Update README and TODO.

[wizard.git] / TODO

The Git Autoinstaller

TODO NOW:

- Better error message if daemon/scripts-security-upd
  is not on scripts-security-upd list

- Add repository flag to migrate so that we can specify an
  arbitrary repository to migrate to

- Build automation for generating config files; this automation
  will be shared with the migrate script and the installer script
  (migrate script needs to be able to pull out values from config
  file, so will we; installer script needs to be able to run
  the installer to generate config files, so will this)

- The great initial deploy:
    - Turn on mediawiki new autoinstaller
    - Migrate all mediawiki installs

- Consider making usermode wizard operation a support mode
  (mostly for letting users upgrade things themself)

- Implement proper deploy log parsing; this basically means we
  need to be able to introspect Git Log. Consider using git-python
  for this.  There's also missing functionality, bad error handling
  and hacks in the prototype implementation of upgrade

- Wordpress needs to have .scripts dir in all -scripts versions
  (remember --no-walk!) (also make .scripts/.htaccess)
- Wordpress needs to have a .scripts/update script written for
  its latest version (do this after its migration)
- Wordpress needs to check for php.ini files (which it almost
  certianly has) and commit messages
- Wordpress needs user config and php.ini links made

- Summary script should be more machine friendly, and should not
  output summary charts when I increase specificity
- Check how many autoinstalls are missing w bits for
  daemon.scripts (this would need pyafs)
- Consider fixing Wizard's commit messages

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

PHILOSOPHY ABOUT LOGGING

Logging is most useful when performing a mass run.  This
includes things such as mass-migration as well as when running
summary reports.  An interesting property about mass-migration
or mass-upgrade, however, is that if they fail, they are
idempotent, so an individual case can be debugged simply running
the single-install equivalent with --debug on.  (This, indeed,
may be easier to do than sifting through a logfile).

It is a different story when you are running a summary report:
you are primarily bound by your AFS cache and how quickly you can
iterate through all of the autoinstalls.  Checking if a file
exists on a cold AFS cache may
take several minutes to perform; on a hot cache the same report
may take a mere 3 seconds.  When you get to more computationally
expensive calculations, however, even having a hot AFS cache
is not enough to cut down your runtime.

There are certain calculations that someone may want to be
able to perform on manipulated data.  As such, this data should
be cached on disk, if the process for extracting this data takes
a long time.  Also, for usability sake, Wizard should generate
the common case reports.

Ensuring that machine parseable reports are made, and then making
the machinery to reframe this data, increases complexity.  Therefore,
the recommendation is to assume that if you need to run iteratively,
you'll have a hot AFS cache at your fingerprints, and if that's not
fast enough, then cache the data.

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:

- A perfectly formed autoinstall with upgrade paths for all of
  the intervening versions is not really feasible to implement.
  As such, we want to migrate everything to -scripts, and then
  generate a -scripts2 with the correct .scripts directory.
  We will then nop update some installs, but this will prevent
  us from having to migrate and update concurrently.  Treat
  a scripts2 upgrade from migration the same way you would treat
  a botched scripts upgrade.

- 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.

- Full fledged logging options. Namely:
  x all loggers (delay implementing this until we actually have debug stmts)
    - default is WARNING
    - debug     => loglevel = DEBUG
  x stdout logger
    - default is WARNING (see below for exception)
    - verbose   => loglevel = INFO
  x file logger (only allowed for serial processing)
    - default is OFF
    - log-file   => loglevel = INFO
  x database logger (necessary for parallel processing, not implemented)
    - default is OFF
    - log-db    => loglevel = INFO

- More on the database logger: it will be very simple with one
  table named `logs` in SQLite, with columns: `job`, `level`,
  `message`.  Job identifies the subprocess/thread that emitted
  the log, so things can be correlated together.  We will then
  have `wizard dump` which takes a database like this and dumps
  it into a file logger type file.  The database may also store
  a queue like structure which can be used to coordinate jobs.

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
      /mitalso make .scripts/.htaccess/scripts/sec-tools/store/scriptslist
      This script might need to be adapted if we decide to nuke
      .scripts-version files.

    - The current install scripts will be kept in place, sans changes
      necessary to make them use Git install of copying the script over.
      Porting these scripts to Python and making them modular would be
      nice, but is priority.  For the long term, seeing this scripts
      be packaged with rest of our code would be optimal.

* 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)

    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. Remove all files from the working copy.  Use `wipe-working-dir`

    4. Download the new tarball

    5. Extract the tarball over the working copy (`cp -R a/. b` works well,
       remember that the working copy is empty)

    6. Check for empty directories and add stub files as necessary.
       Use `preserve-empty-dir`

    7. Git add it all, and then commit as a new pristine version (v1.2.3)

    8. Checkout the master branch

    9. [FOR EXISTING REPOSITORIES]
       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

       [FOR NEW REPOSITORIES]
       See if any patches are needed to make this run smoothly on
       scripts.

