Photographed by Abllo™

Red ant i found on a tree..

– License

The attachment_fu plugin written by technoweenie takes care of uploading and retrieving files using S3 and CloudFront, it has other options too such has saving to the database, local file system, rack space. Anyways in this post I describe how to use the plugin with S3 and CloudFront

1. Create a sample rails project.
2. Install aws-s3 gem, ‘sudo gem install aws-s3‘.
3. Install attachment_fu plugin “./script/plugin install git://github.com/technoweenie/attachment_fu.git“.
4. Assuming that you already have an Amazon S3 account, create a new S3 bucket.
5. Next step is to sign up for the Amazon CloudFront, this is Amazon’s CDN and like any other AWS you pay for what you use, in addition it integrates with your S3 buckets.
6. Now log into the CloudFront’s console and create a new distribution channel that is backed with the S3 bucket created in above steps.
7. Rename amazon_s3.yml.tpl to amazon_s3.yml (it will be in your config folder)
8. Edit the amazon_s3.yml file and fill in the appropriate information.
9. Make a model ‘./script/generate model file_meta_data size:integer content_type:string filename:string’ .
10. Edit the newly created model and add the following lines to it.( ‘has_attachment’ and ‘validated_as_attachment’ are provided by the plugin, there are many other options that you can specify to read more on the options refer to this page).

has_attachment   :storage => :s3,
:cloudfront => true
validates_as_attachment

11. Generate controller ‘./script/generate controller Upload index show new edit create update destroy’.
12. Edit the Upload controller and add the following

def index
@fileMetaDatas = FileMetaData.all
end
def new
@fileMetaData = FileMetaData.new
end
def create
@fileMetaData = FileMetaData.new(params[:fileMetaData])
if @fileMetaData.save
flash[:notice] = ‘File was successfully created.’
redirect_to :controller => :upload, :action => :index
else
render :action => :new
end
end

13. Edit the new.erb.html file under the upload controller folder and add the following

<% form_for(:fileMetaData, :url => upload_file_path, :html => { :multipart => true }) do |f| -%>

Upload A File:
<%= f.file_field :uploaded_data %>

<%= submit_tag ‘Create’ %>

<% end -%>

14. Edit the index.html.erb file under the Uploads controller and add the following

File List
<% for fileMetaData in @fileMetaDatas -%>
<%= link_to fileMetaData.public_filename,fileMetaData.public_filename %></br>

<% end -%>

15. Edit the Routes and add this new route “map.upload_file ‘/new’, :controller => ‘upload’, :action => ‘create’“
16. Run migrations
17. And run the server, that’s it now you browse to http://localhost:3000/upload/new to upload a file.

I don’t have much server background, and probably its a lot easier to set up your servers with amazon EC2 than setting them up yourself or at other hosting solutions. I don’t care, it really annoys me that everybody claims how easy it is, showing you how to launch an instance in a minute. Yes, thats really easy, but you quit too abruptly. Nobody wants to set up an instance, then terminate it and lose everything you did on that instance. I say, never press terminate, you will lose every change from the last ami save. You are warned, be prepared or waste a lot of time.

Read on for links an tips for the whole cycle of launching, changing, saving and registering AMI. Everybody deploying to EC2 really have to do all this as a part of setting everything up, being prepared to launch more instances of the same kind.

If you launch an instance without knowing how to save and register AMIs, save yourself a lot of time (and a few pennies), by not doing a lot of work you might lose. If you do a lot of work, don’t press terminate, it’s not the same as a shutdown of your computer. You have to look at it as an ISO image of files, if you read it, work with the content, you’ll have to create a new ISO image to burn on your CD to keep the changes. At page 26 in the ElasticFox it says “Bundling a Linux/UNIX instance requires the use of the AMI tools”. OK, as you probably understand, I’m burn.

I am now successfully using both ec2-api-command-line-tools, elasticfox and amazons web console.

Ok, so what is the minimum need to get a small server running ubuntu and a mysql database?

• EC2 for your server and database
• S3 for storing your AMIs and register them
• EBS is optional, but you should set one up as a safety-net, replicating your data.
• both the ec2 and ami command line tools.

My links, tips and references.

