🕐 feat: Configurable Retention Period for Temporary Chats (#8056)

* feat: Add configurable retention period for temporary chats

* Addressing eslint errors

* Fix: failing test due to missing registration

* Update: variable name and use hours instead of days for chat retention

* Addressing comments

* chore: fix import order in Conversation.js

* chore: import order in Message.js

* chore: fix import order in config.ts

* chore: move common methods to packages/api to reduce potential for circular dependencies

* refactor: update temp chat retention config type to Partial<TCustomConfig>

* refactor: remove unused config variable from AppService and update loadCustomConfig tests with logger mock

* refactor: handle model undefined edge case by moving Session model initialization inside methods

---------

Co-authored-by: Rakshit Tiwari <rak1729e@gmail.com>

packages/api/package.json

@@ -76,6 +76,7 @@
     "diff": "^7.0.0",
     "eventsource": "^3.0.2",
     "express": "^4.21.2",
+    "js-yaml": "^4.1.0",
     "keyv": "^5.3.2",
     "librechat-data-provider": "*",
     "node-fetch": "2.7.0",

packages/api/src/utils/events.ts

@@ -14,3 +14,13 @@ export function sendEvent(res: ServerResponse, event: ServerSentEvent): void {
   }
   res.write(`event: message\ndata: ${JSON.stringify(event)}\n\n`);
 }
+
+/**
+ * Sends error data in Server Sent Events format and ends the response.
+ * @param res - The server response.
+ * @param message - The error message.
+ */
+export function handleError(res: ServerResponse, message: string): void {
+  res.write(`event: error\ndata: ${JSON.stringify(message)}\n\n`);
+  res.end();
+}

packages/api/src/utils/index.ts

@@ -6,5 +6,8 @@ export * from './events';
 export * from './files';
 export * from './generators';
 export * from './llm';
+export * from './math';
 export * from './openid';
+export * from './tempChatRetention';
 export { default as Tokenizer } from './tokenizer';
+export * from './yaml';

packages/api/src/utils/math.ts

@@ -0,0 +1,45 @@
+/**
+ * Evaluates a mathematical expression provided as a string and returns the result.
+ *
+ * If the input is already a number, it returns the number as is.
+ * If the input is not a string or contains invalid characters, an error is thrown.
+ * If the evaluated result is not a number, an error is thrown.
+ *
+ * @param str - The mathematical expression to evaluate, or a number.
+ * @param fallbackValue - The default value to return if the input is not a string or number, or if the evaluated result is not a number.
+ *
+ * @returns The result of the evaluated expression or the input number.
+ *
+ * @throws Throws an error if the input is not a string or number, contains invalid characters, or does not evaluate to a number.
+ */
+export function math(str: string | number, fallbackValue?: number): number {
+  const fallback = typeof fallbackValue !== 'undefined' && typeof fallbackValue === 'number';
+  if (typeof str !== 'string' && typeof str === 'number') {
+    return str;
+  } else if (typeof str !== 'string') {
+    if (fallback) {
+      return fallbackValue;
+    }
+    throw new Error(`str is ${typeof str}, but should be a string`);
+  }
+
+  const validStr = /^[+\-\d.\s*/%()]+$/.test(str);
+
+  if (!validStr) {
+    if (fallback) {
+      return fallbackValue;
+    }
+    throw new Error('Invalid characters in string');
+  }
+
+  const value = eval(str);
+
+  if (typeof value !== 'number') {
+    if (fallback) {
+      return fallbackValue;
+    }
+    throw new Error(`[math] str did not evaluate to a number but to a ${typeof value}`);
+  }
+
+  return value;
+}

