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Rails migration for acts_as_authenticated plugin

The following shows a typical Rails migration for creating the users, roles and role_users table for the acts_as_authenticated plugin. Note that an initial admin user with a default password is added: class CreateRolesAndUsers true do |t| t.column :login, :string t.column :email, :string t.column :crypted_password, :string, :limit => 40 t.column :salt, :string, :limit => 40 t.column :created_at, :datetime t.column :updated_at, :datetime t.column :remember_token, :string t.column :remember_token_expires_at, :datetime end create_table :roles, :force => true do |t| t.column :name, :string, :limit => 40 t.column :authorizable_type, :string, :limit => 30 #t.column :authorizable_id, :integer t.column :created_at, :datetime t.column :updated_at, :datetime en...
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Systems Management: A time saver

Systems Management in Rails is a rails application for keeping track of computer inventory and also allows the user to execute remote ssh commands, wake on LAN, vnc and remote desktop on them. I developed it to help distribute software to all the machines at my work in a easy way. It uses the OpenAudit database (populated of course by the OpenAudit scripts) with some added changes such a new column in the systems table for type of password and a new table to keep the ssh commands history. Software distribution is done this way: User specify which file to send to which machines and the command to be run when the upload is successful The file is uploaded using sftp The command is executed using SSH. Systems Management also allows the user to access a computer via VNC or RDP by just clicking on a link. You can download it from http://rubyforge.org/projects/managesystems/
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Script to generate an RSS feed from RenWeb's announcements

The following ruby (jruby) and sql code will get the Announcements from RenWeb and create an RSS feed file from them. The scripts needs the JDBC ActiveRecord gem. If you have any questions on how to run this script, please write a comment below. Both files are released under the MIT license . main.rb: require 'rss/maker' require 'cgi' require 'rubygems' gem 'activerecord-jdbc-adapter' require 'jdbc_adapter' class AnnouncementsDistrict :jdbc, :username => "YOUR ODBC USERNAME", :password => "YOUR ODBC PASSWORD", :driver => "com.microsoft.sqlserver.jdbc.SQLServerDriver", :url => "jdbc:sqlserver://THE URL TO CONNECT;DatabaseName=YOUR DATABASE NAME") set_table_name("AnnouncementsDistrict") #Gets an sql query from a file def self.get_sql_query_from_file(filename, params_hash_for_sql_query = nil) fi = File.open(filename) sql_query = fi.read if pa...
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How to create a yahoo datatable in rails

To create a Yahoo Ajax Datatable (with local datasource) from a rails view, I had to do the following. First I had to add this helper method to the Application controller: module ApplicationHelper #Outputs the javascript code necesary to create a yahoo datable # from a plain datasource # column_array: and array of 2-item arrays in the form: # ["name_wihout_spaces", "Text to show in the column header"] # data_rows: an array or rows. Each row is an array that has the values in the # order specified in the column_array. def to_yahoo_array_data_source(column_array, data_rows, custom_div_id = "myContainer", custom_col_var_name = "data_cols", custom_datasource_var_name = "data_source") column_items = [] column_array.each do |column| column_items Next I added the required javascript libraries to the application layout: <html> <head> <title>Email De...
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Strange behavior with the up,left,space bar key combo

I was checking if the up and left arrow and the space bar was pressed in my game code to allow the player to move and turn and shoot at the same time. Turns out that in GameMaker 7, if the user holds up+left+space bar keys at the same time, either the up or the left arrow key event will be ignored. I had to change the shoot key to the key to go around this weird behavior.
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Math game for Areas and Volumes

I just uploaded an educational game to YoYoGames called Math Areas and Volumes . The game was made using GameMaker and the original purpose for it was to help my eight grade student to improve their skills of finding the area and volume of objects. If you have ever taught children about areas and volumes, you probably will notice that some of them confused the two concepts. The game uses plain graphics to help students distinguish the difference between the area and volume concepts. A 2D square with little squares filling it, represent a square unit. A 3D cube with little cubes on it represents the cubic units. You would need to play it to completely get the idea of what I was trying to do to help the students. Something else worth noting is that I used some of the excellent graphics that came with my Multimedia Fusion. I already asked in the forum, and the official response was that I could use the graphics as long as distributed the game only as an “.exe”. Thank you Clickteam!
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Warbler uses gem files from cache folder instead of gems folder