The ec2 api command line tool:

• http://paulstamatiou.com/how-to-getting-started-with-amazon-ec2 EU? Important addition, put this in you bashrc or bash_profile too

export EC2_URL='https://eu-west-1.ec2.amazonaws.com/'

• AWSEC2 Command Line Reference

ElasticFox

• Amazon ElasticFox pdf tutorial
• If you’re using the alestic ubuntu images below, remember to change “SSH user” to ‘ubuntu’, from the Tools menu in ElasticFox (icon top-right)

EBS to replicate your data

• MySQL database server, including snapshot backup and restore.

Finding ubuntu EC2 AMIs:

• http://alestic.com/

SAVING AMIs

First, make sure you have a bucket in S3 for storing the your new ami. I use S3 Firefox Organizer

• I suppose you have launched an instance
• then partly follow this http://robrohan.com/2009/01/30/saving-a-customised-linux-amazon-instance-ec2-and-s3/
• with the exception if your using alestic ubuntu AMIs (they don’t use root, but user=ubuntu). Run this on your EC2 instance:

mirror=http://us.ec2.archive.ubuntu.com/ubuntu/
printf "%s\n%s\n" "deb ${mirror} karmic multiverse" \
"deb-src ${mirror} karmic main" |
sudo tee /etc/apt/sources.list.d/multiverse.list
sudo apt-get update && sudo apt-get install ec2-ami-tools

I struggled a lot with sudo, but found the solution mentioned above, at here at google groups

Now you should be all set to launch a new instance based on that new AMI of yours! Break a leg!

GUIDA PRATICA ALLA SCELTA DI UNA SCARPA ANTINFORTUNISTICA

SOMMARIO DELLA GUIDA :

PRIMA PARTE :  CONOSCERE LE CERTIFICAZIONI (dopo l’introduzione)

SECONDA PARTE : LE PARTI DI UNA SCARPA DI SICUREZZA

TERZA PARTE :  SCEGLIERE LA SCARPA DA UOMO

QUARTA PARTE :  SCEGLIERE LA SCARPA DA DONNA

INTRODUZIONE :

Dopo aver recensito decine e decine di scarpe antinfortunistiche, abbiamo pensato che tutta questa scelta può creare confusione o difficoltà nei nostri clienti. Il mercato in effetti offre tantissime alternative e, spesso, è facile sbagliare acquisto senza conoscere le caratteristiche tecniche e di sicurezza della scarpa che si stà acquistando.

Da qui, l’idea di questo articolo. Composto da quattro capitoli  sempre in aggiornamento dove riverseremo tutte le informazioni e i consigli per scegliere la scarpa da lavoro ideale

Inizieremo spiegando il significato delle certificazioni delle scarpe,  elemento fondamentale per conoscerle appieno. Quindi elencheremo ogni parte che compone la scarpa, come fosse l’analisi di un’automobile e spiegheremo tutti i materiali e le tecnologie applicate. Infine negli ultimi due blocchi entreremo nell’aspetto pratico e vi guideremo nella scelta della scarpa ideale per i vostri piedi, per uomo e per donna.

Da quando la sicurezza è legge nelle aziende, è aumentato il numero di settori che deve utilizzare le scarpe antinfortunistiche. In passato solo chi lavorava in cantiere ne faceva uso, ma oggi persino in bar ed alberghi c’è l’obbligo di indossarle.

CONOSCERE LE CERTIFICAZIONI

La certificazione minima richiesta è SB (S=Sicurezza, B=Base). Questa sigla attesta che la scarpa soddisfa i requisiti fondamentali della norma EN345 che richiede il PUNTALE D’ACCIAIO da 200 Joule.

Aggiungendo una suola antistatica con assorbimento di energia nella zona del tallone e sua relativa protezione, la scarpa sarà certificata S1.

Una scarpa S1 in pratica ha una protezione con puntale d’acciaio per le dita del piede ed una suola antistatica ma sprovvista di lamina antiperforazione.
In genere le scarpe S1 sono utilizzate da magazzinieri, operatori alberghieri, industria alimentare e tutti quei mestieri che non hanno rischi per la pianta del piede (tipici dei cantieri con chiodi a vista).

