Application Design

• Site / Page Commands are normally activated by input from a caller. (Either spoken, in which case it will match a keyword, or keypad input, in which case it will match a touchtone value)
  
• You define in Voice Pages which destination to follow for each command, by selecting another Voice Page from the corresponding drop down.
  
• Site Commands are always active, and they are useful to implement global navigation or "top-level" navigation (following the website analogy, they are like the left or top navigation bar of a website)
  
• Page commands are only active in the Voice Page where they are defined.

Note that you point a Voice Page to another soon-to-exist Voice Page by selecting any of the "New ____ Page" options in a destination drop down. Upon saving the current Voice Page, the system will create the new page you requested and link to it from the page you saved.

Dealing with dynamic access points
In addition to static information playback, you may need to implement various useful behaviors. You may have defined these as dynamic access points or decision points in the call flow diagram. Here's a list of common tasks and how you can achieve them:

• Make a branching decision...
  • ... based on a schedule. If your Voice Site behaves differently depending on the time of the day, or the day of the week, you can simply implement this behavior with a Schedule Page.
    
  • ... based on information previously collected from the caller. Information you collect from callers is stored in variables. These variables can easily be manipulated with Logic Pages (coming later this month). In a Logic Page, you can make comparisons between variables and values you specify, and branch based on that.
    
  • ... based on caller profile information stored in another system. You may look up this information using a Transaction Page. Transaction Pages perform web requests (technically HTTP GETs or HTTP POSTs) and send Angel variables as parameters. The system can then interpret the response in various manners, including as "Links" or destinations of other Voice Pages. For example, you may extract the CallerID of an incoming call and look it up in your customer management system. If you find it, take the caller to the "Existing Customer" menu; otherwise you may take them to the "Are you a new or an existing customer?" menu.
• Play back a dynamic response...
  • ... to confirm caller input. The easiest way to achieve this is by means of playing back variables. Whenever you collect a response using a Question Page or collect a recording using a Voicemail Page, that response is available as a variable. You may define the variable name yourself, or if you haven't, the system will make a variable name based on the page name of the Question or Voicemail. A Message Page or a Yes/No Question Page may be used for playback. For example: "I heard you wanted: [3] medium t-shirts and [2] large t-shirts. Is that correct?" In this case, you may have two variables to confirm, such as medium_qty and large_qty. You can intersperse these variables with regular audio file or text-to-speech prompts to achieve the desired effect
  • ... with information from a transaction or a lookup in another system. If you need to acknowledge to the caller that something they requested has been received ("Your 8AM appointment has been scheduled") or to inform them of the outcome of a lookup ("Your order 45678 was shipped on February 19th"), you will need to configure the Angel system to perform a transaction via a Transaction Page. In the transaction you define the URL to a web script that takes information from Angel and returns a Voice Page that is dynamically generated via AngelXML. For more details on AngelXML please check the Transaction Page Reference Guide.
• Look up stored information that is specific to the Voice Site. If you have a simple voice application that reads tabular information, you can use a Data Page (coming later this month). Data Pages enable callers to look up information stored in an Excel spreadsheet uploaded into the Angel system. This is a great time saver, as you will be able to create dynamic and personalized interactions with no programming involved.
• Store information collected from a caller for later analysis. Another exciting aspect of Data Pages is their ability to store information collected from callers in a spreadsheet. This spreadsheet can be delivered to you via FTP or email on a scheduled basis.

Script development
In order for Transaction Pages to work, you will need to develop a web script that takes in the submitted variable information and produces a response that Angel can interpret. Although it can feel a little daunting at first, script development for Angel is actually quite easy, and you will get the hang of it quickly. Here are a few tips that will help you become a master:

• Develop in the scripting language you feel most comfortable with. Find a web server where you can store web scripts in your favorite language. I have met customers who develop their applications in Java, ASP, .NET, Perl, PHP, Coldfusion, 4th Dimension, CGI/shell, and many more!
  
• A submission from Angel to your script is like a submission from an HTML form. Just like you can define an HTML form with the FORM tag, you can define a "form" via the interface of a Transaction Page. The URL in the Transaction Page is the equivalent of the "action" tag.
  
• Instead of returning HTML for display in a web browser, return plain text that Angel can interpret. As your script performs an operation, it should return text that Angel can interpret as one of the following: text-to-speech to play back to the caller (e.g.: "Thank you. Your order was received"), A link to another Voice Page (e.g.: "/32" interpreted as an instruction to go to page 32 of the current Voice Site), the name of a sound file to play back (e.g.: "thankyou.wav"), a phone number to transfer to (e.g.: "7032866415"), or the full URL to a sound file (e.g.: http://yourserver/path/filename.wav).
• If you need to do more sophisticated stuff, have your script return AngelXML. This is a powerful but simple XML language that allows you to define most properties of a Voice Page that only exists for the duration of its playback.
• Save time by testing your script responses from Site Builder. In every Transaction Page you will find fields where you can enter test values. You can then press the "Run Test" button. This will invoke your script with the test values entered, and display for you what the Angel system received as a response, and whether the response was valid.
  
• Turn on email debugging to uncover runtime problems. In the Advanced Options of a Transaction Page, you can enter an email address that the system can use to notify you when a caller experienced an error related to the execution of your script. The email will include all the contextual information you require
• Reuse publicly available scripts. Many useful functions have been encapsulated in publicly available web services. For more information on this subject check out Get Lazy with Public Web Services. In addition, the Angel Solutions team has produced many scripts that perform useful functions that you can leverage. We'd be happy to share them with you. Just check with us via the Support Center.