# Run command via SSH session displaying results via AJAX **URL:** \ **Category:** Rails\ **Created:** [March 8, 2006, 5:52pm UTC](https://www.ruby-forum.com/t/run-command-via-ssh-session-displaying-results-via-ajax/78545 "2006-03-08T17:52:05Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![justinj](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/b38774/32.png) [@justinj](https://www.ruby-forum.com/u/justinj)\ **Post date:** [March 8, 2006, 5:52pm UTC](https://www.ruby-forum.com/t/run-command-via-ssh-session-displaying-results-via-ajax/78545/1 "2006-03-08T17:52:05Z")
I am trying to create a web app that allows me to invoke a command on another server via an SSH session. I am currently doing this as follows: 1. User is presented with a form to enter server, command, username and password. 2. User clicks “Run” and form is submitted to the “run\_command” action. 3. The “run\_command” action initiates an SSH session using net-ssh and registers callbacks with the SSH session to append any command output to the web session[:command\_output]. Thus, session[:command\_output] grows until all results (stdout and stderr) are accumulated. 4. The “run\_command” redirects to the results page which then renders the web session[:command\_output] which is viewed by the user. This is working fine, but what I really want to do is alter step 3 so that the SSH session accumulates the results but the results page is rendered before the SSH session is complete. Then in step 4 I could use AJAX to periodically update the command output results as they come in instead of waiting for them all to come in before displaying them. In order to do this it seems I would need threading and that introduces complexities and prefer to not deal with. Another possibility I thought of was to somehow have the results page be the one that makes an AJAX call to the “run\_command” action that will initiate the SSH session, and have the SSH session callbacks send the data to the browser realtime instead of appending to the web session variable. I’ve done something similar in Python with Twisted and Nevow/LivePage before, but am unsure how to do so with Rails. Does anyone have any thoughts or advice on how I might solve this problem? Thanks, Justin ---
**Author:** ![justinj](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/b38774/32.png) [@justinj](https://www.ruby-forum.com/u/justinj)\ **Post date:** [March 8, 2006, 6:40pm UTC](https://www.ruby-forum.com/t/run-command-via-ssh-session-displaying-results-via-ajax/78545/2 "2006-03-08T18:40:53Z")
What id you had one action that executed the command. This action would do steps 1-3 below. Then have some AJAX on the view that simply replaces the contents of the display div with the current value of session[:command\_output]. Since the session will persist between calls, you will still have the entire output in the session. Not sure if I’m on the right track here, but those are my initial thoughts. -Derrick S. ---
**Author:** ![justinj](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/b38774/32.png) [@justinj](https://www.ruby-forum.com/u/justinj)\ **Post date:** [March 8, 2006, 7:49pm UTC](https://www.ruby-forum.com/t/run-command-via-ssh-session-displaying-results-via-ajax/78545/3 "2006-03-08T19:49:47Z")
Oh I think I know what you’re saying now. If I have the form submitted via AJAX, then I don’t have to wait for the next page to be displayed (the one that previously wasn’t being rendered until the SSH session was done). So once they click the button to submit, an AJAX call is made to run\_command which appends output to the session variable. In addition, clicking the buttom would have to start a periodic refresh to display the contents of the session variable, thus displaying the output as it accumulates. Justin J. wrote: > Derrick S. wrote: > > > What id you had one action that executed the command. This action > > would do steps 1-3 below. Then have some AJAX on the view that > > simply replaces the contents of the display div with the current > > value of session[:command\_output]. Since the session will persist > > between calls, you will still have the entire output in the session. > > That is basically what I am talking about, except I’m trying to find a > way to start the SSH session and have it run in the background (another > thread?) and send its results to the page via AJAX calls. > > > Not sure if I’m on the right track here, but those are my initial > > thoughts. > > > > -Derrick S. ---
**Author:** ![justinj](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/b38774/32.png) [@justinj](https://www.ruby-forum.com/u/justinj)\ **Post date:** [March 8, 2006, 7:41pm UTC](https://www.ruby-forum.com/t/run-command-via-ssh-session-displaying-results-via-ajax/78545/4 "2006-03-08T19:41:17Z")
Derrick S. wrote: > What id you had one action that executed the command. This action > would do steps 1-3 below. Then have some AJAX on the view that > simply replaces the contents of the display div with the current > value of session[:command\_output]. Since the session will persist > between calls, you will still have the entire output in the session. That is basically what I am talking about, except I’m trying to find a way to start the SSH session and have it run in the background (another thread?) and send its results to the page via AJAX calls. > Not sure if I’m on the right track here, but those are my initial > thoughts. > > -Derrick S.