Restando su scarpe senza protezione alla pianta del piede, la certificazione S2, descrive una scarpa S1 dotata di tomaia in pelle o qualsiasi materiale impermeabile per un tempo maggiore di 60 minuti. Queste scarpe sono adatte per chi lavora a contatto con liquidi che verrebbero inevitabilmente assorbiti da scarpe S1 con pelli scamosciate. Solitamente le scarpe S2 hanno pelli in nabuk, fiore o anche scamosciate ma con un trattamento idrorepellente che le renda ugualmente impermeabili.

Elevando il livello di sicurezza, troviamo le classicissime scarpe S1P ed S3 che non sono altro delle scarpe S1 ed S2 dotate di lamina antiperforazione. Quest’ultima può essere realizzata in ACCIAIO o in KEVLAR (la cosidetta lamina in composito ovvero NON-METALLICA).

La certificazione S4 ed S5 determina scarpe impermeabili al 100% come stivali in gomma o scarpe con inserti in materiali sintetici che sono water resistant in qualsiasi condizione. La scarpa S5 ha in aggiunta la lamina antiperforazione, che troviamo negli stivali di sicurezza nei cantieri e nelle scarpe alte come la famosa STOP RAIN.

Il nostro articolo prosegue nella seconda parte dove esporremo tutte le tipologie di scarpe di sicurezza e le loro caratteristiche.

CLICCA SUL BANNER

]]> http://agilecat.wordpress.com/2009/11/14/amazon-%e3%81%ae-asia-%e5%ae%a3%e8%a8%80%e3%81%af-%e3%82%ab%e3%83%83%e3%82%b3%e3%82%a4%e3%82%a4%ef%bc%81/ Sat, 14 Nov 2009 00:39:43 +0000 Agile Cat http://agilecat.wordpress.com/2009/11/14/amazon-%e3%81%ae-asia-%e5%ae%a3%e8%a8%80%e3%81%af-%e3%82%ab%e3%83%83%e3%82%b3%e3%82%a4%e3%82%a4%ef%bc%81/ http://philemonworks.wordpress.com/2009/11/13/soek-goodies-st-exploring-open-source-smalltalk-libraries/ Fri, 13 Nov 2009 21:48:13 +0000 Ernest Micklei http://philemonworks.wordpress.com/2009/11/13/soek-goodies-st-exploring-open-source-smalltalk-libraries/

Soek is a Smalltalk application that provides a different way to navigate through documentation and source code of a Smalltalk library. Instead of the classic multi-list browser view in an image, Soek offers a flat view on all methods and classes and is build using the Seaside Web framework.

I discovered this way of publishing a framework when I worked with Rails and did most of my searches on Railsbrain.com. Not only I could easily find a particular class or method, it also showed me similar methods, other implementations, classes and their sources. The learning effect was great and it became my standard search tool and recommendation to others.

Wanting this for the Smalltalk community too, I started creating the application Soek in Cincom WebVelocity to have a similar view on libraries such as Seaside, Glorp, Cloudfork and even my own projects. I figured out how to parse the comment, declaration and body of a method, defined new syntax highlighting rules for Smalltalk and integrated the client-side search javascript functions from RailsBrian.com, kindly provided by Brian Chamberlain.

Because most libraries that I use are pretty stable, those documentation pages can very well be cached. So to make this happen, I developed a Publisher component that can generate all static pages to files creating a documentation set for each library. Next, I created a public Amazon S3 bucket to host all these documentation sets. Finally, I added a Launcher application as the front-end for this bucket to select which library documentation to explore. Available library information (name,version, s3-url,site-url) is accessed from a Amazon SimpleDB domain using Cloudfork ActiveItem.

The result is now available at soek.goodies.st

The Soek application is made open-source under MIT license and published in the Cincom WebVelocity Community.

S3 (St Benedicts) have been working towards finishing their investigation sheet of their expressive intermediate exam. The investigation sheet requires pupils to draw analytical studies of their chosen area; still life.

Peppers are often used as an introduction to still life drawing. This is because the pepper is an interesting natural shape, it’s surface is shiny, it’s insides are filled with detail and crevices, it is colourful and varied. The Pepper is the perfect object to learn observations skills from.

