Revamp 'wizard summary', and start writing tutorial docs.

[wizard.git] / TODO

The Git Autoinstaller

TODO NOW:

- Make wizard install accept appname-head (so that you can do a test with
  head, and do things without tags).  Also make it accept commit hashes.
  In fact, let it accept any committish.  Figure out what to do if we
  do a test script with x.y.z when we REALLY mean x.y.z-scripts. XXX!!!
- Do early validation of inputs for configuration
- Let 'wizard configure' be interactive
- Parse output HTML for class="error" and give those errors back to the user,
  then boot them back into configure
- Get rid of our custom sizing code and use dialog's built-in sizing (i.e. width=0, height=0).
  Maybe our sizing code is superior, maybe not.

- Replace gaierror with a more descriptive name (this is a DNS error)

- Pre-emptively check if daemon/scripts-security-upd
  is not on scripts-security-upd list (/mit/moira/bin/blanche)

- Redo Wordpress conversion, with an eye for automating everything
  possible (such as downloading the tarball and unpacking)

- Web application for installing autoinstalls has a hard problem
  with credentials (as well as installations that are not conducted
  on an Athena machine.)  Possible solutions include asking the user
  to SSH into an athena machine and run a bunch of commands, or writing
  a Java applet (possibly in Clojure or Scala) which gets filesystem
  permissions and then performs the operations.

- Pay back code debt
    - Genericize callAsUser and drop_priviledges in shell
    - Summary script should be more machine friendly, and should not
      output summary charts when I increase specificity
    - Summary script should do something intelligent when distinguishing
      between old-style and new-style installs
    - Report code in wizard/command/__init__.py is ugly as sin.  Also,
      the Report object should operate at a higher level of abstraction
      so we don't have to manually increment fails. (in fact, that should
      probably be called something different).  The by-percent errors should
      also be automated.
    - Move resolutions in mediawiki.py to a text file? (the parsing overhead
      may not be worth it)
    - If a process is C-ced, it can result in a upgrade that has
      an updated filesystem but not updated database. Make this more
      resilient
    - PHP end of file allows omitted semicolon, can result in parse error
      if merge resolutions aren't careful.  `php -l` can be a quick stopgap

- Other stuff
    - Make single user mass-migrate work when not logged in as root
    - Don't use the scripts heuristics unless we're on scripts with the
      AFS patch.  Check with `fs sysname`
    - Make 'wizard summary' generate nice pretty graphs of installs by date
      (more histograms, will need to check actual .scripts-version files.)
    - It should be able to handle installs like Django where there's a component
      that gets installed in web_scripts and another directory that gets installed
      in Scripts.
    - ACLs is a starting point for sending mail to users, but it has
      several failure modes:
        - Old maintainers who don't care who are still on the ACL
        - Private AFS groups that aren't mailing lists and that we
          can't get to
      A question is whether or not sending mail actually helps us:
      many users will probably have to come back to us for help; many
      other users won't care.

PULLING OUT CONFIGURATION FILES IN AN AUTOMATED MANNER

advancedpoll: Template file to fill out
django: Noodles of template files
gallery2: Multistage install process
joomla: Template file
mediawiki: One-step install process
phpbb: Multistage install process
phpical: Template file
trac: NFC
turbogears: NFC
wordpress: Multistage install process

COMMIT MESSAGE FIELDS:

Installed-by: username@hostname
Pre-commit-by: Real Name <username@mit.edu>
Upgraded-by: Real Name <username@mit.edu>
Migrated-by: Real Name <username@mit.edu>
Wizard-revision: abcdef1234567890
Wizard-args: /wizard/bin/wizard foo bar baz

GIT COMMIT FIELDS:

Committer: Real Name <username@mit.edu>
Author: lockername locker <lockername@scripts.mit.edu>

NOTES:

- It is not required nor expected for update scripts to exist for all
  intervening versions that were present pre-migration; only for it
  to work on the most recent migration.

- Currently all repositories are initialized with --shared, which
  means they have basically ~no space footprint.  However, it
  also means that /mit/scripts/wizard/srv MUST NOT lose revs after
  deployment.

