Implemented update middlewares

Author: Farhan Hasin Chowdhury

lib/simple-slugify.js

@@ -2,37 +2,29 @@
 
 const crypto = require('crypto');
 
-async function makeSlug(source, doc) {
-  const regex = /[&/\\#,+()$~%.'":*?<>{} ]/g;
-
-  let slug = doc[source].toString().toLowerCase().trim().replace(regex, '-');
-
-  try {
-    slug = (await doc.model(doc.constructor.modelName).exists({ slug }))
-      ? `${slug}-${crypto.randomBytes(5).toString('hex')}`
-      : slug;
-  } catch (error) {
-    // eslint-disable-next-line no-console
-    console.log(error);
-  }
-
-  return slug;
-}
+const regex = /[&/\\#,+()$~%.'":*?<>{} ]/g;
 
 module.exports = function (schema) {
   schema.pre(['save', 'updateOne'], async function (next) {
     const { source } = schema.tree.slug;
 
-    const doc = this;
+    let slug = this[source].toString().toLowerCase().trim().replace(regex, '-');
+
+    try {
+      slug = (await this.model(this.constructor.modelName).exists({ slug }))
+        ? `${slug}-${crypto.randomBytes(5).toString('hex')}`
+        : slug;
+    } catch (error) {
+      // eslint-disable-next-line no-console
+      console.log(error);
+    }
 
-    this.slug = await makeSlug(source, doc);
+    this.slug = slug;
 
     next();
   });
 
-  schema.pre(['findOneAndUpdate'], async function (next) {
-    const regex = /[&/\\#,+()$~%.'":*?<>{} ]/g;
-
+  schema.pre(['update', 'findOneAndUpdate'], async function (next) {
     let slug = this.get(this.schema.tree.slug.source)
       .toString()
       .toLowerCase()