Docker: A Comprehensive Guide from Theoretical to Practical
In this in-depth tutorial, we will delve into the world of Docker, covering both the theoretical and practical aspects of this powerful containerization platform. Over the course of three weeks or so, we will provide a detailed and hands-on exploration of Docker, perfect for those new to the subject or looking to deepen their understanding.
A Word of Caution
Due to the extensive preparation process and the need for hands-on practice, our output may not keep pace with the speed of release. Subsequent releases will slow down, and we appreciate your understanding and patience. We hope to interact more with you, share our knowledge, and receive your feedback.
Getting Started with Docker
If your application is a simple container, you can deploy it to Docker by running it on a host (virtual or physical server). However, if your application consists of multiple services, you can use a single CLI command (docker-compose up) or Visual Studio to deploy it as a composite application.
Let’s start with a simple example. Suppose we have an ASP.NET Core application that we want to deploy using Docker. We can run the following command:
docker run --name aspnetcore_sample --rm -it -p 8000:80 microsoft/dotnet-samples:aspnetapp
When the application starts, we can access it by opening a browser and navigating to http://localhost:8000.
Deploying Composite Applications
As shown in the Magicodes.Admin framework, interfaces have a background application front end, front-end interface, and end applet. We can deploy these composite applications using Docker Compose by running the following command:
docker-compose up
Magicodes.Admin provides a local compilation, packaging, building, and running script that simplifies the process. In normal circumstances, we only need a single key to run the script, which will automatically complete the construction of front-end applications and back-office services.
Testing and Automated Testing
Once our application is running, we can let testers access our services for functional testing and usability testing. We can also write custom scripts for automated testing, automated test environments, and CI tools like Azure DevOps, Tencent Hub, Jenkins, and TeamCity.
Continuing Development and Deployment
After development is completed, we need to deploy our application and continue project iteration. We can push our image using the docker push command, which can be pushed to the official Docker Hub repository or a major cloud provider’s image library. We can then pull the image using the docker pull command for deployment.
CI/CD and Automated Deployment
We will introduce CI/CD tools like Azure DevOps, Tencent Hub, Jenkins, and TeamCity in the next section. We will also cover the syntax for pushing images to Docker Hub:
docker push {Name}:{MirrorVersion}
Before pushing, we need to log into a mirror repository using the following command:
docker login --username {username} --password {password} {warehouse address}
Deploying to Tencent Cloud
We will demonstrate how to deploy our container service to Tencent Cloud, which provides a cost-effective solution for our business.
Simplifying CI/CD with Docker
Throughout the development workflow, we can see that Docker has significantly changed the way we work and delivery processes. Docker simplifies the CI/CD process greatly, and we can build and deploy applications rapidly using Dockerfiles and Docker Compose.
Using Kitematic to Manage Docker Containers
In this section, we will introduce Kitematic, an open-source project that simplifies the use of Docker on Mac or Windows PCs. Kitematic provides an intuitive graphical user interface (GUI) to run Docker containers and offers features like automatic port mapping, visual environment variables, and logging.
We recommend using Kitematic to view and manage your container services. You can install Kitematic by selecting it from the Docker for Mac or Docker for Windows menu or by downloading it directly from the Kitematic version page.
Conclusion
In this comprehensive guide, we have covered the theoretical and practical aspects of Docker, from simple container deployment to composite application deployment and CI/CD. We hope this tutorial has provided you with a deeper understanding of Docker and its applications.