From e24d9d0ab39c52c7742673818f3a13d367ebb97b Mon Sep 17 00:00:00 2001
From: abdou6666 <sfayhi.abderrahmen@esprit.tn>
Date: Sun, 26 Jan 2025 19:42:13 +0100
Subject: [PATCH] feat: support transactions mongodb

---
 .../transaction-manager/TransactionManager.ts | 62 +++++++++++++++++++
 .../TransactionManagerFactory.ts              | 37 +++++++++++
 2 files changed, 99 insertions(+)
 create mode 100644 api/src/transaction-manager/TransactionManager.ts
 create mode 100644 api/src/transaction-manager/TransactionManagerFactory.ts

diff --git a/api/src/transaction-manager/TransactionManager.ts b/api/src/transaction-manager/TransactionManager.ts
new file mode 100644
index 000000000..9304345f1
--- /dev/null
+++ b/api/src/transaction-manager/TransactionManager.ts
@@ -0,0 +1,62 @@
+/*
+ * Copyright © 2025 Hexastack. All rights reserved.
+ *
+ * Licensed under the GNU Affero General Public License v3.0 (AGPLv3) with the following additional terms:
+ * 1. The name "Hexabot" is a trademark of Hexastack. You may not use this name in derivative works without express written permission.
+ * 2. All derivative works must include clear attribution to the original creator and software, Hexastack and Hexabot, in a prominent location (e.g., in the software's "About" section, documentation, and README file).
+ */
+
+import { ClientSession } from 'mongoose';
+
+// TODO: logging
+export class TransactionManager {
+  private hasCommited = false;
+
+  private hasAborted = false;
+
+  private hasEnded = false;
+
+  private callbackHasErrored = false;
+
+  constructor(private session: ClientSession) {
+    this.session.startTransaction();
+  }
+
+  async withTransaction<T>(
+    callback: (session: ClientSession) => Promise<T>,
+  ): Promise<T> {
+    try {
+      const result = await callback(this.session).catch((err) => {
+        this.callbackHasErrored = true;
+        throw err;
+      });
+
+      await this.commitTransaction();
+      return result;
+    } catch (error) {
+      await this.abortTransaction();
+      throw error;
+    } finally {
+      await this.endTransaction();
+    }
+  }
+
+  private async commitTransaction() {
+    if (this.session.inTransaction()) {
+      await this.session.commitTransaction();
+      this.hasCommited = true;
+    }
+  }
+
+  private async abortTransaction() {
+    if (this.session.inTransaction()) {
+      await this.session.abortTransaction();
+      this.hasAborted = true;
+    }
+  }
+
+  private async endTransaction() {
+    await this.session.endSession();
+    this.hasEnded = true;
+  }
+}
diff --git a/api/src/transaction-manager/TransactionManagerFactory.ts b/api/src/transaction-manager/TransactionManagerFactory.ts
new file mode 100644
index 000000000..0878635d4
--- /dev/null
+++ b/api/src/transaction-manager/TransactionManagerFactory.ts
@@ -0,0 +1,37 @@
+/*
+ * Copyright © 2025 Hexastack. All rights reserved.
+ *
+ * Licensed under the GNU Affero General Public License v3.0 (AGPLv3) with the following additional terms:
+ * 1. The name "Hexabot" is a trademark of Hexastack. You may not use this name in derivative works without express written permission.
+ * 2. All derivative works must include clear attribution to the original creator and software, Hexastack and Hexabot, in a prominent location (e.g., in the software's "About" section, documentation, and README file).
+ */
+
+import {
+  HttpException,
+  HttpStatus,
+  Injectable,
+  LoggerService,
+} from '@nestjs/common';
+import { InjectConnection } from '@nestjs/mongoose';
+import { Connection } from 'mongoose';
+
+import { TransactionManager } from './TransactionManager';
+
+// TODO: logging / update mongodb docker file replicas
+@Injectable()
+export class TransactionManagerFactory {
+  constructor(
+    @InjectConnection() private readonly connection: Connection,
+    private loggerService: LoggerService,
+  ) {}
+
+  async create(): Promise<TransactionManager> {
+    const session = await this.connection.startSession().catch((_err) => {
+      throw new HttpException(
+        `Something went wrong while start transaction session`,
+        HttpStatus.INTERNAL_SERVER_ERROR,
+      );
+    });
+    return new TransactionManager(session);
+  }
+}