Add transaction logging

core/database-connection-factory.js

@@ -1,6 +1,7 @@
 const Sequelize = require('sequelize');
 const fs = require('fs');
 const path = require('path');
+const TransactionLog = require('./transaction-log')
 
 const STORAGE_DIR = path.join(__base, 'storage');
 if (!fs.existsSync(STORAGE_DIR)) {
@@ -69,6 +70,9 @@ class DatabaseConnectionFactory {
     db.sequelize = sequelize;
     db.Sequelize = Sequelize;
 
+    const transactionLog = new TransactionLog(db);
+    transactionLog.setupSQLHooks(sequelize)
+
     return sequelize.authenticate().then(() =>
       sequelize.sync()
     ).thenReturn(db);

core/models/account/transaction.js

@@ -0,0 +1,18 @@
+module.exports = (sequelize, Sequelize) => {
+  const Transaction = sequelize.define('Transaction', {
+    type: Sequelize.STRING,
+    objectId: Sequelize.STRING,
+    modelName: Sequelize.STRING,
+    changedFields: {
+      type: Sequelize.STRING,
+      get: function get() {
+        return JSON.parse(this.getDataValue('changedFields'))
+      },
+      set: function set(val) {
+        this.setDataValue('changedFields', JSON.stringify(val));
+      },
+    },
+  });
+
+  return Transaction;
+};

core/transaction-log.js

@@ -0,0 +1,33 @@
+class TransactionLog {
+  constructor(db) {
+    this.db = db;
+  }
+
+  parseHookData({dataValues, _changed, $modelOptions}) {
+    return {
+      objectId: dataValues.id,
+      modelName: $modelOptions.name.singular,
+      changedFields: _changed,
+    }
+  }
+
+  isTransaction({$modelOptions}) {
+    return $modelOptions.name.singular === "Transaction"
+  }
+
+  transactionLogger(type) {
+    return (sequelizeHookData) => {
+      if (this.isTransaction(sequelizeHookData)) return;
+      this.db.Transaction.create(Object.assign({type: type},
+        this.parseHookData(sequelizeHookData)
+      ));
+    }
+  }
+
+  setupSQLHooks(sequelize) {
+    sequelize.addHook("afterCreate", this.transactionLogger("create"))
+    sequelize.addHook("afterUpdate", this.transactionLogger("update"))
+    sequelize.addHook("afterDelete", this.transactionLogger("delete"))
+  }
+}
+module.exports = TransactionLog