Below Robert shows good use of contrast, he has a great personal style to his drawing, it is free and scribbled. It has character and with practice, Robert should be able to fine tune his scribbles to get a controlled, stylised style.

Above Antonia adds more detail and tone to her flower study. She uses cross-hatching to add darker tones, as well as hatching to the contours of the petals to give her drawing form and substance. While below Heather uses her clean and patient tonal skills to bring volume to her Pepper.

Below Robyn works her scratchy style into her pepper. It is such a great expressive style that will also be useful when using pastels or paints, her use of multiple lines to cover the surfaces of her objects helps draw the viewers eye into the object. It’s like staring into the framework of how the objects are made.

And finally, above, Edward uses a similar style to help raise his flat objects from the page. By shading along the contours of an object, you can help to show the viewer the form and dimensions of the object. It’s a simple trick, though it has helped Edward make his pepper more realistic and make his drawing more interesting to to look at.

LAMPIRAN : PENGUMUMAN PENERIMAAN CPNSD PELAMAR UMUM DILINGKUNGAN
PEMERINTAH KOTA JAMBI FORMASI TAHUN 2009
NOMOR : 810/ 1566/BKD
TANGGAL : 28 OKTOBER 2009
TENTANG : RINCIAN FORMASI PEGAWAI NEGERI SIPIL DAERAH
KOTA JAMBI TAHUN ANGGARAN 2009
NO JABATAN KUALIFIKASI PENDIDIKAN KEBUTUHAN
1 2 3 5
I TENAGA GURU
A GURU SD
1 Guru Kelas S.1 PGSD 15
D.II PGSD 30
2 Guru Penjaskes S.1 Pendidikan Olah Raga Kesehatan 7
3 Guru Agama Islam S.1 Pendidikan Agama Islam 15
JUMLAH GURU SD 67
B GURU SMP
1 Guru Teknologi Informatika Komputer S.1 Pendidikan Komputer 5
2 Guru Penjaskes S.1 Pendidikan Jasmani dan Kesehatan 2
3 Guru Seni S.1 Pendidikan Kesenian 2
4 Guru Bimbingan Konseling S.1 Pendidikan Bimbingan dan Konseling 6
5 Guru Fisika S.1 Penddidikan Fisika 3
6 Guru Bahasa Inggris S.1 Pendidikan Bahasa Inggris 4
7 Guru Geografi S.1 Pendidikan Geografi 2
8 Guru Agama Islam S.1 Pendidikan Agama Islam 7
9 Guru Sejarah S.1 Pendidikan Sejarah 2
10 Guru Agama Kristen S.1 Pendidikan Agama Kristen 1
11 Guru PPKN S.1 PPKN 2
12 Guru Matematika S.1 Pendidikan Matematika 5
13 Guru Biologi S.1 Pendidikan Biologi 3
JUMLAH GURU SMP 44

