Ready, Set, Go - Getting started with Tuscany

Install the Tuscany Eclipse Plugin

The first thing you do is to start Eclipse and go to Help -> Software Updates -> Find and Install,
select "Search for new features to install" and then click next

On the next dialog, click on "New Remote Site..." to create a new site entry. Give it a name such as
"Tuscany" and add the site URL as *http://people.apache.org/~jsdelfino/tuscany/tools/updatesite/*

Make sure the "Remote Site" that was just created is selected, and click "Finish"

Select the "Apache Tuscany SCA Tools" and click "Next", and then, on the next dialog, click "Finish"

Accept the "Plugin License"

and next click on "Install All"

When asked to "restart eclipse", click the "yes" button.

Create your 1st Composite Service Application

The following shows the composition diagram for the composite service application you are about
to create.

The composite service application you will create is a composition of four services. The composed
service provided is that of an on-line store.
There is a Catalog service which you can ask for catalog items, and depending on its currency
code property configuration it will provide the item prices in USD or EUR. The Catalog service is not
doing the currency conversion itself it references a CurrencyConverter service to do that task. Then
there is the ShoppingCart service into which items chosen from the catalog can be added, it is
implemented as a REST service. The Catalog is bound using the JSONRPC binding, and the
ShoppingCart service is bound using the ATOM binding. Finally there is the Store user facing
service that provides the browser based user interface of the store. The Store service makes use of
the Catalog and ShoppingCart service using the JSONRPC, and ATOM binding respectively.

Create a Java Project

In this step you create a Java Project in Eclipse to hold the composite service application.
Click on the New Java Project button in the toolbar to launch the project creation dialog.
Next you enter "store" as the Project name, and for Project Layout select Create separate
folders for sources and class files.

Hit the Next button, and on the following page go to the Libraries tab. Use the Add Library...
button on the right to add the Tuscany Library library to the project.

Hit the Finish button to complete the New Java Project dialog to create the "store" java project.

Construct Services

First you create two package folders into which later in this step you place service implementations.
Select the "store" project and click on the New Java Package button in the toolbar to launch
the package creation dialog.

Next you enter "services" as the package Name, and press the Finish button to complete the
dialog.

Repeat the previous step to create another package named "ufservices". The store project now
should look as follows.

In the following you will place in the "services" package the regular services, and in the "ufservices"
package the user facing services of the composite service application you create.

Catalog

In this step you create the Catalog service interface and implementation.
Select the "services" package. Next you click on the dropdown arrow next to the New Java Class
button and select the New Java Interface option from the dropdown list. In the dialog
enter "Catalog" as the Name of the interface and select the Finish button to complete the dialog.
The Java editor will open on the new created Java interface. Replace the content of the editor by
copy-paste of the following Java interface code snippet.

package services;
import org.osoa.sca.annotations.Remotable;
@Remotable
public interface Catalog {
    String[] get();
}

Select the "services" package again. Select the New Java Class button . In the dialog enter
"CatalogImpl" as the Name of the class, add "Catalog" as the interface this class implements, and
then select Finish to complete the dialog.

The Java editor will open on the new created Java class. Replace the content of the editor by
copy-paste of the following Java class code snippet.

package services;
import java.util.ArrayList;
import java.util.List;
import org.osoa.sca.annotations.Init;
import org.osoa.sca.annotations.Property;
import org.osoa.sca.annotations.Reference;
public class CatalogImpl implements Catalog {
	@Property
	public String currencyCode = "USD";
	@Reference
	public CurrencyConverter currencyConverter;
	private List<String> catalog = new ArrayList<String>();
	@Init
	public void init() {
		String currencySymbol = currencyConverter.getCurrencySymbol(currencyCode);
		catalog.add("Apple - " + currencySymbol +
		currencyConverter.getConversion("USD", currencyCode, 2.99f));
		catalog.add("Orange - " + currencySymbol +
		currencyConverter.getConversion("USD", currencyCode, 3.55f));
		catalog.add("Pear - " + currencySymbol +
		currencyConverter.getConversion("USD", currencyCode, 1.55f));
	}
	public String[] get() {
		String[] catalogArray = new String[catalog.size()];
		catalog.toArray(catalogArray);
		return catalogArray;
	}
}

After completing these steps the content of the "store" project will look as follows.

Note: CatalogImpl is red x'ed because it makes use of the CurrencyConverter interface that we
have not implemented yet.

CurrencyConverter

In this step you create the CurrencyConverter service interface and implementation.
You follow the same steps that you learned previously to create the interface and implementation.
First create a Java interface in the "services" package named "CurrencyConverter" and copy-paste
the following Java interface code snippet into it.

package services;
import org.osoa.sca.annotations.Remotable;
@Remotable
public interface CurrencyConverter {
	public float getConversion(String fromCurrenycCode,
	String toCurrencyCode, float amount);
	public String getCurrencySymbol(String currencyCode);
}

Next create a Java class in the "services" package named "CurrencyConverterImpl" and copy-paste
the following Java class code snippet into it.

package services;
public class CurrencyConverterImpl implements CurrencyConverter {
	public float getConversion(String fromCurrencyCode,
		String toCurrencyCode, float amount) {
		if (toCurrencyCode.equals("USD"))
			return amount;
		else 			if (toCurrencyCode.equals("EUR"))
				return amount*0.7256f;
		return 0;
	}
	public String getCurrencySymbol(String currencyCode) {
		if (currencyCode.equals("USD"))
			return "$";
		else
			if (currencyCode.equals("EUR"))
				return "€";
		return "?";
	}
}

After completing these steps the content of the "store" project will look as follows.

