added `parseTagList`

lib/site-common.js

@@ -7,6 +7,8 @@
 const path = require('path');
 const pug = require('pug');
 
+const striptags = require('striptags');
+
 const { SiteLog } = require(path.join(__dirname, 'site-log'));
 const { SiteAsync } = require(path.join(__dirname, 'site-async'));
 
@@ -102,6 +104,25 @@ class SiteCommon extends Events {
     }, options);
     return pug.compileFileClient(scriptFile, options);
   }
+
+  parseTagList (tagList, options) {
+    options = Object.assign({
+      lowercase: true,
+      filter: [ ],
+    }, options);
+    return tagList
+      .split(',')
+      .map((metric) => {
+        metric = striptags(metric.trim());
+        return options.lowercase ? metric.toLowerCase() : metric;
+      })
+      .filter((metric) => {
+        return  (typeof metric === 'string') &&
+                (metric.length > 0) &&
+                !options.filter.includes(metric.toLowerCase())
+        ;
+      });
+  }
 }
 
 module.exports.SiteCommon = SiteCommon;