I found many different solutions, some of them including EventMachine, which now is not necessary thanks to the new Sinatra 1.3 streaming feature.
The tricky part was related to the headers, the boundary, and the need to send the content type before each image.

For the test I first created a directory and stored some pictures inside

And the code. My little app looks like this:

Then simply create a Gemfile including Sinatra and Thin, as WebRick is not evented and does not support this kind of stream.

And that’s all. Run the app and you’re done.

Just visit http://localhost:4567/ with your browser :-)

Place this snippet after the body tag, and set your application (at facebook developers config center) to be auto-resizable. And that’s it!

Other common problem is how to make window scroll up when you click on a link. Usually the page renders but leaves you at the same vertical position you were before clicking.
If you are suffering this and you are using jquery, you can solve it this way:

Same as before, place this snippet after the body tag and you’re done.

I don’t remember where I got these snippets. Just wanted to share them because they’re really useful, and because I usually forget them and have to rescue backups of older apps heheh

Hope it helps!

Also, I am working in Ruby on Rails development since about 2 years ago. One of the things I have to do usually is to set up servers for hosting projects. And sometimes I have to set up a server for project development and tracking. These are the steps you can follow to set up a Ruby on Rails based server for development tracking.

1. Get a server

There are plenty of choices around the internet, some of them come completelly installed and prepared for deploying your app. They usually work the same way traditional LAMP hostings used to do, but using ssh key authentication instead of FTP sessions… some of them have also web based backend panels for deploying, migrating and managing your app gems.

I prefer to set up an empty GNU/Linux vanilla server, so that I can host everything I need, my way, no worries if PHP, Ruby or whatever. I can set up a relay mailserver, netfilter routing, traffic shaping, services for monitoring and differential backups that I can periodically rsync to my office local server. This is the way a sysadmin thinks, something that coders not always understand.

If you want to set up a development server I recomment you to take a look at most basic Linode VPS. Their control panel will let you run and destroy any Linux distro, setup and resize partitions, add failover addresses, disk space, processor and memory. And of course you’ll have full SSH root access. So I find it very useful and flexible for my needs.

Some considerations:

• You’ll have to set up a DNS name for the server IP, i.e: http://devel.somedomain.net
• You’ll need root access on the server. I’ll suppose you are working on a local computer, remotely logged via SSH to your server
• I usually build my servers using Debian (Lenny for now), but a basic knowledge of any other distro package system will let you adapt my guide to your preferred system
• I’ll suppose you’ve set up a specific environment for running your app on the development server (I usually call it beta)

2. Install screen

You may partially lose your work if for any reason your local computer hangs during the process. So it’s recommendable to install and use screen for working on a detachable console terminal. This way, if your computer shuts down, you’ll be able to boot again, ssh into your server and recover your screen session.

You’ll maybe want to set up your screen sessions to look nicer than withe on black, and give you some additional information of the remote system. I use a copy of the screenrc configuration file from my friend r0sk, it’s simple and nice and works sweet.

Enter screen

3. Base system

You’ll need an unprivileged user to host your web apps. I usually create a web user

Add contrib and non-free repositories to your Apt sources file (vim /etc/apt/sources.list)

Update your sources and then your system

Edit your SSH server config file to disallow root login and enable SSH key authentication (vim /etc/ssh/sshd_config)

Restart your SSH service

Install build-essentials for compiling and installing the environment dependencies

Install Postfix for using as MTA relay server, or MySQL Debian packages will install Exim (which I don’t really like)

4. Backports

Because of some software versions being old and deprecated on the APT sources, and some other not being present, an alternative repository can be set up for installing newer versions. The backports repository.

Edit your APT sources file (vim /etc/apt/sources.list)

Update your system again

5. MySQL

Install mysql service, and its ruby bindings package

Create a database for your project (mysql -uroot -p)

6. Ruby, Rubygems and Rails

Install the Ruby stuff, I prefer to use backports at this point to ensure latest versions.

Add unversioned links for the newly created binaries

Install Rubygems from source, so you can update it directly whenever you want. Otherwise the system will update it for you, only when new packages for your distro are available.

