Changes between Version 1 and Version 2 of ObserverTutorial/Output

Timestamp:

06/21/10 16:42:25 (3 years ago)

Author:

jean-gui

Comment:

--

ObserverTutorial/Output

@@ +1 @@
+= Adapting calculator's output =
+For a web service to be able to send results back to Unicorn, it needs to implement a specific format called an observation response. Basically, this is an XML document listing all the messages (errors, warnings and information) that the web service produced.
+
+The following code shows how such a response would look like for the calculator. It contains two normal messages and an error. As you can see, each message has a type (info, warn, error), a context (optional) and a title. In our case, the context contains the arithmetic expression and the title contains the corresponding result. Each message element can have more data, like a longer text, an associated group, ... As you can see, there's also a status which is used to express if the test succeeded or failed. For a detailed description of this format check out its dedicated documentation.
+
 {{{
 #!xml
@@ -22 +27 @@
 
 }}}
+So, back to our calculator, we already have our results in an array and errors in another one, so it's easy to turn them into a Unicorn response:
+
 {{{
 #!xml
@@ -43 +50 @@
 <?php endforeach ?>
 </observationresponse>
+}}}
+Finally, we add it to the list of supported outputs in our main PHP script:
 
+{{{
+#!php
+$valid_formats[] = 'ucn';
 }}}
+Et voilà, we can now call the calculator with the parameter output=ucn to get results in Unicorn format.
+
+The [wiki:ObserverTutorial/Contract last step] as an observer developper will be to tell Unicorn how it can contact the service and which parameters to use. This is what we call the contract.