<%= render(:partial => 'controller_s_directory/partial', :locals => {...}) %>

Another very interesting thing I found out (perhaps quite obvious, but I was delighted): partials can functions as methods, and can be used for recursion! You can call the partial from inside itself! =) This was extremely helpful for me, I hope it will also be for somebody else…! And one last thing, most certainly obvious as well, but always good to be reminded: the render command, when used inside a view, *has* to come surrounded by <%= %>. The equal sign is extremely important! You can’t, for instance, have some ruby code inside <% %> and call render there. You have to close the block and open a new <%= %>… =)

$ id user1
uid=1000(user1) gid=1000(user1) groups=1000(user1),\
4(adm),20(dialout),24(cdrom),25(floppy),29(audio),\
30(dip),44(video),46(plugdev),104(scanner),\
108(lpadmin),109(admin),115(netdev),117(powerdev)
$ sudo usermod -aG adm,dialout,cdrom,floppy,audio,\
dip,video,plugdev,scanner,lpadmin,admin,netdev,\
powerdev user2

$ sudo apt-get install ntfsprogs

$ sudo mkntfs /dev/sdb1

$ sudo gem install mysql
[sudo] password for user:
Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
ERROR: Failed to build gem native extension.

/usr/bin/ruby1.8 extconf.rb install mysql
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lm... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lz... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lsocket... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lnsl... yes
checking for mysql_query() in -lmysqlclient... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/usr/bin/ruby1.8
--with-mysql-config
--without-mysql-config
--with-mysql-dir
--without-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib
--without-mysql-lib=${mysql-dir}/lib
--with-mysqlclientlib
--without-mysqlclientlib
--with-mlib
--without-mlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-zlib
--without-zlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-socketlib
--without-socketlib
--with-mysqlclientlib
--without-mysqlclientlib
--with-nsllib
--without-nsllib
--with-mysqlclientlib
--without-mysqlclientlib

Gem files will remain installed in /usr/lib/ruby/gems/1.8/gems/mysql-2.7 for inspection.
Results logged to /usr/lib/ruby/gems/1.8/gems/mysql-2.7/gem_make.out

Solution? I found in Ubuntu Forums, and it solved the problem.

sudo apt-get install libmysqlclient15-dev

$ ssh -D localhost:PORT user@remote_host

Then you edit Firefox proxy settings (Edit menu, Preferences, Advanced, Network, Configure how Firefox conects to the internet (Settings…), Manual proxy configuration) and add localhost to SOCKS host, and the PORT you passed to your ssh command. To tunnel DNS traffic as well, set network.proxy.socks_remote_dns property in about:config to true. =)

lucas@bonito:~/my_rails_proj$ rake stats
(in /home/lucas/my_rails_proj)
+----------------------+-------+-------+---------+---------+-----+-------+
| Name                 | Lines |   LOC | Classes | Methods | M/C | LOC/M |
+----------------------+-------+-------+---------+---------+-----+-------+
| Controllers          |  1687 |  1306 |      13 |     108 |   8 |    10 |
| Helpers              |   244 |   223 |       0 |      13 |   0 |    15 |
| Models               |   682 |   550 |      12 |      34 |   2 |    14 |
| Libraries            |     0 |     0 |       0 |       0 |   0 |     0 |
| Components           |     0 |     0 |       0 |       0 |   0 |     0 |
| Integration tests    |     0 |     0 |       0 |       0 |   0 |     0 |
| Functional tests     |   364 |   262 |      24 |      50 |   2 |     3 |
| Unit tests           |   120 |    84 |      12 |      12 |   1 |     5 |
+----------------------+-------+-------+---------+---------+-----+-------+
| Total                |  3097 |  2425 |      61 |     217 |   3 |     9 |
+----------------------+-------+-------+---------+---------+-----+-------+
  Code LOC: 2079     Test LOC: 346     Code to Test Ratio: 1:0.2

And you can see very easily that my testing skills need to improve a lot… Quite a lot! =P And by the way, Google’s Search History can be amazingly useful… =)

I had absolutely no idea what it meant, besides the obvious, which didn’t help me to solve the problem. I tried checking error logs, forums, etc. The weirdest thing was that it apparently had no pattern, it looked very random. I could use my app for entire weeks and nothing would go wrong, then all of a sudden, there it was…

I’ve installed LiveHTTPHeaders to better analyze what was being sent to server in the requests, and what exactly I was getting back as a response. Peter Kwan, from ASE, always very very helpful, pointed out a few things to me: that CD uses some parameters of its own to process AJAX updates, for instance zooming, moving, etc. To prevent the URL from getting too long, it limits the length of user parameters. The problem was that sometimes CD was cutting the URL right after a “%“, which is a escape character. With normal text after it (CD’s parameters) rather than a sequence to be escaped, Mongrel (I use Ruby on Rails) returns an error (“HTTP parse error, malformed request” and “HttpParserError: Invalid HTTP format, parsing fails.”). Most web servers would just ignore the incorrect escape sequence, but Mongrel is designed not to tolerate any invalid URL.

Solution: make my URL shorter, replacing parameter names like timestamp by t, for instance, or group many parameters in one, separating them with comma or something like it. Another one is to add the line:

query = query[0..240] + "00"

to file chartdirector.rb, right below line 1569, which should be:

path, query = @request.request_uri.split('?', 2)

This prevents invalid escaped sequences from being sent as a request, adding “00″ to the end of the “cut”… And everything works fine! Thanks once again for great and always helpful Peter Kwan, who makes using ChartDirector and solving problems a kind of pleasent task… =)

var myCombo = new Ext.form.ComboBox({
emptyText: 'Select',
editable: false,
fieldLabel: 'Combo box',
mode: 'remote',
forceSelection: true,
selectOnFocus: true,
store: myStore,
triggerAction: 'all',
valueField: 'key',
displayField: 'value',
 hiddenName: 'myCombo',
 name: 'myCombo',
width: 98,
allowBlank: false
});