packages/api/src/utils/tempChatRetention.spec.ts

@@ -0,0 +1,133 @@
+import {
+  MIN_RETENTION_HOURS,
+  MAX_RETENTION_HOURS,
+  DEFAULT_RETENTION_HOURS,
+  getTempChatRetentionHours,
+  createTempChatExpirationDate,
+} from './tempChatRetention';
+import type { TCustomConfig } from 'librechat-data-provider';
+
+describe('tempChatRetention', () => {
+  const originalEnv = process.env;
+
+  beforeEach(() => {
+    jest.resetModules();
+    process.env = { ...originalEnv };
+    delete process.env.TEMP_CHAT_RETENTION_HOURS;
+  });
+
+  afterAll(() => {
+    process.env = originalEnv;
+  });
+
+  describe('getTempChatRetentionHours', () => {
+    it('should return default retention hours when no config or env var is set', () => {
+      const result = getTempChatRetentionHours();
+      expect(result).toBe(DEFAULT_RETENTION_HOURS);
+    });
+
+    it('should use environment variable when set', () => {
+      process.env.TEMP_CHAT_RETENTION_HOURS = '48';
+      const result = getTempChatRetentionHours();
+      expect(result).toBe(48);
+    });
+
+    it('should use config value when set', () => {
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 12,
+        },
+      };
+      const result = getTempChatRetentionHours(config);
+      expect(result).toBe(12);
+    });
+
+    it('should prioritize config over environment variable', () => {
+      process.env.TEMP_CHAT_RETENTION_HOURS = '48';
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 12,
+        },
+      };
+      const result = getTempChatRetentionHours(config);
+      expect(result).toBe(12);
+    });
+
+    it('should enforce minimum retention period', () => {
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 0,
+        },
+      };
+      const result = getTempChatRetentionHours(config);
+      expect(result).toBe(MIN_RETENTION_HOURS);
+    });
+
+    it('should enforce maximum retention period', () => {
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 10000,
+        },
+      };
+      const result = getTempChatRetentionHours(config);
+      expect(result).toBe(MAX_RETENTION_HOURS);
+    });
+
+    it('should handle invalid environment variable', () => {
+      process.env.TEMP_CHAT_RETENTION_HOURS = 'invalid';
+      const result = getTempChatRetentionHours();
+      expect(result).toBe(DEFAULT_RETENTION_HOURS);
+    });
+
+    it('should handle invalid config value', () => {
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 'invalid' as unknown as number,
+        },
+      };
+      const result = getTempChatRetentionHours(config);
+      expect(result).toBe(DEFAULT_RETENTION_HOURS);
+    });
+  });
+
+  describe('createTempChatExpirationDate', () => {
+    it('should create expiration date with default retention period', () => {
+      const result = createTempChatExpirationDate();
+
+      const expectedDate = new Date();
+      expectedDate.setHours(expectedDate.getHours() + DEFAULT_RETENTION_HOURS);
+
+      // Allow for small time differences in test execution
+      const timeDiff = Math.abs(result.getTime() - expectedDate.getTime());
+      expect(timeDiff).toBeLessThan(1000); // Less than 1 second difference
+    });
+
+    it('should create expiration date with custom retention period', () => {
+      const config: Partial<TCustomConfig> = {
+        interface: {
+          temporaryChatRetention: 12,
+        },
+      };
+
+      const result = createTempChatExpirationDate(config);
+
+      const expectedDate = new Date();
+      expectedDate.setHours(expectedDate.getHours() + 12);
+
+      // Allow for small time differences in test execution
+      const timeDiff = Math.abs(result.getTime() - expectedDate.getTime());
+      expect(timeDiff).toBeLessThan(1000); // Less than 1 second difference
+    });
+
+    it('should return a Date object', () => {
+      const result = createTempChatExpirationDate();
+      expect(result).toBeInstanceOf(Date);
+    });
+
+    it('should return a future date', () => {
+      const now = new Date();
+      const result = createTempChatExpirationDate();
+      expect(result.getTime()).toBeGreaterThan(now.getTime());
+    });
+  });
+});

packages/api/src/utils/tempChatRetention.ts

@@ -0,0 +1,77 @@
+import { logger } from '@librechat/data-schemas';
+import type { TCustomConfig } from 'librechat-data-provider';
+
+/**
+ * Default retention period for temporary chats in hours
+ */
+export const DEFAULT_RETENTION_HOURS = 24 * 30; // 30 days
+
+/**
+ * Minimum allowed retention period in hours
+ */
+export const MIN_RETENTION_HOURS = 1;
+
+/**
+ * Maximum allowed retention period in hours (1 year = 8760 hours)
+ */
+export const MAX_RETENTION_HOURS = 8760;
+
+/**
+ * Gets the temporary chat retention period from environment variables or config
+ * @param config - The custom configuration object
+ * @returns The retention period in hours
+ */
+export function getTempChatRetentionHours(config?: Partial<TCustomConfig> | null): number {
+  let retentionHours = DEFAULT_RETENTION_HOURS;
+
+  // Check environment variable first
+  if (process.env.TEMP_CHAT_RETENTION_HOURS) {
+    const envValue = parseInt(process.env.TEMP_CHAT_RETENTION_HOURS, 10);
+    if (!isNaN(envValue)) {
+      retentionHours = envValue;
+    } else {
+      logger.warn(
+        `Invalid TEMP_CHAT_RETENTION_HOURS environment variable: ${process.env.TEMP_CHAT_RETENTION_HOURS}. Using default: ${DEFAULT_RETENTION_HOURS} hours.`,
+      );
+    }
+  }
+
+  // Check config file (takes precedence over environment variable)
+  if (config?.interface?.temporaryChatRetention !== undefined) {
+    const configValue = config.interface.temporaryChatRetention;
+    if (typeof configValue === 'number' && !isNaN(configValue)) {
+      retentionHours = configValue;
+    } else {
+      logger.warn(
+        `Invalid temporaryChatRetention in config: ${configValue}. Using ${retentionHours} hours.`,
+      );
+    }
+  }
+
+  // Validate the retention period
+  if (retentionHours < MIN_RETENTION_HOURS) {
+    logger.warn(
+      `Temporary chat retention period ${retentionHours} is below minimum ${MIN_RETENTION_HOURS} hours. Using minimum value.`,
+    );
+    retentionHours = MIN_RETENTION_HOURS;
+  } else if (retentionHours > MAX_RETENTION_HOURS) {
+    logger.warn(
+      `Temporary chat retention period ${retentionHours} exceeds maximum ${MAX_RETENTION_HOURS} hours. Using maximum value.`,
+    );
+    retentionHours = MAX_RETENTION_HOURS;
+  }
+
+  return retentionHours;
+}
+
+/**
+ * Creates an expiration date for temporary chats
+ * @param config - The custom configuration object
+ * @returns The expiration date
+ */
+export function createTempChatExpirationDate(config?: Partial<TCustomConfig>): Date {
+  const retentionHours = getTempChatRetentionHours(config);
+  const expiredAt = new Date();
+  expiredAt.setHours(expiredAt.getHours() + retentionHours);
+  return expiredAt;
+}

packages/api/src/utils/yaml.ts

@@ -0,0 +1,11 @@
+import fs from 'fs';
+import yaml from 'js-yaml';
+
+export function loadYaml(filepath: string) {
+  try {
+    const fileContents = fs.readFileSync(filepath, 'utf8');
+    return yaml.load(fileContents);
+  } catch (e) {
+    return e;
+  }
+}