I was having the following error when running warbler war on my rails application folder: Cannot load gem at [/home/juanito/jruby-1.1.4/lib/ruby/gems/1.8/cache/activerecord-jdbc-adapter-0.8.2.gem] in /home/juanito/bulletonrails/svn_copy/bullet_gui /home/juanito/jruby-1.1.4/lib/ruby/site_ruby/1.8/rubygems/format.rb:41:in `from_file_by_path' I looked around the gems/1.8/cache folder and sure enough, the gem file for activerecord-jdbc-adapter was missing. I had deleted that file and other gem files from that folder a while ago because I thought I would not need them and they was taking space. Well, it turns out that Warbler uses the gem files from the rubygem's cache folder to unpack the gems into the WEB-INF folder. As a consequence, by basically using the original gem files, it bypasses any modification you make to your local gems. So if your newly deployed jruby WAR application is missing custom behavior that you added to your local gems, you may want to convert the gem...
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Make your rails app launch the web browser when starting

In jruby, if you ever want to start the browser pointing to your application's base index page after rails finishes initialzing your application, you can take advantage of java.awt.Desktop::desktop.browse. java.awt.Desktop::desktop.browse will open the default OS's browser and point it to an URL you pass to it (tested on Windows, failed in Ubuntu+Firefox, don't know if it works on MacOSX or Solaris). Add these lines at the end of environment.rb to launch the browser: include Java java.awt.Desktop::desktop.browse( java.net.URI.new('http://localhost:3000'))
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How to make Net::SSH work with Jruby on Windows

Net::SFTP works like a charm in Jruby on Linux. However, when I tested my application in Windows, I ran into a fail "to load -- dl/import ssh" error and then into "IOError (The system cannot find the path specified)". To work around the errors, I had to make some changes to the Net::SSH code to make it work. There are 2 files you need to change gems\net-ssh-2.0.4\lib\net\ssh\known_hosts.rb and gems\net-ssh-2.0.4\lib\net\ssh\authentication\pageant.rb. For known_hosts.rb change the add(host, key) method located at the end of file to read like this: # Tries to append an entry to the current source file for the given host # and key. If it is unable to (because the file is not writable, for # instance), an exception will be raised. def add(host, key) begin #jpt File.open(source, "a") do |file| blob = [Net::SSH::Buffer.from(:key, key).to_s].pack("m*").gsub(/\s/, "") file.puts "#{host} #...
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Java-jruby program to turn on computers remotely

Using wakeonlan.rb from Kevin R. Bullock, I was able to creat a small jruby swing-gui program for turning on remote computers using Wake On LAN. The program displays in an array buttons corresponding to the computers listed in a text file. When you click the button, the program sends a WOL packet to the computer to turn it on. The code is the following (note that you need wakeonlan.rb in the same folder): # Copyright (c) 2008 Juan Pablo Tarquino # # Permission is hereby granted, free of charge, to any person # obtaining a copy of this software and associated documentation # files (the "Software"), to deal in the Software without # restriction, including without limitation the rights to use, # copy, modify, merge, publish, distribute, sublicense, and/or sell # copies of the Software, and to permit persons to whom the # Software is furnished to do so, subject to the following # conditions: # # The above copyright notice and this permission notice shall be # included in al...
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New Avery 5160 template for Jasper Reports

I had to create an Avery 5160 (address labels 3x10) template for jasper for work. If you would like to use that production-ready template you can download it from here . The template has been used in a production environment, however, as always, make sure it works for you before printing too many labels :).
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Ruby script to get a batch of MARC records

At work we bought a lot of new books for our new library. Our libraries use aprogram called LibraryPro which can import MARC records to add books to the catalog. To save ourselves some time, I look on the web for a script to get MARC records from the Internet and found this excellent script from William Denton. Because I needed to get batches of records and modify the records gotten to follow our custom dewey decimal number (number/category/author), I modified his script to accomplish that and this is how it looks now: #!/usr/local/bin/ruby -w # Script to get a batch of MARC records # #original code taken from http://www.miskatonic.org/library/zmarc.html # original programmer # William Denton wtd@pobox.com # April 2007 # modifications made by Juan Pablo Tarquino http://jptarqu.blogspot.com # Released under the MIT License. # Copyright (c) 2007 William Denton # Copyright (c) 2008 Juan Pablo Tarquino # # Permission is hereby granted, free of charge, to any person # obtaining a cop...
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Update on Tomcat on SSL

