Zeropaste – the featureless pastebin

Tonight, when trying to compile Rubinius with Rubinius, I got some errors and wanted to report to relevant party. As usual, the log of what happened is required so I used my usual pastebin – pastie.org to send the logs. But then I noticed that the “Raw” link in it doesn’t provide an actual raw file anymore. What the fuck. It is now a html disguised as txt.

So I decided to whip up a new pastebin (because the world need one more pastebin) which doesn’t have any actual features (like tag highlighting, etc). I also learned the way to create shortest RESTful path possible (read: ‘/’).

There may or may not be more features coming. Developed in Rubinius because I can. Using mysql because of where it’ll be deployed at (see below).

I’ll get around deploying this soon after reinstalling VPS running this blog to Ubuntu or Debian. Running yum in a 128 MB box is suffering.

[ Source Code ]

Ruby 1.9, Rails, and UTF-8

(main purpose of this post is to link this “server error” page of rubygems.org)

The relevant issue in Rails Issue Tracker (3789). AFAICT, there are few ways to “fix” (read: workaround) this:

  • Modify the relevant Rack code to handle this crap
  • Create additional middleware to intercept (how?) the request (tried, either didn’t work or horribly inefficient)
  • Extend rack before it is started

Well, they all sucks. Hopefully someone comes up with actual working solution for this.

Oh, there’re another solutions:

  • Use REE 1.8 (really?)
  • Use JRuby in 1.8 mode
  • Use Rubinius (rbx 2.0 where?) in 1.8 mode

Um, yeah.

Update: I figured out how to “fix” it. Check it out in Moebooru (requires this).

Rails: read_multi and dalli

Be careful when using read_multi with dalli: it may return nil-valued key instead of the correct key.

The issue is tracked here and thanks to this I dropped the read_multi usage in moebooru and used the much simpler (and most likely slower) single fetch (per entry) instead. There’s alternative way to use it – do a read_multi and refetch whatever missing/nil-keyed but apparently I’m too lazy to do it.

Configuring SHA rounds for password in RHEL5/6

Due to NIH syndrome and Drepper being Drepper, the only remotely secure password hashing algorithm in RHEL5/6 is multi-rounds SHA512. The default is just salted SHA512 which sucks.

Also applies to CentOS, ScientificLinux, and other RHEL clones.

Anyway, to update the default setting, these files need updating:

  • /etc/login.defs: add new line SHA_CRYPT_MIN_ROUNDS 5000
  • /etc/pam.d/system-auth-ac: find line with `password    sufficient    pam_unix.so sha512` and append rounds=5000.

Note that the change to last file may or may not be persistent. I have no idea how to properly set it up.

Finally, run this command: authconfig --updateall.

If you’re using RHEL5, run authconfig --passalgo=sha512 --update first.

Moebooru 3.2

Finally reached the goal: Rails 3.2.6. The isn’t much change between 3.1 and 3.2 which is why I skipped 3.1. As there isn’t much front-end change, it means there isn’t any user-visible changes. Or at least there shouldn’t be.

Plans:

  • Move to jQuery
  • Use paper_trail for versioning (or something else)
  • Add SVG support (and maybe drop SWF support)
  • Actual news ticker
  • And more!

3.2.0 has been branched and currently running on some servers. The next version, 3.2.1 is on default branch and being tested on moe.myconan.net. As (finally) there are database changes, it will not be tested directly on live servers until it is stable enough.

Changes include better support for JRuby, use mini_magick instead of custom plug-in, less monkey-patches (but more bugs), and various clean-ups.

Rails 3.2 in Subdirectory

Steps to be into Rails in subdirectory:

Update config.ru to understand the subdirectory mapping:

run Moebooru::Application

change to

map (ENV['RAILS_RELATIVE_URL_ROOT'] || '/') do
  run Moebooru::Application
end

And then start Rails with correct environment variable (example if you use Unicorn):

RAILS_RELATIVE_URL_ROOT='/img' bin/unicorn

And that’s it. No need to mess with routes.rb as I previously thought after searching and experimenting for few hours. Links etc are properly generated with correct prefix. Or at least based on my quick testing.

May or may not work with earlier version(s) as I haven’t bothered to test it anywhere else.

Basic Dovecot/Postfix in Ubuntu

Configuring mail system is annoying. There are quite a bit different components which must be configured to work together.