ShoppingCart

In this step you create the ShoppingCart service implementation.

You follow the same steps that you learned previously to create the implementation.

Create a Java class in the "services" package named "ShoppingCartImpl" and copy-paste the
following Java class code snippet into it.

package services;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.UUID;
import org.apache.tuscany.sca.binding.feed.collection.Collection;
import org.apache.tuscany.sca.binding.feed.collection.NotFoundException;
import com.sun.syndication.feed.atom.Content;
import com.sun.syndication.feed.atom.Entry;
import com.sun.syndication.feed.atom.Feed;
import com.sun.syndication.feed.atom.Link;
public class ShoppingCartImpl implements Collection {
	// needs to change to instance var once conversation scope works
	private static Map<String, Entry> cart = new HashMap<String, Entry>();
	public Feed getFeed() {
		Feed feed = new Feed();
		feed.setTitle("shopping cart");
		Content subtitle = new Content();
		subtitle.setValue("Total : " + getTotal());
		feed.setSubtitle(subtitle);
		feed.getEntries().addAll(cart.values());
		return feed;
	}
	public Entry get(String id) throws NotFoundException {
		return cart.get(id);
	}
	public Entry post(Entry entry) {
		String id = "cart-" + UUID.randomUUID().toString();
		entry.setId(id);
		Link link = new Link();
		link.setRel("edit");
		link.setHref("" + id);
		entry.getOtherLinks().add(link);
		link = new Link();
		link.setRel("alternate");
		link.setHref("" + id);
		entry.getAlternateLinks().add(link);
		entry.setCreated(new Date());
		cart.put(id, entry);
		return entry;
	}
		public void put(String id, Entry entry) throws NotFoundException {
		entry.setUpdated(new Date());
		cart.put(id, entry);
	}
	public void delete(String id) throws NotFoundException {
		if (id.equals(""))
			cart.clear();
		else
			cart.remove(id);
	} 	private String getTotal() {
		float total = 0;
		String symbol = "";
		if (!cart.isEmpty()) {
			Entry entry = cart.values().iterator().next();
			String item = ((Content)entry.getContents().get(0)).getValue();
			symbol = item.substring(item.indexOf("-")+2, item.indexOf("-")+3);
		}
		for (Entry entry : cart.values()) {
			String item = ((Content)entry.getContents().get(0)).getValue();
			total += Float.valueOf(item.substring(item.indexOf("-")+3));
		}
		return symbol + String.valueOf(total);
	}
}

Note: Since the Tuscany conversational support is not ready yet the cart is realized through a hack.
The cart field is defined as static.

After completing these steps the content of the "store" project will look as follows.

Store

In this step you create the user facing Store service that will run in a Web browser and provide the
user interface to the other services you created.

Select the "ufservices" package. Right click to get the context menu, select New, and then File. In
the New File dialog enter "store.html" for the File name, and then select Finish to complete the
dialog.

The Text editor will open on the new created html file. Replace the content of the editor by copy-paste
of the following html snippet.

<html>
<head>
<title>Store</TITLE>

<script type="text/javascript" src="store.js"></script>

<script language="JavaScript">

	//@Reference
	var catalog = new Reference("catalog");

	//@Reference
	var shoppingCart = new Reference("shoppingCart");


	function catalog_getResponse(items) {
		var catalog = "";
		for (var i=0; i<items.length; i++)
			catalog += '<input name="items" type="checkbox" value="' +
						items[i] + '">' + items[i]+ ' <br>';
		document.getElementById('catalog').innerHTML=catalog;
	}

	function shoppingCart_getResponse(feed) {
		if (feed != null) {
			var entries = feed.getElementsByTagName("entry");
			var list = "";
			for (var i=0; i<entries.length; i++) {
				var item = entries[i].getElementsByTagName("content")[0].firstChild.nodeValue;
				list += item + ' <br>';
			}
			document.getElementById("shoppingCart").innerHTML = list;
			document.getElementById('total').innerHTML = feed.getElementsByTagName("subtitle")[0].firstChild.nodeValue;
		}
	}
	function shoppingCart_postResponse(entry) {
		shoppingCart.get("", shoppingCart_getResponse);
	}