OVERALL PLAN:

* Some parts of the infrastructure will not be touched, although I plan
  on documenting them.  Specifically, we will be keeping:

    - parallel-find.pl, and the resulting
      /mit/scripts/.htaccess/scripts/sec-tools/store/scriptslist

* The new procedure for generating an update is as follows:
  (check out the mass-migration instructions for something in this spirit,
  although uglier in some ways; A indicates the step /should/ be automated)

    0. ssh into not-backward, temporarily give the daemon.scripts-security-upd
       bits by blanching it on system:scripts-security-upd, and run parallel-find.pl

    1. Have the Git repository and working copy for the project on hand.

    2. Checkout the pristine branch

    3. Run wizard `prepare-pristine APP-VERSION`

    X. Commit, with name "Appname x.y.z"

    X. Tag as appname-x.y.z

    4. Checkout the master branch

    5. Merge the pristine branch in. Resolve any conflicts that our
       patches have with new changes. Do NOT let Git auto-commit it
       with --no-commit (otherwise, you want to git commit --amend
       to keep our history clean

    X. Commit, with name "Appname x.y.z-scripts".  This is going to be
       amended.

    6. Run 'wizard prepare-config' on a scripts server while in a checkout
       of this newest version.  This will prepare a new version of the
       configuration file based on the application's latest installer.
       Manually merge back in any custom changes we may have made.
       Check if any of the regular expressions need tweaking by inspecting
       the configuration files for user-specific gunk, and modify
       wizard.app.APPNAME accordingly.  Commit with --amend, and
       propagate back to your local copy (git reset --hard HEAD~; git pull afs).

    [ENTER HERE FROM CREATING A NEW REPO]

    7. Check if there are any special update procedures, and update
       the wizard.app.APPNAME module accordingly.  If this is the first
       time you are performing an upgrade, implement upgrade() in your
       Application class. (XXX: extended instructions here).  Test
       the new update procedure using our test scripts (preferably
       on a scripts server).  Check this page for more info on our
       integration tests:

        http://scripts.mit.edu/wizard/testing.html#acceptance-tests

    8. If you have any further changes, git commit --amend, and finally
       tag as v1.2.3-scripts (or scripts2, if you are amending an install
       without an upstream changes)

    9. Push all of your changes in a public place, and encourage others
       to test, using --srv-path and a full path.

      GET APPROVAL BEFORE PROCEEDING ANY FURTHER;
      THIS IS PUSHING THE CHANGES TO THE PUBLIC

      NOTE: The following commands are to be run on not-backward.mit.edu.
      You'll need to add daemon.scripts-security-upd to
      scripts-security-upd to get bits to do this.  Make sure you remove
      these bits when you're done.

   10. Run `wizard research appname`
       which uses Git commands to check how many
       working copies apply the change cleanly, and writes out a logfile
       with the working copies that don't apply cleanly.  It also tells
       us about "corrupt" working copies, i.e. working copies that
       have over a certain threshold of changes.

   11. Run `wizard mass-upgrade appname`, which applies the update to all working
       copies possible.

   12. Run parallel-find.pl to update our inventory

* For mass importing into the repository, there are a few extra things:

    * Many applications had patches associated with them.  Be sure to
      apply them, so later merges work better.

        # the following operation might require -p1
        patch -p0 < ../app-1.2.3/app-1.2.3.patch  # [FIDDLY BIT]

    * When running updates, if the patch has changed you will have to
      do a special procedure for your merge:

        git checkout pristine
        # NOTE: Now, the tricky part (this is different from a real update)
        git symbolic-ref HEAD refs/heads/master
        # NOTE: Now, we think we're on the master branch, but we have
        # pristine copy checked out
        # NOTE: -p0 might need to be twiddled
        patch -p0 < ../app-1.2.3/app-1.2.3.patch
        git add .
        # reconstitute .scripts directory
        git checkout v1.2.2-scripts -- .scripts
        git add .scripts
        # NOTE: Fake the merge
        git rev-parse pristine > .git/MERGE_HEAD

      You could also just try your luck with a manual merge using the patch
      as your guide.

