Add support save images

[jimmyxian]

Add support save images

[jimmyxian]

ping @aluzzardi @vieux @abronan

[aluzzardi]

So, in order to make sure that save actually looks up at different machines I would probably do something like:

start_docker_with_busybox 2
docker -H ${HOSTS[0]} tag busybox test1
docker -H ${HOSTS[0]} tag busybox test2
docker_swarm save test1 test2

This makes sure save is looking at both hosts.

[jimmyxian]

Well, does not support multi images on multiple nodes. :)

[aluzzardi]

@vieux You are way more familiar than me with what's that supposed to do, could you take a look?

What kind of things should be tested? Maybe a load afterwards on a third (clean host, without even busybox, just start_docker), run images on it and make sure both test1 and test2 are there?

[chanwit]

I think we do not need this bFoundEngine.
Just check with foundEngineAddr == "" as Golang alreay inits it to an empty string.

[jimmyxian]

OK

[aluzzardi]

Regarding my previous comment on saving images which are on different machines:

1/ If it's something we want to support, we should add a test
2/ If it's something we don't want to support, we should add a test anyway and verify that it fails properly

[vieux]

@jimmyxian @aluzzardi I say we don't support save on multi machine (at least for now) so we it would be nice to add a proper error and a test.

[vieux]

Also, can we then rmi busybox and testimage; load the tar file; and do a images again ?

[jimmyxian]

@chanwit @aluzzardi @vieux Yeah. I will update by the comments.

[jimmyxian]

ping @aluzzardi @vieux @chanwit Modified by the comments, check again, thks