1 2 3 5
B GURU SMA
1 Guru Teknologi Informatika Komputer S.1 Pendidikan Komputer 2
2 Guru Seni S.1 Pendidikan Kesenian 1
3 Guru Penjaskes S.1 Pendidikan Jasmani dan Kesehatan 2
4 Guru Sejarah S.1 Pendidikan Sejarah 2
5 Guru Bimbingan Konseling S.1 Pendidikan Bimbingan dan Konseling 3
6 Guru Bahasa Jerman S.1 Pendidikan Bahasa Jerman 2
7 Guru Bahasa Inggris S.1 Pendidikan. Bahasa Inggris 2
8 Guru Geografi S.1 Pendidikan Geografi 2
9 Guru Sosiologi S.1 Pendidikan Sosiologi 2
10 Guru Agama Islam S.1 Pendidikan Agama Islam 4
11 Guru Fisika S.1 Pendidikan Fisika 2
12 Guru PPKN S.1 PPKN 1
13 Guru Bahasa Jepang S.1 Pendidikan. Bahasa Jepang 1
14 Guru Matematika S.1 Pendidikan Matematika 3
15 Guru Kimia S.1 Pendidikan Kimia 2
16 Guru Biologi S.1 Pendidikan Biologi 2
17 Guru Akuntansi S.1 Pendidikan Akuntansi 2
JUMLAH GURU SMA 35
C SMK N
1 Guru Matematika S.1 Pendidikan Matematika 2
2 Guru Fisika S.1 Pendidikan Fisika 1
3 Guru Bahasa Jepang S.1 Pendidikan Bahasa Jepang 1
4 Guru Teknik Komputer S.1 Pendidikan Komputer 1
5 Guru Pariwisata S.1 Pendidikan Usaha Jasa Pariwisata 1
6 Guru Bahasa Inggris S.1 Pendidikan Bahasa Inggris 1
7 Guru Bimbingan Konseling S.1 Pendidikan Bimbingan dan Konseling 1
8 Guru Perkantoran S.1 Pendidika Adm. Perkantoran 1
9 Guru Biologi S.1 Pendidikan Biologi 1
10 Guru Akuntansi S.1 Pendidikan Akuntansi 1
JUMLAH GURU SMK 11
JUMLAH TENAGA GURU 157
II TENAGA KESEHATAN
1 Dokter Umum Dokter 15
2 Dokter Gigi Dokter Gigi 5
3 Dokter Spesialis Dokter Spesialis Bedah 1
Dokter Spesialis Patologi Klinis 1
Dokter Radiologi 1
Dokter Penyakit Dalam 1
Dokter Obstetri/Ginekolog 1
4 Fisioterapi S.1 Physioterapi 1
5 Nutrisionis S.1 Gizi 2
D.III Gizi 4
6 Perawat D.III Perawat 20
7 Radiografer D.III Penata Rontgen 2
8 Asisten Apoteker D.III Farmasi 4
SMF 3
9 Sanitarian D.III Analis Kesehatan 4
S.1 Kesehatan Masyarakat 2
DIII Kesehatan Gizi 2
D.III Kesehatan Lingkungan 1
D.III Penilik Kesehatan 1
Sekolah Pembantu Penilik Higiene 1
10 Bidan D.III Kebidanan 6
11 Perawat Sekolah Perawat Kesehatan 2
12 Perawat Gigi Sekolah Perawat Gigi 2
13 Pranata Laboratorium Kesehatan SMAK 2
JUMLAH TENAGA KESEHATAN 84

1 2 3 5
III TENAGA TEKNIS
1 Medik Veteriner Dokter Hewan 2
2 Penyuluh Pertanian S.1 Pertanian 4
3 Pengawas Perikanan S.1 Perikanan 3
4 Pengawas Bibit Ternak S.1 Peternakan 2
5 Penjamin Mutu Pakan S.1 Peternakan 2
6 Pengawas Teknis Tata Bangunan dan Perum. S.1 Teknik Sipil 4
S.1 Arsitektur 2
7 Penata Ruang S.1 Planologi 2
8 Perencana S.1 Geologi 1
S.1 Teknik Pertambangan 1
S.1 Ilmu Sosial dan Politik 1
9 Surveyor Pemetaan S.1 Giodesi 2
10 Analisis Perekonomian S.1 Ekonomi Pembangunan 2
11 Pengawas Teknis Jalan dan Jembatan S.1 Teknik Sipil 3
12 Pengendali Dampak Lingkungan S.1 Teknik Lingkungan 2
13 Auditor S.1 Teknik Sipil 1
14 Penyuluh Perindag S.1 Teknik Industri 2
15 Pengawas Teknisi Mesin S.1 Teknik Mesin 2
16 Pengawas Teknis Kelistrikan S.1 Teknik Elektro 1
17 Pranata Komputer S.1 Komputer 5
S.1 Teknik Komputer 1
S.1 Teknik Komputer 1
D. III Komputer 6
18 Pranata Humas S.1 Ilmu Komunikasi 2
S.1 Flm 1
19 Perancang Perundang-Undangan S.1 Ilmu Hukum 5
S.1 Sarjana Hukum Islam 3
20 Pengawas Ketenagakerjaan S.1 Ilmu Hukum 3
21 Penata Laporan Keuangan S.1 Ekomomi Akuntansi 7
22 Verifikator Keuangan D. III Akutansi 12
23 Penyusun Program dan Evaluasi S.1 Ekonomi Pembangunan 4
S.1 Ekonomi Manajemen 2
24 Pustakawan S.1 Perpustakaan 1
25 Arsiparis S.1 Ekonomi Manajemen 2
D.III Administrasi 6
26 Psikologi Klinis S.1 Pisikologi Sertifikat Profesi 2
27 Analisi Kepegawaian S.1 Psikologi 1
28 Penyuluh Agama S.1 Ushuludin Bimbingan Penyuluh Agama Isla 1
S.1 Syariah jurusan Ahwalus Syahsiah 2
29 Penyuluh KB S.1 Kesehatan Masyarakat 4
30 Perencana Pengembangan Kepariwisataan S.1 Pariwisata 1
S.1 Bahasa Inggris 1
31 Pamong Budaya S.1 Seni Musik 1
S.1 Seni Tari 1
32 Penyuluh Sosial S.1 Kesejahteraan Sosial 1
D.III Kesejahteraan Sosial (Tata Rias) 1
33 Pemandu Wisata D.III Pariwisata 2
34 Penata Laporan Keuangan S.1 Akuntansi 6
35 Verifikator Keuangan D. III Akutansi 3
36 Pengawas Keselamatan Transportasi D.III Transportasi 5
37 Analis Tata Praja S.1 Ilmu Sosial dan Politik 1
38 Analis Kesbangpolinmas S.1 Ilmu Sosial dan Politik 2
39 Penyuluh Koperasi S.1 Ekonomi Manajemen 2
40 Pembinaan Mental S.1 Ushuludin Bimbingan Penyuluh Agama Isla 1