At work, I set up Tomcat 6.0.16 to use SSL using the instructions from http://techtracer.com/2007/09/12/setting-up-ssl-on-tomcat-in-3-easy-steps/ . However, I had to modify some of the steps to make it work on mys system: When generating the Keystore file, make sure you tell keytool that you wnat RSA: keytool -genkey -alias techtracer -keypass yourpassword -keystore techtracer.bin -storepass yourpassword -keyalg RSA Also, in tomcat's sever.xml, use the code snippet from the official documentation (http://tomcat.apache.org/tomcat-6.0-doc/ssl-howto.html) instead of his snippet, e.g.: < connector port="8443" minsparethreads="5" maxsparethreads="75" enablelookups="true" disableuploadtimeout="true" acceptcount="100" maxthreads="200" scheme="https" secure="true" sslenabled="true" keystorefile="/home/yourself/apache/webapps/techtracer.bin" keystorepass="yourpassword...
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Deployed a JRails application using warbler in Apache

I was able to deploy a JRails application using warbler in Apache. The latest warbler gem is very nice and stable. I just needed to make sure warbler and jar were in my PATH variable. I also had to tell warbler to generate the files outside my truecrypt drive because somehow, truecrypt was not allowing WEB-INF folder to be uppercase. I still can't figure out how to change the Rails environment from Production to Development, it seems that warbler forces you to use Production which is very understandable considering that you usually deploy to production servers. Futhermore, thanks to the excellent Setting Up SSL on Tomcat In 3 Easy Steps article by nitinpai, i was able to set up apache and the rails application to run under SSL. Very, very nice and it was incredible easy, however, to make the certificate work with firefox 3 you need to tell keytool to use RSA. The is another article on the web about that, you can google it.
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New Label templates for JasperReports

I had to create jasper templates for Avery 5390 and 5388 at work, so I decided to share the templates with those of you who are looking to print labels from iReport and/or JasperServer. You can download the templates here (includes 5390, 5388 and 5960) . The templates have a square where you should be able to safely put your content. I came up with the squares' dimensions by trial and error so please do some trial printings to see if it works for you. Also, groovy is the default language in my iReport so for all my templates had the language attribute set to groovy; if you run into problems with jasperserver you can do either one of the following: Place the groovy jars in JasperServer's webapp's lib folder. OR Edit the templates to disable groovy (remove the language="groovy" attribut from jasperReport node). Many thanks to André for pointing that out! The templates are released under the MIT license.
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How to create customized, windows installers of Tomcat server

To create customized, windows installers of Tomcat server (including an option to allow the user to install it as a windows service) you can modify the ".nsi" installation script provided in the " res " folder. You can find the res folder when you download Tomcat's source code. For more information on nsi scripts please visit http://nsis.sourceforge.net/Main_Page .
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Securely erase files and folders recursively in Linux

This ruby script will securely erase files and folders recursively in Linux. You may want to add a action to run this script to the context menu of Nautilus using nautilus-actions . # # Shreds files and folders recursively. Code released under MIT license. NUMBER_OF_PASSES = 20 def shred_files_and_folders(path) if File.directory?(path) files = Dir.entries(path) files.delete_if {|x| x == "." or x == ".." } files.each do |f| if File.directory?(path + '/' + f) shred_files_and_folders(path + '/' + f) else puts ` shred -v -z -u -n#{NUMBER_OF_PASSES} #{path + '/' + f}` end end Dir.rmdir(path) else puts ` shred -v -z -u -n#{NUMBER_OF_PASSES} #{path}` end end ARGV.each do |path| shred_files_and_folders(path) end
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Script to delete old backups files created with Cobian Backup

The following ruby code will delete from a folder old backups files created with Cobian Backup. The deletion is recursive, so all the folders within the folder will be cleaned. # # Deletes old backups made with Cobian Backup. This code is released under the MIT license. NUMBER_OF_FILES_TO_KEEP = 6 def delete_old_backups(path) files = Dir.entries(path) files.sort! {|x,y| y x } files.delete_if {|x| x == "." or x == ".." } name_of_file = " " new_name_of_file = "" file_cnt = 0 files.each do |f| puts f new_name_of_file = f.split(" ")[0] if new_name_of_file != name_of_file file_cnt = 0 name_of_file = new_name_of_file end if File.directory?(path + '/' + f) delete_old_backups(path + '/' + f) end file_cnt = file_cnt + 1 if file_cnt > NUMBER_OF_FILES_TO_KEEP puts "delete " + path + '/' + f File.delete(path + '/' + f) end en...
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