From d05a7fcef83ee900e26f58d00852ea030a6da0df Mon Sep 17 00:00:00 2001
From: Andrew <sapronov.a.v@yandex.ru>
Date: Thu, 19 Nov 2020 09:59:31 +0300
Subject: [PATCH] Made it possible to use JSON fields for data in the database

created a model with JSON data field

created option isDataFieldText in SequelizeStoreOptions, for connect model with JSON data field;
new model has been connected

created converting and reverse converting session data to string or to JSON
---
 index.d.ts                       |  3 ++-
 lib/connect-session-sequelize.js | 29 ++++++++++++++++++++---------
 lib/modelJson.js                 | 13 +++++++++++++
 3 files changed, 35 insertions(+), 10 deletions(-)
 create mode 100644 lib/modelJson.js

diff --git a/index.d.ts b/index.d.ts
index fc3c264..243d5f7 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -17,11 +17,12 @@ interface SequelizeStoreOptions {
   extendDefaultFields?: (defaults: DefaultFields, session: any) => Data;
   checkExpirationInterval?: number;
   expiration?: number;
+  isDataFieldText?: boolean;
 }
 
 declare class SequelizeStore extends Store {
   sync(): void
-  touch: (sid: string, data: any, callback?: (err: any) => void) => void
+  touch: (sid: string, data: any, callback?: (err: any) => void) => void;
   stopExpiringSessions: () => void
 }
 
diff --git a/lib/connect-session-sequelize.js b/lib/connect-session-sequelize.js
index 1e5a25e..c671148 100644
--- a/lib/connect-session-sequelize.js
+++ b/lib/connect-session-sequelize.js
@@ -6,14 +6,16 @@
  */
 
 const Op = require('sequelize').Op || {}
-const defaultModel = require('./model')
+const modelText = require('./model')
+const modelJson = require('./modelJson')
 const debug = require('debug')('connect:session-sequelize')
 const defaultOptions = {
   checkExpirationInterval: 15 * 60 * 1000, // The interval at which to cleanup expired sessions.
   expiration: 24 * 60 * 60 * 1000, // The maximum age (in milliseconds) of a valid session. Used when cookie.expires is not set.
   disableTouch: false, // When true, we will not update the db in the touch function call. Useful when you want more control over db writes.
   modelKey: 'Session',
-  tableName: 'Sessions'
+  tableName: 'Sessions',
+  isDataFieldText: true
 }
 
 function promisify (promise, fn) {
@@ -64,6 +66,7 @@ module.exports = function SequelizeSessionInit (Store) {
         // No Table specified, default to ./model
         debug('No table specified, using default table.')
         const modelKey = options.modelKey || 'Session'
+        const defaultModel = options.isDataFieldText? modelText : modelJson;
         this.sessionModel = options.db.define(modelKey, defaultModel, {
           tableName: options.tableName || modelKey
         })
@@ -79,14 +82,14 @@ module.exports = function SequelizeSessionInit (Store) {
       return promisify(
         this.sessionModel
           .findOne({ where: { sid: sid } })
-          .then(function (session) {
+          .then((session) => {
             if (!session) {
               debug('Did not find session %s', sid)
               return null
             }
             debug('FOUND %s with data %s', session.sid, session.data)
 
-            return JSON.parse(session.data)
+            return this.reverseConvertData(session.data)
           }),
         fn
       )
@@ -94,10 +97,10 @@ module.exports = function SequelizeSessionInit (Store) {
 
     set (sid, data, fn) {
       debug('INSERT "%s"', sid)
-      const stringData = JSON.stringify(data)
+      const convertedData = this.convertData(data);
       const expires = this.expiration(data)
 
-      let defaults = { data: stringData, expires: expires }
+      let defaults = { data: convertedData, expires: expires }
       if (this.options.extendDefaultFields) {
         defaults = this.options.extendDefaultFields(defaults, data)
       }
@@ -109,7 +112,7 @@ module.exports = function SequelizeSessionInit (Store) {
             defaults: defaults,
             raw: false
           })
-          .then(function sessionCreated ([session]) {
+          .then(([session]) => {
             let changed = false
             Object.keys(defaults).forEach(function (key) {
               if (key === 'data') {
@@ -121,8 +124,8 @@ module.exports = function SequelizeSessionInit (Store) {
                 changed = true
               }
             })
-            if (session.data !== stringData) {
-              session.data = JSON.stringify(data)
+            if (session.data !== convertedData) {
+              session.data = this.convertData(data)
               changed = true
             }
             if (changed) {
@@ -212,6 +215,14 @@ module.exports = function SequelizeSessionInit (Store) {
       }
       return new Date(Date.now() + this.options.expiration)
     }
+
+    convertData(data) {
+      return this.options.isDataFieldText? JSON.stringify(data) : data;
+    }
+    reverseConvertData(data) {
+      return this.options.isDataFieldText? JSON.parse(data) : data;
+    }
+
   }
 
   return SequelizeStore
diff --git a/lib/modelJson.js b/lib/modelJson.js
new file mode 100644
index 0000000..d2e57f1
--- /dev/null
+++ b/lib/modelJson.js
@@ -0,0 +1,13 @@
+/**
+ * Session Model with JSON data field
+ */
+const DataTypes = require('sequelize').DataTypes
+
+module.exports = {
+  sid: {
+    type: DataTypes.STRING(36),
+    primaryKey: true
+  },
+  expires: DataTypes.DATE,
+  data: DataTypes.JSON
+}