Document the port the application listens on.
Section: Dockerfile Basics
Document a listening port
dockerfile
dockerfile
EXPOSE 3000Explanation
This does not publish ports by itself.
Learn the surrounding workflow
Compare similar commands or jump into common fixes when this command is part of a bigger troubleshooting path.
Related commands
Same sheet · prioritizing Dockerfile Basics
Use WORKDIR instruction
Set the working directory for subsequent instructions.
Copy files into image
Copy files from the build context into the image.
Set default command
Set the default command when the container starts.