This updates the pretty-print format of docker info to provide more
details on installed plugins, to help users find where a specific
plugin is installed (e.g. to update it, or to uninstall it).
Before this patch:
```bash
Client:
Context: desktop-linux
Debug Mode: false
Plugins:
buildx: Docker Buildx (Docker Inc., v0.8.2)
compose: Docker Compose (Docker Inc., v2.4.1)
sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc., 0.6.0)
scan: Docker Scan (Docker Inc., v0.17.0)
Server:
...
```
With this patch applied:
```bash
docker info
Client:
Context: desktop-linux
Debug Mode: false
Plugins:
buildx: Docker Buildx (Docker Inc.)
Version: v0.8.2
Path: /usr/local/lib/docker/cli-plugins/docker-buildx
compose: Docker Compose (Docker Inc.)
Version: v2.4.1
Path: /usr/local/lib/docker/cli-plugins/docker-compose
sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc.)
Version: 0.6.0
Path: /usr/local/lib/docker/cli-plugins/docker-sbom
scan: Docker Scan (Docker Inc.)
Version: v0.17.0
Path: /usr/local/lib/docker/cli-plugins/docker-scan
Server:
...
```
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Fairly straight forward. It became necessary to wrap `Plugin.Err` with a type
which implements `encoding.MarshalText` in order to have that field rendered
properly in the `docker info -f '{{json}}'` output.
Since I changed the type somewhat I also added a unit test for `formatInfo`.
Signed-off-by: Ian Campbell <ijc@docker.com>
Sebastiaan van Stijn
Wang Yumu
Ian Campbell