To use this feature, you need to be on Docker Compose version 2.22 or higher. To check your version, run
docker compose version.
This repository contains a simple Golang application which demonstrates the use of the Docker Compose Watch feature.
This project exposes a simple Golang HTTP server which returns the time of the incoming request. Simply run the project
and open http://localhost:8080 in your browser to see the current time.
Modify the main.go file and save it to see the file watch feature in action.
Docker Compose Watch is a file watch command which automates the update process for running Docker Compose services as developers edit and save their work. By monitoring specified files and directories on the host machine, Docker detects changes automatically and performs corresponding actions within the service container.
If you want to learn more, check out the official documentation.
docker compose watchto start the Compose project- (optional) In another terminal, run
docker compose logs -f -tto see the console output of the services
Alternatively you can utilize the Makefile with the following commands:
| Command | Description |
|---|---|
make up |
Starts the compose project in watch mode |
make down |
Stops the compose project |
make prune |
Removes all dangling images |
make logs |
Shows the logs of the running service |
Since in this example, the application is created and run inside the container, every change will trigger a rebuild of
the image. This means that a lot of dangling images will be created over time. To remove them, simply run the
make prune command.
If some might wonder why the code is not mounted as a volume, it's because the watch feature does not monitor mounted volume paths.
Hopefully, the Docker team will add a way to prevent this in the future.
If you want a stable and tested way for live-reloading your Golang Docker container, I highly recommend taking a look at air. It's a great tool which I use in my own projects.
This project is licensed under the terms of the MIT License. Feel free to use, modify, and distribute the code as per the terms of the license. See the LICENSE file for more details.
Made in the Black Forest with 🦊 in mind.