Basic support for writing XML namespaces

1 files changed, 45 insertions, 24 deletions

diff --git a/lib/xml/writer.js b/lib/xml/writer.js
index 418a4b9..66cc8de 100644
--- a/lib/xml/writer.js
+++ b/lib/xml/writer.js
@@ -1,36 +1,57 @@
+var _ = require("underscore");
 var xmlbuilder = require("xmlbuilder");
 
 
 exports.writeString = writeString;
 
 
-function writeString(root) {
-    var builder = xmlbuilder
-        .create(root.name, {
-            version: '1.0',
-            encoding: 'UTF-8',
-            standalone: true
-        });
-    root.children.forEach(function(child) {
-        writeNode(builder, child);
-    });
-    return builder.end();
-}
+function writeString(root, namespaces) {
+    var uriToPrefix = _.invert(namespaces);
+    
+    var nodeWriters = {
+        element: writeElement,
+        text: writeTextNode
+    };
 
-var nodeWriters = {
-    element: writeElement,
-    text: writeTextNode
-};
+    function writeNode(builder, node) {
+        return nodeWriters[node.type](builder, node);
+    }
 
-function writeNode(builder, node) {
-    return nodeWriters[node.type](builder, node);
-}
+    function writeElement(builder, element) {
+        var elementBuilder = builder.element(mapElementName(element.name), element.attributes);
+        element.children.forEach(function(child) {
+            writeNode(elementBuilder, child);
+        });
+    }
+    
+    function mapElementName(name) {
+        var longFormMatch = /^\{(.*)\}(.*)$/.exec(name);
+        if (longFormMatch) {
+            return uriToPrefix[longFormMatch[1]] + ":" + longFormMatch[2];
+        } else {
+            return name;
+        }
+    }
+    
+    function writeDocument(root) {
+        var builder = xmlbuilder
+            .create(root.name, {
+                version: '1.0',
+                encoding: 'UTF-8',
+                standalone: true
+            });
+        
+        _.forEach(namespaces, function(uri, prefix) {
+            builder.attribute("xmlns:" + prefix, uri);
+        });
+        
+        root.children.forEach(function(child) {
+            writeNode(builder, child);
+        });
+        return builder.end();
+    }
 
-function writeElement(builder, element) {
-    var elementBuilder = builder.element(element.name, element.attributes);
-    element.children.forEach(function(child) {
-        writeNode(elementBuilder, child);
-    });
+    return writeDocument(root);
 }
 
 function writeTextNode(builder, node) {