My main choice for mail system is dovecot/postfix. As I don’t really understand how all this thing goes, I may have missed or misunderstood some parts. Or most of them. Feel free to correct this post.

For starter, most of basic configurations for Postfix and Dovecot has already been done by Ubuntu (or Debian) default configuration which includes enabling IMAP and TLS.

LDA

LDA (or MDA) delivers received mails to correct user and location. I let dovecot handle this thing because it’s easier this way. In /etc/postfix/main.cf:

mailbox_command = /usr/lib/dovecot/dovecot-lda -f "$SENDER" -a "$RECIPIENT"

Source ]

And that’s about it.

Maildir

The Mailbox format. The alternatives are mbox (ancient, shouldn’t be used anymore, I believe), or dbox (Dovecot only), or some other formats (which I don’t really care about). So basically I go with Maildir.

/etc/dovecot/conf.d/10-mail.conf:

mail_location = maildir:~/Maildir

[ Source ]

SASL

The last one, Postfix authentication. I use Dovecot SASL because it’s easier.

/etc/postfix/main.cf:

smtpd_sasl_type = dovecot
smtpd_sasl_path = private/auth
smtpd_sasl_auth_enable = yes
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination

/etc/dovecot/conf.d/10-master.conf:

unix_listener /var/spool/postfix/private/auth {
  mode = 0666
}

[ Source ]

For Dovecot config, it’s usually already in there, one just uncomment it to enable.

Restart Dovecot and Postfix, and that’s it. As I mentioned before, Ubuntu has preconfigured many things which leaves me only few additional tasks to be done to enable simple mail system (with TLS, IMAP, and whatnot).

Protip: use Google Apps or Live Domain instead of managing your own mail server.

Disabling Upstart Service in Ubuntu (11.04+)

Took me few weeks to find out that this one-liner does wonder:

echo manual >> /etc/init/mysql.override

(the line above is to disable mysql, obviously. And must be done as root)

The answer is on first hit (as of this post’s writing) of googling “ubuntu disable service” but you need to scroll down a bit and ignore shitload of crappy, outdated explanations to find that small gem.

Unfortunately doesn’t apply to previous LTS. Or does it?

Moebooru/Rails 3, and more

After working on it for several weeks, finally it got to the point where it’s relatively usable. No more Bundler-on-Rails2 evilry and the fact that 3.0 branch is still supported.

The best part is the one above. Yes, Moebooru now runs on Rubinius/Puma. The only foreseeable problem is it uses Process.pid on file uploads which, when several people uploading (or working with) files at same time, the temporary filename will collide.

Though due to me aiming more for workable implementation instead of correct implementation, there are quite a lot legacy stuff still in there:

  • repeated_auto_complete doesn’t work in Rails 3 without vendoring or updating the gem itself  (and I did both since Bundler’s git functionality seems broken in Rubinius).
  • prototype_legacy_helper must be used since I haven’t had time to upgrade the *_remote functions (and still thinking how to do it).
  • verification gem since I haven’t upgraded the route and its functionality, which previously built-in in Rails 2.3 has now removed.
  • Unsightly lib/core_ext. Just look at evilry I have added to make it behave like 2.3-stable.

On the brighter side, now I can start cleaning up the code. Or upgrade all the way to Rails 3.2 ( ¬‿¬)

Optimize all the queries!

While digging more into the code called “Moebooru” which was forked from “Danbooru”, I noticed this:

def self.included(m)
  m.extend(ClassMethods)
  m.after_create :increment_count
  m.after_destroy :decrement_count
end

def increment_count
  connection.execute("update table_data set row_count = row_count + 1 where name = 'users'")
end

def decrement_count
  connection.execute("update table_data set row_count = row_count - 1 where name = 'users'")
end

Counting takes ages, right. Except it is not. I’ve done this, yes, but on a table with 10+ millions of data (this one has ~400k in mainline danbooru), with multiple data inserted (this one got, uh, one every other week?) and queried every second (see below), and with the required count method not a simple select count(1) on some_table (which is what the example above used for).

The best part? It’s only used once, when user registers:

def set_role
  if User.fast_count == 0
    self.level = CONFIG["user_levels"]["Admin"]
  elsif CONFIG["enable_account_email_activation"]
    self.level = CONFIG["user_levels"]["Unactivated"]
  else
    self.level = CONFIG["starting_level"]
  end

  self.last_logged_in_at = Time.now
end

Moebooru Update

I haven’t been able to work on Moebooru for most of this month but I got to work on it this weekend. At ~30 changes, it went from -alpha to -beta.2 after receiving good amount of tests.