JUMLAH TENAGA TEKNIS 138
TOTAL 379

“To prepare educators who demonstrate a positive impact on student learning”

L: KNOWLEDGE OF LEARNERS AND THEIR DEVELOPMENT IN SOCIAL CONTEXTS

     L1: Learner Centered (a variety of culturally responsive, developmentally and age appropriate strategies)

     L2: Classroom/School Centered (learning, knowledge and skills connected to classroom and school communities)

     L3: Family/Neighborhood Centered (informed by collaboration with families and neighborhoods)

     L4: Contextual Community Centered (responsible citizenship for an environmentally sustainable, globally interconnected and diverse society)

P: UNDERSTANDING OF TEACHING AS A PROFESSION

     P1: Informed by Professional Responsibilities and Policies (a collegial and professional school setting)

     P2: Enhanced by Reflective, Collabroative, Professional Growth-Centered Practice (benefiting students)

     P3: Informed by Legal and Ethical Responsibilities (students benefit from a safe and respectful learning environment)

S: SUBJECT MATTER AND CURRICULUM GOALS

     S1: Content Driven (use of reading, written and oral communication and technology)

     S2: Aligned with Curriculum Standards and Outcomes (student learning targets and progress to meet them)

     S3: Integrated Across Content Areas (subject matter integrating mathematical, scientific and aesthetic reasoning)

T: KNOWLEDGE OF TEACHING

     T1: Informed by Standards-Based Assessment (analysis using formative, summative and self-assessment)

     T2: Intentionally Planned (beneficial standards-based plannning that is personalized)

     T3: Influenced by Multiple Instructional Strategies (addressing ability levels and cultural backgrounds)

     T4: Informed by Technology (designed to create technologically proficient learners)

En Voota creemos que cada uno debe dedicarse a lo que mejor sabe hacer. Por eso, desde el primer momento, no quisimos encargarnos de comprar, instalar y configurar servidores. Amazon Web Services (AWS) ofrece un sistema de virtualización que nos abstrae de gran parte de este trabajo de sistemas. De momento empezaremos utilizando 2 de sus servicios:

• EC2: Amazon Elastic Cloud Computing
• S3: Amazon Simple Storage Service

Así utilizamos EC2

Este es, sin duda, el núcleo de los servicios de virtualización. Permite crear servidores web, servidores de bases de datos y … servidores en general. El concepto es simple: Permite crear todos los servidores que necesite el proyecto desde una interfaz web. Por supuesto son servidores virtuales, pero a todos los efectos es igual que tener un servidor en el despacho de abajo, con la ventaja de que puedes incrementar el número de servidores con un clic de ratón.

