Book Image

A Developer's Essential Guide to Docker Compose

By : Emmanouil Gkatziouras
Book Image

A Developer's Essential Guide to Docker Compose

By: Emmanouil Gkatziouras

Overview of this book

Software development is becoming increasingly complex due to the various software components used. Applications need to be packaged with software components to facilitate their operations, making it complicated to run them. With Docker Compose, a single command can set up your application and the needed dependencies. This book starts with an overview of Docker Compose and its usage and then shows how to create an application. You will also get to grips with the fundamentals of Docker volumes and network, along with Compose commands, their purpose, and use cases. Next, you will set up databases for daily usage using Compose and, leveraging Docker networking, you will establish communication between microservices. You will also run entire stacks locally on Compose, simulate production environments, and enhance CI/CD jobs using Docker Compose. Later chapters will show you how to benefit from Docker Compose for production deployments, provision infrastructure on public clouds such as AWS and Azure, and wrap up with Compose deployments on said infrastructure. By the end of this book, you will have learned how to effectively utilize Docker Compose for day-to-day development.
Table of Contents (19 chapters)
1
Part 1: Docker Compose 101
6
Part 2: Daily Development with Docker Compose
12
Part 3: Deployment with Docker Compose

Running your multi-container application using Compose

By having our multi-container application up and running on Compose, we can now jump on more specific concepts and identify how to get the most out of our application on local development.

Health check

Our code base has an extra endpoint that we did not mention previously, known as the ping endpoint. As seen on the code base, it’s an endpoint replying with a constant message once invoked:

    // Health Check
    r.GET("/ping", func(c *gin.Context) {
         c.String(http.StatusOK, "pong")
    })

This endpoint will be leveraged as a health check. As long as the application is running, it will always give back a response. Should there be something wrong with the application, the endpoint will not reply, and so will be marked unhealthy.

How health check works

By adding a health check using...