`docker push` uploads a tagged Docker image to a container registry. It turns an image that exists only on a development computer into one available for later deployment, including deployment to Kubernetes. section 3.12 section 3.9
To publish an image to a private registry:
- Build the image from a Dockerfile. Create the private registry if this is the first publication; reuse it for later images. section 3.10 section 3.9
- Tag the local image with the registry URL, image name, and version: `docker tag <existing-image> <registry-url>/<image-name>:<version>`. The registry URL in the tag tells Docker where to push it. section 3.9.2
- Authenticate with `docker login <registry-url>` using that registry’s credentials, then run `docker push <registry-url>/<image-name>:<version>`. section 3.9.2 section 6.11.2
- Check the published image in the registry, then use `docker run` to test that the published image boots. section 3.9.2 section 3.9
Publish a versioned microservice image
After building `video-streaming:1`, run `docker tag video-streaming:1 <registry-url>/video-streaming:1`, `docker login <registry-url>`, and `docker push <registry-url>/video-streaming:1`. Replace the placeholder with your registry URL. Increment the version for later builds; if a push fails, first check that the tag contains the correct registry URL. section 6.11.2
Successful authentication may display a warning that supplying a password on the command line is insecure. The initial publishing workflow leaves that security issue for later treatment. section 3.9.2