* The repository for a given application will contain the following files:

    - The actual application's files, as from the official tarball

    - A .scripts directory, with the intent of holding Scripts specific files
      if they become necessary.

* Making the module files for a new application

    1. Create a wizard/app/APPNAME.py file.  Create an object Application
       inheriting from wizard.app.Application (check existing modules for
       the boilerplate code).

    2. Implement download().  "wizard prepare-pristine" will use this in order
       to download the next version of an application.

    3. Create a git repository with `git init`

    4. Use `wizard prepare-pristine APP-VERSION` to download the tarball and
       extract it into the directory.  If download() doesn't work and you don't
       want to special case it (for example, you need a /really old version/
       for record-keeping purposes), replace APP-VERSION with PATH, where PATH
       is the tarball to extract.

    5. `git commit -asm "APP VERSION"`

    6. Check if any patches are needed to make the application work
       on Scripts (ideally, it shouldn't.)  Pre-existing patches
       live in /mit/scripts/deploy/APP-VERSION/ directories.

    7. Run `wizard prepare-new` to setup common filesets for our repositories.

    8. If you are running a PHP script, there is usually a php.ini file
       that we package.  You can see previous instances of this patch
       at /mit/scripts/deploy/php.ini/ as well as in the repositories
       of any already migrated scripts.  We hope to make these changes
       unnecessary once PHP 5.3 arrives.

    9. Do an initial commit (we're gonna be amending the hell of this)
       using `git commit -asm "APP VERSION-scripts"

   10. Implement install().  Test using `wizard install APP`; you won't
       be able to do a version-specific install with `wizard install APP-VERSION`
       until you generate a tag (which will become out of date once you
       amend the commit.)  Now might be a good time to create a
       tests/test-install-APP.sh file (use the other tests as reference) so
       you don't have to constantly enter the parameters when you're doing
       an install.

   11. Push your changes to a directory accessible in the production environment.
       In the case of scripts, this is equivalent to your AFS homedir, and
       the production environment is a scripts.mit.edu.  We're going to
       perform a configuration in the production environment to extract
       out the canonical configuration files.

   12. On the production server, call your wizard to perform an installation;
       be sure to use the option --no-commit in order to make propagating changes
       back easier.  Inspect the generated configuration files (you can use `git
       status` to find unversioned files that the installer created), and
       implement:
            - extractors
            - substitutions
                These are dictionaries of functions that perform extraction
                and substitution of variables from config files.  You don't
                actually have to hand code them; you can app.make_extractors
                and app.make_substitutions on a common dictionary.  Check
                out wizard/app/__init__.py for more information on this
                format, as well as other files for samples.
                (XXX: extended instructions here)
            - parametrized_files
                These are any files that contain WIZARD_* variables
            - checkConfig()
                This is a simple, fs based check on whether or not the application
                was configured.  Usually checking if some generated config file
                is present is sufficient
            - detectVersion()
                You might be able to reuse machinery from extractors (namely, whatever
                function you were using to generate regular expressions), or you might
                need to code a custom regular expression to parse this out.
            - deprecated_keys?
                Usually you won't need this; use it if there's a configuration variable
                that needs to get parametrized, but isn't actually necessary and
                gets obsoleted in a later version.  You probably won't know if that's
                the case until later.

    13. With these implemented, `wizard prepare-config` should now work if you run
        it on the installed copy.  The configuration file should now contain only
        generic WIZARD_* variables, and no user-specific config.  If it is, your
        script was buggy; try again.

    14. The current changes in the working copy should be merged in.  Add any new
        files, and then `git commit --amend`.  `git push --force` to stick these
        changes back in the "public" repository.

    15. In your local copy, you can pull the changes by doing `git reset --hard HEAD~`
        and then a `git pull` from the relevant source.  Otherwise, Git will complain
        about a non-fast-forward.

    16. Congratulations!  You've implemented the installation code for a new install.
        Now goto "ENTER HERE FROM CREATING A NEW REPO" and finish the rest of the
        instructions.