Link gem binary to an unversioned name

Update rubygems (not really needed, but just in case)

Install Rails

7. Image processing

Youll surelly want a plugin for cropping and thumbnailing images, maybe attachment_fu or paperclip. They both can work with Imagemagick.

8. Apache

There are different web server layouts for hosting your application. Some people likes Nginx+Mongrel, some other prefer Apache+Passenger, others prefer Nginx+Passenger… I love Apache. Maybe because its syntax simplicity, its flexibility or maybe simply because as a sysadmin I’ve been working for years with it.

Install Apache

Rename default virtualhost

Edit that virtualhost (vim /etc/apache2/sites-available/devel_somedomain_net)and configure it with the minimum options to work. I’m adding a basic HTTP authentication so only people you give the password can see your project (it’s a development server heheh).

Enable your new virtualhost

As the unprivileged user running the service, create the application directory and the HTTP Auth passwords file

Create the apache log directory for your app

Install Passenger

Create a file for loading passenger module into Apache (vim /etc/apache2/mods-available/passenger.load). Be careful with versions on the names as they may have changed.

Enable passenger module

Change the user and group executing Apache service to match your unprivileged user (vim /etc/apache2/envvars)

Restart Apache

9. Git and Gitosis

If you don’t want to pay a Github account and you don’t want your source to be visible to everyone, you’ll want to host your own Git server. There are different choices for that, but I like Gitosis because it’s simple and I can manage it from my command line, only editing a config file.

Install Git

Gitosis is written in Python, so you need to install python’s setup-tools in order to install Gitosis

Clone and install Gitosis

Create a new unprivileged user for hosting Gitosis and its repositories. It does not need a password (so it can’t log in) but it needs a shell as all management occours using an SSH session.

Upload your ssh public key to the server, leave it in /tmp/ and call it user@host.pub being user@host the final string specified into the file itself (ivan@mbp-local, or something similar)

Initialize Gitosis using the SSH key you just uploaded, which will be the Gitosis admin

In your local computer clone the Gitosis repository so you can manage it from now on

Enter the gitosis-admin directory and check the contents. It has to show a filename called gitosis.conf and a directory called keydir.

10. Add a repository for your app

Edit the Gitosis config (vim gitosis.conf) and add a new group, formed with one user (or more, separated with spaces), and its repository

Make sure to put user’s keyfiles into the keydir directory, following the previously mentioned format. Upload your changes.

In your local computer you can now create an application and add its files to the repo

11. Capistrano

You’ll want to deploy your software to your newly configured server. Capistrano is the best choice I know, since it creates versioned directories to let you roll back and forth, remotely run tasks on the hosted version of your app, place a custom “under maintenance” page, etc…

Install Capistrano

Capify your application

Create a recipe (vim config/deploy.rb)

12. SSH keys

In order to deploy your app without typing any password, you’ll have to set up a SSH key authentication between you and the unprivileged user of the server (web user).

Copy the content of your local ssh keyfile (commonly ~/.ssh/id_rsa.pub) and paste at the end of /home/web/.ssh/authorized_keys on the server. You’ll want to repeat this process for each developer so they can also deploy without typing a password.

You’ll also need to generate a SSH key for your web user on the server, and add it as a member of the repo in gitosis. Otherwise you won’t be able to deploy your app, because the server won’t let itself access to the repo for fetching.

13. Redmine

Redmine is one of those powerful tools that make your life easier when working with other developers, designers, webmasters and CEO’s… it helps you to keep tracking of issues, bugs, timings, files and documents, wikis and it also lets you graphically browse your repositories. If you’ve never tested it, now it’s your time.