	function addToCart() {
		var items  = document.catalogForm.items;
		var j = 0;
		for (var i=0; i<items.length; i++)
			if (items[i].checked) {
				var entry = '<entry xmlns="http://www.w3.org/2005/Atom"><title>cart-item</title><content type="text">'+items[i].value+'</content></entry>'
				shoppingCart.post(entry, shoppingCart_postResponse);
				items[i].checked = false;
			}
	}
	function checkoutCart() {
		document.getElementById('store').innerHTML='<h2>' +
				'Thanks for Shopping With Us!</h2>'+
				'<h2>Your Order</h2>'+
				'<form name="orderForm" action="store.html">'+
					document.getElementById('shoppingCart').innerHTML+
					'<br>'+
					document.getElementById('total').innerHTML+
					'<br>'+
					'<br>'+
					'<input type="submit" value="Continue Shopping">'+
				'</form>';
		shoppingCart.del("", null);
	}
	function deleteCart() {
		shoppingCart.del("", null);
		document.getElementById('shoppingCart').innerHTML = "";
		document.getElementById('total').innerHTML = "";
	}

	catalog.get(catalog_getResponse);
	shoppingCart.get("", shoppingCart_getResponse);
</script>

</head>

<body>
<h1>Store</h1>
  <div id="store">
   	<h2>Catalog</h2>
   	<form name="catalogForm">
		<div id="catalog" ></div>
		<br>
		<input type="button" onClick="addToCart()"  value="Add to Cart">
   	</form>

 	<br>

   	<h2>Your Shopping Cart</h2>
   	<form name="shoppingCartForm">
		<div id="shoppingCart"></div>
		<br>
		<div id="total"></div>
		<br>
		<input type="button" onClick="checkoutCart()" value="Checkout">
		<input type="button" onClick="deleteCart()" value="Empty">
	   	<a href="../ShoppingCart/">(feed)</a>
	</form>
  </div>
</body>
</html>

After completing these steps the content of the "store" project will look as follows.

Compose Services

Now that you have all the required service implementations you compose them together to provide
the store composite service. The composition is stored in a .composite file.

Select the "src" folder of the "store" project. Right click to get the context menu, select New, and
then File. In the New File dialog enter "store.composite" for the File name, and then select Finish
to complete the dialog.

The Text editor will open on the new created composite file. Replace the content of the editor by
copy-paste of the following composite snippet.

<?xml version="1.0" encoding="UTF-8"?>
<composite xmlns="http://www.osoa.org/xmlns/sca/1.0"
	xmlns:t="http://tuscany.apache.org/xmlns/sca/1.0"
	xmlns:s="http://store"
	name="store">
	<component name="store">
		<t:implementation.widget location="ufservices/store.html"/>
		<service name="Widget">
			<t:binding.http/>
		</service>
                <reference name="catalog" target="Catalog">
		 	<t:binding.jsonrpc/>
		 </reference>
		 <reference name="shoppingCart" target="ShoppingCart">
		 	<t:binding.atom/>
		 </reference>
	</component>
	<component name="Catalog">
		<implementation.java class="services.CatalogImpl"/>
		<property name="currencyCode">USD</property>
		<service name="Catalog">
			<t:binding.jsonrpc/>
		</service>
		<reference name="currencyConverter" target="CurrencyConverter"/>
	</component>
	<component name="ShoppingCart">
		<implementation.java class="services.ShoppingCartImpl"/>
		<service name="Collection">
			<t:binding.atom/>
		</service>
	</component>
	<component name="CurrencyConverter">
		<implementation.java class="services.CurrencyConverterImpl"/>
	</component>
</composite>

After completing these steps the content of the "store" project will look as follows.

Launch Services

In this step you create the code to launch the Tuscany runtime with the new store composite
service you created.

Select the "store" project and click on the New Java Package button in the toolbar to start the

package creation dialog. Use the dialog to create a new package named "launch".
Select the "launch" package. Select the New Java Class button . In the dialog enter "Launch"
as the Name of the class, check the checkbox for creating a main method stub, and then select
Finish to complete the dialog.

The Java editor will open on the new created Java class. Replace the content of the editor by
copy-paste of the following Java class code snippet.

package launch;
import org.apache.tuscany.sca.host.embedded.SCADomain;
public class Launch {
	public static void main(String[] args) throws Exception {
		System.out.println("Starting ...");
		SCADomain scaDomain = SCADomain.newInstance("store.composite");
		System.out.println("store.composite ready for big business !!!");
		System.out.println();
		System.in.read();
		scaDomain.close();
	}
}

After completing these steps the content of the "store" project will look as follows.

Congratulations you completed your 1st composite service applications, now its time to take it into
action.

Use Services

In this step you launch and use the store composite service application you created.

First select the "Launch" class in the "launch" package of your "store" project. Right click to get the
context menu, select Run As, and then Java application. The Tuscany runtime will start up adding
the store composition to its domain.

The Eclipse console will show the following messages.

Next Launch your Web browser and enter the following address:

http://localhost:8080/store/store.html

You get to the Store user facing service of the composite service application.

You can select items from the Catalog and add them to your Shopping Cart.

Note: When adding items for the first time you will be asked for userid and password by the
browser. Enter "admin" for both.

Since the ShoppingCart service is bound using the ATOM binding, you can also look at the
shopping card content in ATOM feed form by clicking on the feed icon . You get the browsers default rendering for ATOM feeds.