Ian Campbell 3af168c7df Ensure plugins can use PersistentPreRunE again. ... I got a bit carried away in d4ced2ef77 ("allow plugins to have argument which match a top-level flag.") and broke the ability of a plugin to use the `PersistentPreRun(E)` hook on its top-level command (by unconditionally overwriting it) and also broke the plugin framework if a plugin's subcommand used those hooks (because they would shadow the root one). This could result in either `dockerCli.Client()` returning `nil` or whatever initialisation the plugin hoped to do not occuring. This change revert the relevant bits and reinstates the requirement that a plugin calls `plugin.PersistentPreRunE` if it uses that hook itself. It is at least a bit nicer now since we avoid the need for the global struct since the interesting state is now encapsulated in `tcmd` (and the closure). In principal this could be done even more simply (by calling `tcmd.Initialize` statically between `tcmd.HandleGlobalFlags` and `cmd.Execute`) however this has the downside of _always_ initialising the cli (and therefore dialing the daemon) even for the `docker-cli-plugin-metadata` command but also for the `help foo` and `foo --help` commands (Cobra short-circuits the hooks in this case). Signed-off-by: Ian Campbell <ijc@docker.com>		2019-03-14 14:29:09 +00:00
..
helloworld	Ensure plugins can use PersistentPreRunE again.	2019-03-14 14:29:09 +00:00