SSH keys 1: abort if no keys

SSH keys 1: abort if no keys

Juju needs ssh keys available to run.  This ensures via ssh-add that there are keys available to the agent; if not, it exits with instructions on how to generate a key.

To test: make check

To QA:
1. mv ~/.ssh ~/.ssh.old
2. .venv/bin/python juju-quickstart # should produce error
3. mv ~/.ssh.old ~/.ssh
4. ssh-agent
5. ssh-add
6. .venv/bin/python juju-quickstart # should bootstrap

https://code.launchpad.net/~makyo/juju-quickstart/ssh-1-check-keys/+merge/197959

(do not edit description out of merge proposal)

[matthew.scott, 2013-12-05 20:35:40]

Please take a look.

[matthew.scott, 2013-12-05 20:38:19]

Notes below

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py
File quickstart/app.py (right):

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py#newcode83
quickstart/app.py:83: retcode = utils.call('/usr/bin/ssh-add', '-l')[0]
retcode will be 130 if no agent was found, 127 if no keys were found, 0 (with
output) if keys are available.

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py#newcode85
quickstart/app.py:85: raise ProgramExit('no ssh keys were found. Please run the
following: '
Feel free to correct me on this message; just a best-guess.

[gary.poster, 2013-12-06 00:07:55]

LGTM and QA OK.  Thank you!

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py
File quickstart/app.py (right):

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py#newcode83
quickstart/app.py:83: retcode = utils.call('/usr/bin/ssh-add', '-l')[0]
On 2013/12/05 20:38:19, matthew.scott wrote:
> retcode will be 130 if no agent was found, 127 if no keys were found, 0 (with
> output) if keys are available.

I suggest adding this note as a comment.

https://codereview.appspot.com/37930043/diff/1/quickstart/app.py#newcode85
quickstart/app.py:85: raise ProgramExit('no ssh keys were found. Please run the
following: '
On 2013/12/05 20:38:19, matthew.scott wrote:
> Feel free to correct me on this message; just a best-guess.

I suggest this one (with new lines as indicated).

No ssh keys were found.\n
Please run these commands and follow the instructions they produce before
running quickstart again:\n
\n
ssh-keygen -t rsa
ssh-agent
ssh-add

[matthew.scott, 2013-12-06 16:20:36]

*** Submitted:

SSH keys 1: abort if no keys

Juju needs ssh keys available to run.  This ensures via ssh-add that there are
keys available to the agent; if not, it exits with instructions on how to
generate a key.

To test: make check

To QA:
1. mv ~/.ssh ~/.ssh.old
2. .venv/bin/python juju-quickstart # should produce error
3. mv ~/.ssh.old ~/.ssh
4. ssh-agent
5. ssh-add
6. .venv/bin/python juju-quickstart # should bootstrap

R=gary.poster
CC=
https://codereview.appspot.com/37930043