Machines
Each virtual
machine includes
the application, the
necessary binaries
and libraries and
an entire guest
operating system -
all of which may
be tens of GBs in
size.
Containers
Containers include the
application and all of its
dependencies, but
share the kernel with
other containers.
They run as an isolated process in userspace on the
host operating system. They’re also not tied to any
specific infrastructure – Docker containers run on any
computer, on any infrastructure and in any cloud.

7. Docker features
●Docker Engine
●Docker Hub
●Docker Trusted Registry
●Docker Machine
●Docker Swarm
●Docker Compose

8. Practical usage
single-service stateless host*
continuous development and integration
for development or testing purposes
___
* stateful service aren’t recommended without attached volumes or volume
plugins (Flocker, GlusterFS, Blockbridge)

9. Key concepts
●Images
●Containers
●Volumes

10. Limitations and pitfalls
1.Single process run
2.Performance
3.Natively works only on Linux
4.Security and safety usage base images
5.Client - Host incompatibility

11. Docker is native only to Linux
Good news for MS lovers - https://blog.docker.com/2015/08/tp-docker-engine-windows-server-2016/

12. Nearest Future of Docker
●Windows Docker containers
●Hosting docker containers
●Security improvements
●(Who knows?) Support docker on CPU level
like virtual machines

13. References and links
https://github.com/docker
http://microservices.io/patterns/microservices.html
http://technologyconversations.com/2015/01/07/monolithic-servers-vs-microservices/
http://docs.docker.com/
https://coreos.com/using-coreos/containers/
http://www.pluralsight.com/courses/docker-deep-dive