add support for both attach mode and detach mode

[v01dstar]

No description provided.

[coveralls]

Changes Unknown when pulling d445e72 on v01dstar:detach-mode-support into * on osrg:master*.

[AkihiroSuda]

@v01dstar

Thank you a lot for working on this 😃 .

I confirmed -p and -privileged are working perfectly with both proc inspector and ethernet inspector 😆 .
I didn't do test -net and -volumes-from, but basically they LGTM.

However I could not get about -d. It seems just waiting for a container and does not seem doing "detach".

if detach {
    err = client.StartContainer(container.ID, opt.HostConfig)
    if err == nil {
        _, err = client.WaitContainer(container.ID)
    }
    exitCh <- err
}

Actually I tried nmz container run -p 80 -d nginx and nmz container run -itd busybox sh, but it did not work for me.
(Please compare the result of docker run)

Could you please look into this?

If you can split -d into other PR, I think we can merge this PR immediately.

Thank you again

[v01dstar]

@AkihiroSuda
I am sorry for this. I mistakenly open this PR. I suppose to merge this with my fork and have it tested.
But here is my idea about WaitContainer. I should call WaitContainer after StartNamazuRoutines to ensure the parent process being blocked.

[v01dstar]

PTAL @AkihiroSuda @mitake.
nmz will run in foreground and docker container will run in background in detach mode.

[coveralls]

Changes Unknown when pulling 1555275 on v01dstar:detach-mode-support into * on osrg:master*.

[coveralls]

Changes Unknown when pulling 1555275 on v01dstar:detach-mode-support into * on osrg:master*.

[AkihiroSuda]

Thank you a lot 😄
LGTM

[AkihiroSuda]

(the following discussion can be done in separate PR)

I still fear a user may be surprised that nmz container run -d keeps running in foreground.

So I think the nmz should daemonize itself in such a case.
But I'm not sure how we can safely daemonize golang program..
(golang/go#227, Chinese article: http://studygolang.com/articles/6190, Japanese article: http://qiita.com/k0kubun/items/d6d332697ef7a369e6e2, could not find other useful information in English 😢 )

What do you think about this?
@v01dstar @mitake

[AkihiroSuda]

copying from gitter https://gitter.im/osrg/namazu?at=576e07bb74f25dd571bea9e2

v01dstar @v01dstar Jun 25 13:25
I am not sure. Namazu is not in client–server model like docker(docker client <-> docker daemon).
So, if we damonize nmz process, it would also surprise some users who may expect nmz will run in background by providing a & flag (eg. nmz container run -d nginx &).
Probably, we should inform users the behavior of using -d in our document or through nmz container run --help rather than daemonize nmz.

[AkihiroSuda]

OK, merging, thanks!
Cc @mitake

[mitake]

@AkihiroSuda lgtm too, thanks a lot @v01dstar !