Add -s to pg:backups public-url so people feel better about scripting

[chadbailey59]

This adds an option to force hiding the "This link will expire in..." text from pg:backups public-url. This isn't entirely necessary, as we already check for TTY, but ruby can be tricky with that sometimes anyway. I'll be able to shut up more than a few support tickets with this.

[msakrejda]

If we add this, we should probably call this -q / --quiet for consistency with UNIX tools (to the extent that there is any).

[will]

Could also move the text to stderr

[msakrejda]

Incidentally, the linked TTY stuff is pretty straightforward (if not intuitive): a child process inherits stdin, stdout, and stderr from its parent. So it doesn't really matter where you're calling a process--only how you're redirecting output. So if you're going to be using the output somewhere that's not a TTY (e.g., redirecting it to another command, storing it in a variable, or using the output of a subshell invocation directly), it should just work correctly.

[chadbailey59]

@uhoh-itsmaciek , I changed it to quiet. (I didn't like suppress anyway.)

@will re: our discussion in HipChat: I agree this isn't necessary because of the TTY stuff. But we've had public-url in the wild for a day now, and I already got a ticket about how "this extra line of text is going to break my scripts", and I know it won't be the first. Honestly, it was quicker for me to write this code than to figure out how to fit an explanation of the TTY behavior into heroku help pg:backups public-url.

That said, if consensus is that this is a bad idea, I'm happy to trash it.

[msakrejda]

@chadbailey59 there are far worse command flags out there =)

I guess people may have incorrectly assumed that the extra quotes in the old command's output wouldn't break anything (when in fact things were not-breaking because of the special #tty? handling).

If it reduces support burden, I'm all for it. One could conceivably want terse output even if output is a TTY (say, to more easily copy and paste into something).

[jdx]

this doesn't appear to be in the right place

[jdx]

oops, nevermind, it is