Summary of changes (more or less):

  • Most instances of RAILS_ENV and RAILS_ROOT have been replaced with newer Rails.env/Rails.root
  • Better Javascript handling in Development mode by moving cached Javascript from application.js to cached/all.js
  • Removed AssetCache modification library
  • Replaced HTML5Sanitizer’s html5sanitize with Rails’ built-in sanitize (because the former doesn’t work in 1.9)
  • Fixed Note Editor’s “History” button
  • Fixed Comment page’s pagination
  • Fixed Tag Relation search function
  • Updated “hack” for UTF-8 handling in Rails 2.3 with Ruby 1.9
  • Merged updates from moe branch
  • Reverted change which put class definition in <html> tag as it currently required by Javascript

Moebooru rebased

Since I forgot to branch the original source, the branching looked awesomely crappy. Therefore I decided to rebase entire thing to ease up keeping track with Moebooru “mainline”. All my commits are now in branch “default”. If you didn’t do any change, backout up to revision 9174b6b5b02d and then pull again. And then, don’t ever touch moe branch again anymore.

moebooru again

Last week I posted about my random project which involves modernizing moebooru without doing complete rewrite (see this for yet another complete rewrite attempt).

Let’s revisit the plan:

  • Upgrade to Ruby 1.9: done, need testing.
  • Update all plugins: mostly done, can use some trimming.
  • Update anything deprecated: nope
  • Migrate to Bundler: done, not sure how to test.
  • Use RMagick instead of custom ruby-gd plugin: nope
  • Use RMagick instead of calling jhead binary: nope
  • And more!: I hope you didn’t expect me to do more while there are incomplete items above.

Sure looks good. Need more testing though. There’s also one part which I totally had no idea why should be changed when upgrading to 1.9. Just grep for FIXME to see which it is and hopefully fix it up for me (or explain what it does).

As usual, having completed the work for today, live demo is up and open for everyone to break (…if there’s anyone, that is).

[ Live Demo | Repository ]

bcrypt in Debian

WARNING: using method below will lock yourself out when using emergency console since whatever crypt it’s using surely doesn’t understand bcrypt (as I experienced myself). Additionally, this solution won’t add bcrypt support to other applications using crypt interface like proftpd unless it’s started by preloading libxcrypt.so first (also from my own experience).

As much as Drepper want to pretend bcrypt is wrong solution, it actually gives one benefit: ease of switch to Linux. Some systems use bcrypt by default or configurable to use it. On other case, there might be time where you need system’s (or applications using system’s) crypt to handle bcrypt passwords from external system (usually web applications).

It’s quite difficult to enable bcrypt support in RHEL based distro as there is no libxcrypt and pam_unix2 packages available. Thankfully it’s available in Debian (and derivatives) in package libpam-unix2.

The README.Debian says to modify files in /etc/pam.d but if I remember it correctly, it confused apt PAM handling system or whatever. Fast forward few weeks, I discovered a better way to use it by creating PAM configuration in /usr/share/pam-configs. Since it’s mostly equivalent to normal pam_unix, I just copy and modify the file using this (long-ass) oneliner sed:

sed -e 's/pam_unix.so/pam_unix2.so/g;s/^Name: Unix authentication$/Name: Unix2 authentication/;s/pam_unix2.so obscure sha512/pam_unix2.so obscure blowfish rounds=8/;s/ nullok_secure//' /usr/share/pam-configs/unix > /usr/share/pam-configs/unix2

Then execute pam-auth-update, select Unix2 authentication and deselect Unix authentication. Don’t forget to update passwords for all other users as well or they won’t be able to login since pam_unix2 doesn’t recognize sha based hashes.

Actually, change all other users password to use md5 first before replacing the PAM with pam_unix2.

Update 2012-04-01: Removed nullok_secure since it isn’t supported.

Update 2012-06-09: Added warning.

An Attempt to Update moebooru Engine

If you didn’t know, the current moebooru running on oreno.imouto is using ancient version of many things. It also uses a custom lighty module (mod_zipfile) which doesn’t seem to be available anywhere.

I’ve updated it with latest Rails 2.x and made it compatible with nginx. Mostly. You can see it running here.