NOTE: you’ll need to create a new entry on your DNS server. Set up a CNAME called redmine pointing to devel.somedomain.net

Redmine needs mod_rewrite support on Apache

You’ll need subversion to checkout the source code of Redmine

Su to your unprivileged user

Checkout the code

Create a database for redmine (mysql -uroot -p)

Edit Redmine’s database configuration file (vim config/database.yml)

Place a secret key for Redmine cookies on its environment file, inside the Initializer block (vim config/environment.rb)

Migrate the database

Edit the SMTP configuration for Redmine to be able to send notification emails (vim config/email.yml)

If you want to relay over Gmail or your domain’s email is hosted on Google apps, you’ll need to install a tls authentication plugin

Use this config for use with Gmail / Google apps

Exit su, and become root again

Create a new Apache virtualhost (vim /etc/apache2/sites-available/redmine_somedomain_net)

Create an Apache log directory for redmine

Enable your new virtualhost and restart Apache

14. Start writing Ruby on Rails

Here comes the funny part. Enjoy! ;-)

For my view:

The problem then is the resulting XML has not only escaped the HTML entities, but also latin characters (ie accents and tildes). After googling for an hour I’ve found some people blaming to_xs method (HTML escaped version of to_s, as its definition says) used for XML serialization.

Well, from the other app I need to parse this XML and get the original text. How the hell do I get latin chars unescaped again?

That’s it :-)

Once more I have to say: I’M LOVING VIM!!

Here is the PDF for downloading.

He mirado el registro del whois, y veo que el dominio ha caducado. Desde hoy mismo (23 de Abril 2009, día de Sant Jordi) pertenece a unos registradores masivos, de estos que te secuestran el dominio y luego te piden $15.000 por el.
Y desde luego la culpa no es de los bulk registers, sino del propietario anterior del dominio. Yo siempre me preocupo de renovar mis dominios antes de que caduquen.
Y es que en realidad el hecho de que se lo hayan quitado significa, no sólo que no se ha preocupado de renovarlo, sino que también se le ha pasado el periodo de redención (1 o 2 semanas, ahora no estoy seguro).

Bueno ahora la gran pregunta es dónde encontrar la documentación de la API, algo que uso a diario, y que ahora desde Gotapi no está disponible.

Qué es lo que ha pasado??? y ahora que????

EDIT: son las 20:31 y ya está funcionando again. No sé qué es lo que ha pasado, pero en 1 minuto se me ha venido el mundo encima. Se da uno cuenta de lo frágiles que somos, y lo delgada que es la cuerda sobre la que caminamos…

Hoy tenía un problema con el proyecto en el que estoy trabajando, y pedí a Mauro que me echase un cable a ver si entre los dos conseguíamos solucionarlo. Él estaba en su casa, y yo en la mía. Los ingredientes para cocinar un pair programming realmente fluído en remoto:

• Port forwarding: un puerto para el acceso remoto por SSH y otro para el acceso al servidor de aplicaciones (acceso web)
• screen: Usando una versión ligeramente modificada del screenrc de r0sk. Usamos tres consolas: [0] log del servidor, [1] vim con el código, [2] una bash para hacer accesos de mysql u otras cosas que necesitemos
• vim: con los controles mapeados para trabajar con tabs, y el plugin de FuzzyFinderTextMate para buscar y abrir archivos… así se puede hacer todo en una sola consola
• Skype: Para hablar todo el rato durante la sesión de programación

Los programadores maceros que usan TextMate suelen hacer el pair programming usando VNC, pero aunque no lo he probado pongo las dos manos en el fuego a que tiene que ser una cagada. La pareja screen+vim es brutal por lo lightweight y lo flexible, y consume muy poquito ancho de banda con lo que la comunicación del conjunto (ssh + skype) es perfecta.

La experiencia ha sido GENIAL, y hemos resuelto el problema en aproximadamente 1 hora. Es como trabajar en pair programming en local, tocando el mismo código y comentando todo el rato. Ha sido una pasada, y lo recomiendo a todos los programadores que trabajen separados físicamente del resto del equipo.

I’m working on an online app about auctions. A lot of the users coming to register don’t complete the email confirmation process, although I advise it in a red huge font at the login form. Most of the time I’m getting emils of users saying they registered but can’t login. When I look into the database, they didn’t activate their accounts.

Well, finally our CEO’s decided to remove the activation process. And this is when I’ve been googling for hours without luck, nobody explains the way to do it. Well no problem, it hasn’t been difficult at all. This is the way: a user is active if its activation_code in the database is Null.

