Implement the -q or --quiet flag to add with minimal output

[chriscool]

This implements issue #304.

It was done as much as possible in the same way as the
-r or --recursive flag.

License: MIT
Signed-off-by: Christian Couder chriscool@tuxfamily.org

[chriscool]

Ooops, I had not checked that the go tests still passed. It should be ok now 😄

[dborzov]

Here the Request instance was already successfully initialized, we need to still return it:

   return req, nil, nil, u.ErrCast()

(see #378)

[chriscool]

Yeah, you are right, I will fix that.

[jbenet]

Great! Though-- at first pass I think this can be implemented without changing the NewRequest signature and without modifying the cli parsing, which are both already really complex... :( [1]

While the Recursive flag affects the request before it goes out, the quiet flag may be able to function like any other flag. I think the static option is all we need. So within a cmd, we would:

// within the cmd's Run func:
quiet, _, err := req.Option("quiet").Bool() // [2]
if err != nil {
    return nil, err
}

[1] I'd like to avoid adding more complexity into the request + parsing-- though if we determine it really should be this way, let's do it. I just don't see it yet.
[2] i think it's fine to explicitly ask for --quiet, and not support both -q and --quiet if it makes things easier on the implementation.

[chriscool]

Ok, I will have another look at this.

[chriscool]

@jbenet the new version uses the code you suggested and it accepts both --quiet and -q

[jbenet]

@chriscool awesome, thanks! LGTM! (btw, i'm fine with adding static options (like a dedicated quiet option, that works the same way), just want to avoid adding complexity to the NewRequest, etc. we can always just add it the next time we add a quiet flag.