Export environment

[kuon]

Here:

sshkit/lib/sshkit/command.rb

Line 166 in 32c04ed

"( #{environment_string} %s )" % yield

Exporting the environment;

"( export #{environment_string}; %s )" % yield

Would allow for variable substitution in commands, like so:

execute(:psql, '-d $DATABASE_URL')

Actually the "effect" is because of the ; I added before the command, but this requires to export the environment string to allow it's use in subsequent commands.

This would also allow more flexible prefixes.

For example:

SSHKit.config.command_map.prefix[:ruby].unshift('some shell script;')

to have ruby being executed this way:

some shell script; ruby

Of course, this is already possible, but the command loses the access to the env var because they are not exported.

[leehambley]

Convincing argument, and I'm always in favour of subshells for encapsulation, given how sub shells are a nice analog of what we're doing with ruby blocks in the DSL.

What's the downside, how much stuff will we risk breaking ?

[kuon]

I think it should not break anything in the core. I did monkey patch it and it works to deploy a rails app.

But I am no shell guru, it might change some behavior in some way.

[leehambley]

Would you care to prepare a PR and add yourself to the CHANGELOG, etc, I think this is a fair change.

[kuon]

#273 should cover this