• Edit models/user.rb and remove this filter

  before_create :make_activation_code
  

• In the same models/user.rb file, remove the activate method (we’re not activating any more user)
• In the same models/user.rb file, remove the make_activation_code method (it’s almost at the end of the file).
• Now edit controllers/users_controller.rb, remove completelly the activate method
• In the same controller/users_controller.rb file, in the create mehod, set the activated_at time before saving the user

  @user = User.new(params[:user])
  @user.activated_at = Time.now.utc  # <--- add this line
      if @user.save
      [...]
  

• Edit models/user_mailer.rb and completelly remove the activation method
• Remove the file views/user_mailer/activation.html.rb
• Edit the file views/user_mailer/signup_notification.html.erb and set the message as you like (variables are coming from models/user_mailer.rb)
• Restart your app and test

I'm sure there are better ways, and I'm not the best coder in the world, but this way works for me. Maybe it will help someone one day...

Se trata de Subastasde, un site dedicado a ofrecer información (tracking en realidad) de pisos y casas en subasta procedentes de embargos judiciales. Algunos ejemplos de lo que se puede encontrar:

• Subastas pisos
• Subastas de pisos en Barcelona
• Subastas de pisos en Madrid
• Y muuuuchos más pisos, apartamentos y casas que provienen de subastas y embargos judiciales (que de esto va la cosa)

El site no ofrece la posibilidad de pujar online, sino que se enfoca a un público profesional (subasteros básicamente), al que ofrece el seguimiento completo de los inmuebles que salen a subasta procedentes de los bancos. Después de la subasta si nadie lo ha comprado, el inmueble queda en estado de cesión durante un plazo corto de tiempo, que al expirar queda adjudicado a la entidad financiera. Entonces el banco tiene que venderlo a través de un API al modo de las inmobiliarias habituales.

En realidad no pretendo explicar aquí todo el detalle del proceso legal que sufren estos inmuebles. Lo que me interesa comentar es que este proyecto me ha dado la oportunidad de trabajar con una tecnología que era completamente nueva para mí.

Estoy orgulloso de poder decir que TODO el site es obra mía. Evidentemente he programado lo que los CEO’s me pedían, las ideas no han sido mías. Pero sí he programado toda la aplicación desde 0. He montado las bases de datos, he desarrollado los modelos y sus relaciones, los controladores, las vistas (compatibles IE6 y FFox a base de ostias), he aprendido Ajax (prototype y scriptaculous), javascript, he montado los servidores de desarrollo y de producción, con servicios que hasta ahora no había tocado… llevo un mes peleándome con los XML y otras técnicas SEO (I hate SEO!!), he aprendido Subversion y finalmente he migrado a Git. He tenido mi primer contacto con un sistema de tracking (usamos redmine)… y en definitiva puedo decir que mi vida como sysadmin poco a poco ha dado un giro radical desde hace un tiempo, una especie de metamorfosis o digievolución, para convertirme en coder de rails.
A todo esto, no puedo dejar de agradecer enormemente a mi amigo Mauro el tiempo y la paciencia que ha dedicado a ayudarme, cada vez que yo no me aclaraba con las API’s, cuando no tenía claro como debía hacer alguna cosa, o simplemente cuando caía en un agujero y no sabía como salir adelante. Gracias mussol :-)

Y en general todo esto me ha dado una ilusión nueva, me recuerda a mis inicios como administrador de sistemas, empapándome de documentación nueva cada día y peleándome con cada cosa que aprendía. Vuelvo a pasar las noches casi sin dormir, y siento que he recuperado la ilusión en un reto nuevo. Vuelvo a comprar libros, a leer listas de correo, a preocuparme por las versiones…
Y sé que hay muchísimos programadores mejores que yo, pero de eso se trata no? al fin y al cabo lo mismo pasa en sistemas.

Bien, así que a partir de ahora supongo que postearé más cosas relacionadas con Rails que con sistemas, y supongo que también iré informando de la evolución del proyecto, que dicho sea de paso tiene muy muy buena pinta.
Y ya sabéis, si queréis compraros un piso a la mitad de su precio de tasación, pasaos por Subastasde, porque cada día se incorporan nuevos inmuebles y algunos son verdaderos chollos.

Adjudicado! :-D