The plans:

  • Upgrade to Ruby 1.9.
  • Update all plugins.
  • Update anything deprecated.
  • Migrate to Bundler.
  • Use RMagick instead of custom ruby-gd plugin.
  • Use RMagick instead of calling jhead binary.
  • And more!

We’ll see if I can actually finish this one. Grab the source here. Yeah, I’m using Mercurial for a Rails project.

Compiling PuTTY for Windows

Because of one awesome bug inflicts eye-cancer when using Consolas font and deactivated “Bold text is a different colour”, I had to recompile PuTTY by hand (more like, by gcc). I initially tried to compile the PuTTYTray one but apparently they successfully mixed C and C++ code and completely broke the build procedure using mingw. Or I missed something obvious.

Anyway, I went back to vanilla PuTTY. As it turns out, compiling using latest mingw’s gcc isn’t a good idea since it removed -mno-cygwin option and therefore broken unless you do some magic edit. Thanks to that, I stopped bothering trying to compile it under Windows and used mingw-gcc for Linux (which is able to produce Windows binary). Here be the steps from beginning. Tested on Debian 6.

apt-get install mingw32 subversion perl
svn co svn://svn.tartarus.org/sgt/putty putty
cd putty
perl mkfiles.pl
cd windows
make VER="-DSNAPSHOT=$(date '+%Y-%m-%d') -DSVN_REV='$(svnversion)' -DMODIFIED" TOOLPATH=i586-mingw32msvc- -f Makefile.cyg putty.exe

Patch is done before make (duh) and the diff can be found here. If you’re lazy (like me) you can just download the build at my server (link at bottom). Should be virus-free but I guess you can notify me if you encounter one. Built everyday until it breaks.

  • exe: the program
  • sha512: hash of the program
  • zip: both program and its checksum

[ exe | sha512 | zip ]

Debian’s sources.list

I kept forgetting them whenever I need one so I’ll put mine here and be happy:

###### Debian Main Repos
deb http://http.debian.net/debian squeeze main contrib non-free
#deb-src http://http.debian.net/debian squeeze main contrib non-free

###### Debian Security Update Repos
deb http://security.debian.org squeeze/updates main contrib non-free
#deb-src http://security.debian.org squeeze/updates main contrib non-free

###### Debian General Update Repos
deb http://http.debian.net/debian/ squeeze-updates main contrib non-free
#deb-src http://http.debian.net/debian/ squeeze-updates main contrib non-free

###### Debian Backports Repos
deb http://http.debian.net/debian-backports squeeze-backports main contrib non-free
#deb-src http://http.debian.net/debian-backports squeeze-backports main contrib non-free

###### Dotdeb Repo
#deb http://packages.dotdeb.org squeeze all
#deb-src http://packages.dotdeb.org squeeze all

It should cover mostly used packages and will keep me sane. Also debian-volatile has been replaced with debian-updates (god knows why it’s called like that) since squeeze (6.0) but in case I need to take care a lenny or earlier (derp) machines, this should also be added:

deb http://volatile.debian.org/debian-volatile lenny/volatile main contrib non-free

Oh and Debian/kFreeBSD within a FreeBSD system is quite funny.

Update 2012-12-27: Use improved CDN.

Daily craps

  • LOL U-U-Uma Uma. Not good for health.
  • Noizi Itou drew the cover.
  • LAWL 22MB PNG. Perhaps I should mirror moe.imouto/noizi_ito…
  • a manga with nijikon main character. Recommended. LOL.
  • wat.
  • Danbooru 1.14.0 has released. I still wonder what “Final tagged version” means. And I think I’ll use tagged ones instead of trunk from now on. Why? Just because. 😛
  • ^– actually, it means less maintenance.
  • With that, I’ll also stop using -current for animu server o.o
  • Not before 4.4 released though – which means I’ll have to struggle with -current until November – or until I switch to NetBSD. The reason is simple: Danbooru requires PostgreSQL 8.3 which only available as package on -current (I forced to manually compile before using -current). – Or maybe until I switch to Shimmie (which sucks).

FreeBSD: 0, NetBSD: 1, OpenBSD: 1

Sil3112 (SiliconImage SATALink RAID PCI Card) is not properly supported by FreeBSD. The installer halted successfully on all my three attempt at installing it. (First one even stopped when formatting – said that it can’t find the hard disk drive LOL).

OTOH, NetBSD and OpenBSD can use that piece of hardware just fine albeit the claim of the card as “crappy” on certain mailing lists.