    [FOR NEW REPOSITORIES]
        mkdir .scripts
        echo "Deny from all" > .scripts/.htaccess
        touch .scripts/update
        chmod a+x .scripts/update

   10. Check if there are any special update procedures, and update/create the
       .scripts/update shell script as necessary (this means that any
       application specific update logic will be kept with the actual
       source code.  The language of this update script will vary
       depending on context.)

   11. Commit your changes, and tag as v1.2.3-scripts (or scripts2, if
       you are amending an install without an upstream changes)

   12. Test the new update procedure using
       `wizard upgrade --with=/path/to/repo /your/autoinstall` (this will
       read out master as your "latest" version).
       Use git commit --amend to fix any bugs (alternatively, squash them
       together later).

   13. You can also do a "mass" version of this using:
       `wizard -d testbed.txt massupgrade --with=/path/to/repo app`
       You'll need perms for any testbed stuff you want.

      GET APPROVAL BEFORE PROCEEDING ANY FURTHER

      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.

   14. 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.

   15. Run `wizard massupgrade appname`, which applies the update to all working
       copies possible, and sends mail to users to whom the working copy
       did not apply cleanly. It also frobs .scripts-version for successful
       upgrades (maybe not, depending on our plans).

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

* For mass importing into the repository, the steps are:
  (this probably won't ever be automated, becuase there are fiddly bits)

[TO SET IT UP]
# let app-1.2.3 be the scripts folder originally in deploydev
# let this folder be srv/
# you can also do a git clone
    mkdir app
    cd app
    git init
    cd ..
unfurl app-1.2.3 app  # [FIDDLY BIT]
# NOTE: contents of application are now in app directory
cd app
git add .
git commit -s -m "App 1.2.3"
git tag v1.2.3
git branch pristine
# NOTE: you're still on master branch
# WARNING: the following operation might require -p1
patch -p0 < ../app-1.2.3/app-1.2.3.patch  # [FIDDLY BIT]
# NOTE: please sanity check the patch!
git add .
# NOTE: -a flag is to handle if the patch deleted something
git commit -as -m "App 1.2.3-scripts"
git tag v1.2.3-scripts

[TO ADD AN UPDATE]
# let this folder be srv/app.git
git checkout pristine
# NOTE: this preserves your .git folder, but removes everything
wipe-working-dir .
cd ..
unfurl app-1.2.3 app  # [FIDDLY BIT]
cd app
# NOTE: please sanity check app directory
git add .
# NOTE: -a is to take care of deletions
git commit -as -m "App 1.2.3"
git tag v1.2.3
[FIDDLE AROUND. FIDDLE AROUND]
[IF THE PATCH HAS CHANGED]
    # You are on the pristine branch
    # 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 .
    # COMMENT: used to git checkout .scripts here
    # then check if the directory needs an updated update script
    # NOTE: Fake the merge
    git rev-parse pristine > .git/MERGE_HEAD
[IF THE PATCH HASN'T CHANGED]
    git checkout master
    git merge --no-commit pristine
git commit -as -m "App 1.2.3-scripts"
git tag v1.2.3-scripts

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

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

    - A .scripts directory, which contains the following information:

        * .scripts/update shell script (with the +x bit set appropriately),
          which performs the commands necessary to update a script.  This can
          be in any language.

        * .scripts/.htaccess to prevent this directory from being accessed
          from the web.

        * .scripts/database (generated) contains the database the
          user installed the script to, so scripts-remove can clean it

            XXX: Could cause problems if a user copies the autoinstall,
            fiddles with the DB credentials, and then scripts-remove's
            the autoinstall.  Possible fix is to add the original
            directory as a sanity check.  Additionally, we could have
            the application read out of this file.

        * .scripts/old-version (optional) the old value of .scripts-versoin

        * .scripts/install (eventually) interactively installs the
          applicatoin from command line.

* The autoupgrade shall be the process of:

    # Make the directory not accessible by the outside world (htaccess, but be careful!)
    git add -u .
    git commit -m 'automatically generated backup'
    git pull origin master
    if [ $? ne 0 ]; then git reset --hard; echo 'conflicts during upgrade'; fi
    ./.scripts/update
    # Make it accessible

  (with some more robust error checking, a proper dry run mechanism to, and
  lots of su'ing)

* Make 'wizard summary' generate nice pretty graphs of installs by date
  (more histograms, will need to check actual .scripts-version files.)

* Update AFS patch to advertise its existence, so we can check for it
  here.