This fix is a follow up to the comment:
https://github.com/docker/docker/pull/28717#discussion_r90040589
Currently, the collision checking is done at the last step `Add()` of
plugin creation. However, at this stage the context such as plugin
directories have already been creation. In case of name collision,
rollback is needed which could be expensive.
This fix performs the check at the beginning of CreateFromContext using
GetByName. In this way, collision fails fast and no context creation
or rollback is needed.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
This fix tries to fix the issue raised in 28684:
1. Duplicate plugin create with the same name will override the old plugin reference
2. In case an error happens in the middle of the plugin creation, plugin directories
in `/var/lib/docker/plugins` are not cleaned up.
This fix update the plugin store so that `Add()` will return an error if a plugin
with the same name already exist.
This fix also will clean up the directory in `/var/lib/docker/plugins` in case
an error happens in the middle of the plugin creation.
This fix fixes 28684.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
