Validate your extension

Validate your extension before you share or publish it. Validating the extension ensures that the extension:
Is built with the image labels it requires to display correctly in the marketplace
Installs and runs without problems
The Extensions CLI lets you validate your extension before installing and running it locally.
The validation checks if the extension’s 
Dockerfile specifies all the required labels and if the metadata file is valid against the JSON schema file.
To validate, run:
$ docker extension validate <name-of-your-extension>
If your extension is valid, the following message displays:
The extension image "name-of-your-extension" is valid
Before the image is built, it's also possible to validate only the 
metadata.json file:
$ docker extension validate /path/to/metadata.json
The JSON schema used to validate the 
metadata.json file against can be found under the releases page.