Κυριακή, 16 Ιανουαρίου 2011

Amazon Cloud Free Usage Tier

To help new AWS customers get started in the cloud, AWS is introducing a new free usage tier. Beginning November 1, new AWS customers will be able to run a free Amazon EC2 Micro Instance for a year, while also leveraging a new free usage tier for Amazon S3, Amazon Elastic Block Store, Amazon Elastic Load Balancing, and AWS data transfer. AWS’s free usage tier can be used for anything you want to run in the cloud: launch new applications, test existing applications in the cloud, or simply gain hands-on experience with AWS.


For more information visit http://aws.amazon.com/free/

But be careful because Amazon Elastic IP assigned to Amazon Ec2 virtual image is not free. So watch daily your account activity in order to be prepared of what you will have to pay. Thats the reason why you should provide your credit card information for the amazon free tier.


M.P.

Τρίτη, 11 Ιανουαρίου 2011

M/DB:X - Lightweight Native XML Cloud Database

This is a brand new concept: an XML Database that's simple and easy to use, entirely accessed via HTTP/REST, and ready for use in the Cloud. There's nothing else like it out there, and it's ready to turn the whole idea of handling and storing XML on its head!
It's called M/DB:X, it's already released and it's ready for use. You can get all the details at http://www.mgateway.com/mdbx.html.
So what, in a nutshell, is M/DB:X?

It's an XML database for the Cloud.

What does that mean?

Well, it's a set of REST services that allow you to create and manipulate persistent XML Document Object Models (DOM). You can import XML Documents either as a stream of XML that you send to it in a REST request, or you can ask M/DB:X to fetch a file over the Internet, perhaps from an Amazon S3 bucket.
Alternatively you can build a DOM from scratch, starting with an empty shell containing just a single tag to which you add new tags using simple REST requests.

So what? It can store XML? What's the big deal?

Well, once a DOM is created in M/DB:X you can:
  • Display it using the outputDOM Action. The XML document is returned in the HTTP response
  • Search the contents of the document using XPath queries
  • Inspect the properties of its nodes
  • Modify the properties of its nodes
  • Add new nodes
  • Remove existing nodes
  • Transform a document in any way you like using a combination of the above
  • And, of course, finally delete the document
..all using simple REST requests.
There are, of course, Native XML Database out there already, but what differentiates M/DB:X is two key things:
- its simplicity. M/DB:X disposes of most of the formality and complexity normally associated with handling XML
- you access it using HTTP/REST requests and it returns its responses as XML.

Basically it's like Amazon SimpleDB meets XML in the Cloud!
All the other Native XML Databases are heavyweight and very formal affairs, built around the concept of XML being validated against a schema and with rigorous adherence to XML namespacing rules.
M/DB:X throws all that away and takes the "good enough" approach, simplifying the concept right
down. Much as SimpleDB provides a place where you can throw together spreadsheet-like databases without any need for pre-defining a schema or indexes, M/DB:X allows you to quickly and easily throw together XML documents and play around with them in any way you like.

M/DB:X also bucks the trend by using a non-validating parser. Basically you can throw anything that looks vaguely like XML at M/DB:X and it will do its best to turn it into an XML DOM. It won't return errors and it won't complain that what you gave it doesn't conform to a particular schema or that it wasn't properly structured XML. If it can turn it into a DOM, it will.

This will have the XML gurus out there wailing and gnashing their teeth of course! So why's this a cool thing and not a problem?

Well, for example, it means that you can get it to import "lazy" structured HTML pages from any URL you like and it will tidy it up as best it can and turn it into an XML DOM for you. Once it's done that for you, you can analyse that page, take bits out of it, find stuff in it, all using proper XML techniques and XPath queries instead of hacking about with the raw page text.

Relax, however: give M/DB:X a properly structured valid XML document and it will produce the DOM you'd expect!
Speed, simplicity, ease of operation and near-zero administration are the objectives of M/DB:X.
It's a simple-to-install extension to the M/DB Virtual Appliance, so you can be up and running in no time at all.
XML databases just got simple! Go and check it out!
Oh, and did I mention: M/DB:X is free Open Source software.


