Merge lp:~milo/linaro-ci-dashboard/xml-chaining-definition into lp:linaro-ci-dashboard

[Milo Casagrande]

This adds a section in the HACKING file about loop chaining and the XML format used to exchange information between loops.

XML format will probably be expanded, this is the initial definition.

[Stevan Radaković (stevanr)]

Looks good.
Approve +1.

review: Approve (documentation)

=== modified file 'HACKING'
--- HACKING	2012-08-24 08:40:11 +0000
+++ HACKING	2012-08-30 10:11:37 +0000
@@ -48,3 +48,35 @@
 `dashboard/'.
 
 Tests should be written and defined inside each sub-application.
+
+= Loop Chaining =
+
+Loop chaining in the linaro-ci-dashboard is a mechanism to use output from one
+loop as input for another loop. Loops have to be "chainable", in the sense that
+output of one must be valid to be used as the input of another one.
+
+== XML Format Definition ==
+
+This is the XML format definition for loop-chaining, with DTD and simple
+example.
+
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE loop [
+    <!ATTLIST loop (name, type) PCDATA #REQUIRED>
+    <!ATTLIST loop (next) CDATA #OPTIONAL>
+    <!ELEMENT description (#PCDATA)>
+    <!ELEMENT restricted (#PCDATA)>
+    <!ELEMENT official (#PCDATA)>
+    <!ELEMENT fields (field+)>
+    <!ELEMENT field (#PCDATA)>
+    <!ATTLIST field (name, type) PCDATA #REQUIRED>
+]>
+<loop name="" type="" next="">
+    <restricted></restricted>
+    <official></official>
+    <fields>
+        <field name="" type=""></field>
+        <field name="" type=""></field>
+        <field name="" type=""></field>
+    </fields>
+</loop>