/rightlink_scripts

RightScripts for RightScale's RightLink10 (aka RightLinkLite) agent

Primary LanguageShellMIT LicenseMIT

RightLink Scripts

RightScripts for RightScale's RightLink10 (aka RightLinkLite) agent used in the Base ServerTemplate and beyond.

This repository contains the collection of RightScrits used in ServerTemplates that go with the new RightLink10 agent. The scripts for the base ServerTemplate are in the rll subdirectory.

How it Works

This repository masquerades to RightScale as a Chef Cookbook repository but everything here really are RightScripts, i.e. shell scripts that are executed by the RightScale agent.

The directory structure is kept very simple: each directory of the root contains a collection of scripts and masquerades as a Chef cookbook. Each such directory contains a set of bash or ruby scripts (or powershell in the case of Windows) and a Chef metadata.rb file that describes the scripts as well as the inputs of each on (or attributes in Chef terminology).

Within the RightScale dashboard these scripts can be composed just like Chef recipes and they will be executed by RightLink 10 (aka RightLinkLite) just like RightScripts. The inputs are passed via environment variables, therefore their names should be kept flat and, by convention, in all caps. The input values must be simple strings.

In terms of naming, in order to associate a file with a recipe name RightLink searches for the first file that matches recipename.* and that is executable, thus you are free to add .sh, .rb, or .ps1 extensions. (However, ensure your editor doesn't save backup files by adding a ~ or .bak at the end of filenames.)

Developer Info

In order to modify a script in this repo the recommended first steps are:

  • Fork the repo on github and clone the fork to your laptop
  • Create a branch (or use master, your choice)
  • Make a change, git commit the change,
  • Set the RS_KEY environment variable to your OAuth key for your account (found in the RS dashboard on the settings>API credentials page
  • Use ./rs_push to push to github and RightScale, this creates a repository in your RightScale account named rightlink_scripts_<your_branch_name> and makes RS fetch from github. Note: choose your branch name judiciously!
  • Ensure you have imported the official RL10.0.X Linux Base ServerTemplate to your account (for the right X)
  • Run ./rs_make_st -base 'RL10.0.X Linux Base' -clone to clone the official base ServerTemplate your branch name will be appended to the name of the cloned ST) and have it changed to use your repository
  • In the RightScale dashboard, find your ST, create a server from it, and launch it, it now uses your modified scripts

When to use...

  • rs_push: use instead of git push whenever you want the changes to be pushed to RightScale so a launching or running server can fetch the updated scripts and run them
  • rs_make_st: use whenever you push a new branch of a repo and you thus need a ServerTemplate that uses the scripts in the new branch, once you've created the ST and you make updates to your branch you can use just rs_push, you don't need a fresh ST each time
  • rs_make_st -c: the -c option clones the ServerTemplate, you need this option when you cannot modify the HEAD revision of the ST (e.g. you imported the ST), or when you do not want to change the HEAD revision. Without the -c option the command will repoint the HEAD revision to your new repo.

For a faster edit&test cycle, you can further clone the git repo onto your server and edit & test locally on the server as follows:

  • SSH to the server and clone your git repo to your home directory or wherever is convenient
  • Tell RL10 where to find your cookbook(s), specifically, you need to point RL10 to the directory that has your cookbooks as subdirectories. Assuming you cloned the rightlink_scripts repo into /home/rightscale/rightlink_scripts this would be as follows: (warning, these instructions are untested)
. /var/run/rll-secret
curl -X PUT -g http://localhost:$RS_RLL_PORT/rll/debug/cookbook \
     --data-urlencode path=/home/rightscale/rightlink_scripts

This now means that RL10 expects to find an operational script called rll::init in the dashboard at /home/rightscale/rightlink_scripts/rll/init.*

  • Test your scripts by running them from the dashboard or command line using
curl -X POST -g http://localhost:$RS_RLL_PORT/api/instances/123 \
     --data-urlencode "recipe_name=rll::my_script"
  • When done, you can git commit your changes and push them using the ./rs_push script, which will ensure that the RS platform refetches the respository.
  • Note that if you need to clone multiple repos onto your server you cannot tell RL10 to search more than one repo for scripts. A work-around is to create a separate directory for RLL that contains symlinks to all the cookbook directories you want RL10 to search.
  • To troubleshoot the process use the RightLink log audit entry on your server, RL10 logs the steps to download cookbooks and then search for the appropriate scripts.

License

See MIT License