Lista de instancias en Amazon EC2

Las instancias en EC2 son servidores en ejecución. Se paga por el uso de instancias, lo cual permite tener más o menos servidores sirviendo páginas en función del tráfico del sitio en cada momento.

Otro concepto muy interesante es del AMI (Amazon Machine Image) que no es otra cosa que un servidor “congelado” o, más técnicamente, una imagen de servidor. Cuando se necesita arrancar una nueva instancia, se abre la “nevera” y se le dice a Amazon: “Arráncame uno de estos” y se crea una instancia nueva.

Elegir un AMI

Cualquiera en la comunidad puede crear sus propias imágenes al igual que cualquier distribuidor de software. En el caso de Voota, utilizamos Ubuntu server. Canonical nos lo pone fácil y pone a disposición de cualquier usuario de EC2 su “servidor congelado”. Ya está disponible en Karmic Koala (la nueva versión de ubuntu).

Pero esto es sólo para la primera vez. En Voota, una vez que tuvimos el servidor instalado con el software necesario y listo para servir páginas, le hicimos una foto. Es decir, lo congelamos a un AMI. De esta forma, la próxima vez que sea necesario arrancar una nueva instancia, lo haremos desde nuestro propio AMI, que ya está listo para funcionar.

AMI del servidor web de Voota

Así utilizamos S3

S3 es un servicio de almacenamiento. Permite almacenar cualquier tipo de información mediante ficheros (imágenes, vídeos, AMIs, backups, etc.). Para nosotros es muy útil a la hora de almacenar las imágenes y los vídeos. Un error muy común en el desarrollo web es almacenar estos ficheros multimedia en un disco del servidor. Todo funciona bien hasta que se necesitan más servidores y por tanto compartir estos ficheros de imágenes. Hay varias soluciones para este problema:

• Sincronizar continuamente los ficheros entre todos los servidores. Bastante poco práctico sobre todo a medida que va creciendo la estructura.
• Utilizar una unidad compartida de modo que todos los servidores lean y escriban en el mismo disco. Más cómodo pero se corre el peligro de saturar el disco con lo  cual el balanceo de los servidores no servirá para nada.
• Crear un servidor de ficheros al que todos los servidores web envíen los ficheros cuando hay que “escribir”. Y que sea este servidor de ficheros el encargado de servirlas directamente al navegador del usuario del sitio web.

Esto último es lo que nos ofrece S3. Cuando algún usuario de Voota carga una fotografía, ésta se envía directamente a S3, quien la almacena. Cuando esta fotografía ha de aparecer en alguna página web, será S3 el encargado de servirla.

Foto de Zapatero almacenada en S3

Esta foto está almacenada en http://imagesvoota.s3.amazonaws.com/politicos/bw_p_238.jpg

Otra utilidad de S3 es el almacenaje de los AMIs o “servidores congelados” que mencionaba antes. Para poder utilizar un AMI en EC2 es obligatorio tenerlo almacenado en S3.

Silverlight apps are nothing more than big zip files and Amazon S3 is dirt cheap and hyper-scalable. Why would you ever host your Silverlight .xap files on your own server or ISP? … especially with Silverlight Streaming being dropped soon.

Here’s a quick guide to putting your Silverlight apps on Amazon S3 and depending on your app, never worry about scalability or bandwidth costs again…

1) Create your Amazon S3 account.

2) Install S3 Organizer FireFox plugin (this is the equivelent of an FTP client for Amazon S3).

3) Run S3 Organizer, log into your account and create your bucket.

4) Upload your xap file to your bucket. BUT… you must add custom headers unless you are also going to host your .html file there too. Silverlight xaps need a MIME type specified when they are loaded from another domain. The good news is, this is easy with S3 as long as you do it at the time that you upload the file. There is probably a way to set it after the fact but not with S3 Organizer.

Simply set the content type to ‘application/x-silverlight-app’ and send up your xap. Don’t forget to do this EVERY time you upload an update.

5) After uploading your .xap file, set permissions so everyone can read your xap file. Right click on your newly uploaded xap file and choose “Edit ACL…”. Then check Read access for Everyone and Authenticated Users. You do NOT need to do this every time as S3 remembers your ACL settings.

