new plugin removeUnusedNS

plugins/removeUnusedNS.js

@@ -0,0 +1,100 @@
+/**
+ * Remove unused XLink namespace declaration.
+ *
+ * @param {Object} item current iteration item
+ * @param {Object} params plugin params
+ * @return {Boolean} if false, item will be filtered out
+ *
+ * @author Kir Belevich
+ */
+exports.removeUnusedNS = function(data, params) {
+
+    var svgElem,
+        xmlnsCollection = [];
+
+    /**
+     * Remove namespace from collection.
+     *
+     * @param {String} ns namescape name
+     */
+    function removeNSfromCollection(ns) {
+
+        var pos = xmlnsCollection.indexOf(ns);
+
+        // if found - remove ns from the namespaces collection
+        if (pos > -1) {
+            xmlnsCollection.splice(pos, 1);
+        }
+
+    }
+
+    /**
+     * Bananas!
+     *
+     * @param {Array} items input items
+     *
+     * @return {Array} output items
+     */
+    function monkeys(items) {
+
+        var i = 0,
+            length = items.content.length;
+
+        while(i < length) {
+
+            var item = items.content[i];
+
+            if (item.isElem('svg')) {
+
+                item.eachAttr(function(attr) {
+                    // collect namespaces
+                    if (attr.prefix === 'xmlns' && attr.local) {
+                        xmlnsCollection.push(attr.local);
+                    }
+                });
+
+                // if svg element has ns-attr
+                if (xmlnsCollection.length) {
+                    // save svg element
+                    svgElem = item;
+                }
+
+            } else if (xmlnsCollection.length) {
+
+                // check item for the ns-attrs
+                if (item.prefix) {
+                    removeNSfromCollection(item.prefix);
+                }
+
+                // check each attr for the ns-attrs
+                item.eachAttr(function(attr) {
+                    removeNSfromCollection(attr.prefix);
+                });
+
+            }
+
+            // if nothing is found - go deeper
+            if (xmlnsCollection.length && item.content) {
+                monkeys(item);
+            }
+
+            i++;
+
+        }
+
+        return items;
+
+    }
+
+    data = monkeys(data);
+
+    // remove svg element ns-attributes if they are not used even once
+    if (xmlnsCollection.length) {
+        xmlnsCollection.forEach(function(name) {
+            svgElem.removeAttr('xmlns:' + name);
+        });
+    }
+
+    return data;
+
+};