Σάββατο, 8 Ιανουαρίου 2011

Amazon S3 and BPEL

As Amazon cloud offers web services interfaces to access its resources, it is possible to call amazon web services from a BPEL process. Here is a simple example of a BPEL process that calls the Amazon S3 ListAllMyBuckets operation. In order to be able to test this BPEL process you should have an Amazon account and to subscribe for Amazon S3. Then, you should use openssl as described in an older post (http://softwaretechnologiesblog.blogspot.com/2010/12/soapui-and-amazon-s3.html) in order to generate a signature based on amazon public key in order to execute BPEL process and invoke the AmazonS3 operation.

At this BPEL process two assign activites are used and one Invoke activity.

The BPEL file AmazonBPEL.bpel can be found here


https://docs.google.com/document/pub?id=1rYZq-vOTxg8C3yRKJ1yaCu6_EKB_6FK2owawoOJTJgk

and the AmazonBPELArtifacts.wsdl can be found here

https://docs.google.com/document/pub?id=1NKCpRF9D8UV9IB6-LLvpATcX29Ul978BDS45zP6fCtw

This BPEL process was created using eclipse designor and the BPEL plugin.In order to execute the BPEL process you should download a server like Apache Ode and configure it on eclipse.


M.P.

Πέμπτη, 6 Ιανουαρίου 2011

Τετάρτη, 5 Ιανουαρίου 2011

Amazon SQS sample java file

The SimpleQueueServiceSample.java file is a sample java file for accessing the following SQS operations

  • createQueue
  • listQueues
  • sendMessage
  • receiveMessage
  • deleteMessage
  • deleteQueue
SimpleQueueServiceSample.java can be viewed here


https://docs.google.com/document/pub?id=1CEHTnyziGiVicf0mLkcjOweDa2ZrLEd5UeNauEB_60k



copy and paste the code into a file named SimpleQueueServiceSample.java under a package named amazonpack.

In order to run the SampleS3 java class you should include in your classpath the following jars

aws-java-sdk-1.1.1.jar
aws-java-sdk-1.1.1-javadoc.jar
aws-java-sdk-1.1.1-sources.jar
commons-codec-1.3.jar
commons-discovery-0.2.jar
commons-httpclient-3.0.1.jar
commons-logging.jar
commons-logging-1.1.1.jar

These can be found on AWS SDK for Java that can be downloaded from here

http://aws.amazon.com/eclipse/

Amazon S3 sample java file

The SampleS3.java file is a sample java file for accessing the following S3 operations

  • createBucket
  • putObject
  • getObject
  • listObjects
  • deleteObject
  • deleteBucket
SampleS3.java can be viewed here


https://docs.google.com/document/pub?id=1D9nPJKkYsiykVsvOTGGHJTXa2a-KmXCOYCa0kRUxxIc



copy and paste the code into a file named SampleS3.java under a package named amazonpack.

In order to run the SampleS3 java class you should include in your classpath the following jars

aws-java-sdk-1.1.1.jar
aws-java-sdk-1.1.1-javadoc.jar
aws-java-sdk-1.1.1-sources.jar
commons-codec-1.3.jar
commons-discovery-0.2.jar
commons-httpclient-3.0.1.jar
commons-logging.jar
commons-logging-1.1.1.jar

jackson-core-asl-1.4.3.jar
jaxrpc.jar

These can be found on AWS SDK for Java that can be downloaded from here

http://aws.amazon.com/eclipse/

Τρίτη, 4 Ιανουαρίου 2011

AWS Toolkit for Eclipse and Amazon S3

If you want a java sample for calling Amazon S3 basic operations line createBucket, ListBucket, putObject etc you can use the AWS Toolkit for Eclipse, an open source plug-in for the Eclipse Java IDE that makes it easier for developers to develop, debug, and deploy Java applications using Amazon Web Services. With the AWS Toolkit for Eclipse, you’ll be able to get started faster and be more productive when building AWS applications.
The AWS Toolkit for Eclipse features:

* AWS SDK for Java
* Amazon SimpleDB Management
* Amazon EC2 Management

Download and install the AWS Toolkit for Eclipse using the following Eclipse Update Site:

http://aws.amazon.com/eclipse/

To install on Eclipse 3.5 or higher

1. Open Help -> Install New Software….
2. Enter http://aws.amazon.com/eclipse in the text box labeled “Work with” at the top of the dialog.
3. Select “AWS Toolkit for Eclipse” from the list below.
4. Click “Next”. Eclipse guides you through the remaining installation steps.

For more information visit http://aws.amazon.com/eclipse/