6) Add the enableHtmlAccess param to your object tag within your html file to enable access to the DOM bridge (assuming your Silverlight app needs access to the DOM bridge).

For example:

7) Change your html page to load your xap file from S3 directly by setting the source param in your object tag.

For example:

Note: ‘mybucket’ is the name of your bucket on S3.

8 ) Upload your html (or aspx) page to your web server. GoDaddy.com offers cheap hosting for only $5 per month.

That’s it! At this point, the only scalability concerns you should have are those of your web services (assuming you call web services from your Silverlight app).

And with S3, the costs depend on the usage — which will literally cost you just pennies per month until you have some descent traffic. Do the math and you’ll see that it would only cost 17 cents to have a  300K .xap get hit 3500 times. At that rate you’d pay ~$48 to have 1 million new users per month. (I say “new” users because unless you update your xap, users should be caching your xap file and won’t need to re-download it).

Happy cheap hosting and Silverlight coding!

After trying to use Amazon’s S3 web service to backup files and to get a reliable download area for R functions and stuff which is not allowed to be uploaded to wordpress.com I ended up with some experimental “buckets” (= S3 online directory) and some 100 MB of files in them.

It turned out that it is not possible to delete a non-empty bucket from S3, so one is to required to recurse into the directories and delete all files one by one!

Eric Cheng and other blogs appearing after a google search pointed out S3sync as a suitable tool to remove a non-empty bucket.

So first one has to get Ruby and then also the OpenSSL interface for Ruby: sudo aptitude install ruby libopenssl-ruby

Then download s3sync (to your /home/yourself folder in this case) and unpack it: cd $HOME/
wget http://s3.amazonaws.com/ServEdge_pub/s3sync/s3sync.tar.gz tar xvzf s3sync.tar.gz
rm s3sync.tar.gz
This creates a s3sync folder containing the ruby code.

The package ca-certificates includes PEM files of CA certificates to allow SSL-based applications to check for the authenticity of SSL connections. It is needed to have the S3 connection secure via SSL and part of the default Ubuntu installation (at least included in my Xubuntu Karmic Koala. If not: sudo aptitude install ca-certificates

Before using s3sync get your access key and secret access key from Amazon. It has to be included in a file “s3config.yml” which is located in your home folder inside the directory “.s3conf” which has to be created. So:

mkdir $HOME/.s3conf
to create the directory.

Open your favorite text editor and create a plain textfile called s3config.yml inside the “.s3conf” folder which contains: aws_access_key_id: YourS3AccessKeyFromAmazon
aws_secret_access_key: YourS3SecretAccessKeyFromAmazon
SSL_CERT_DIR: /etc/ssl/certs

Prevent others from reading the configuration file containing your confidential access codes by chmod 700 $HOME/.s3conf/s3config.yml

Now you can start to use s3sync and s3cmd to manipulate your S3 storage space with e.g.: ruby $HOME/s3cmd.rb listbuckets

This was the first time I managed to manipulate successfully my S3 account. Ok, Djungledisk under Mac OS-X worked, but it is proprietary, though not expensive.

John Eberly’s blog was an inspiration to get started. Follow the link to his excellent blog post.

On Friday I grabbed lunch with Geoff Tudor, SVP of business development and co-founder of Nirvanix .  After they cleared the plates I talked to Geoff about what Nirvanix does and where he saw cloud storage heading.

Some of the topics Geoff tackles:

• Providing cloud storage for the enterprise from five data centers around the world that are pooled and presented as one large global file server.
• The Nirvanix “secret sauce”: the file virtualization layer that sits on top of pooled/virtualized commodity storage.
• How Nirvanix’s offering is different than Amazon’s S3 (hint: one’s targeted at enterprises and one’s targeted at developers)
• Customers such as the NASA/ASU library which is the largest cloud storage use ever and stores images from the Lunar Reconnaissance Orbiter camera.
• Security and how Nirvanix addresses customer’s concerns.
• What Geoff sees in the future for cloud storage.

Pau for now…

“Thomas Myer puts Amazon S3 to work as a simple, inexpensive, efficient backup solution for small businesses.”  Click here to read.