BREAKING CHANGE(localtsmdb): add Unix socket support and change LocalTsmDb API to return connection info instead of a MongoClient

ts/ts_tsmdb/server/TsmdbServer.ts

@@ -1,4 +1,5 @@
 import * as net from 'net';
+import * as fs from 'fs/promises';
 import * as plugins from '../plugins.js';
 import { WireProtocol, OP_QUERY } from './WireProtocol.js';
 import { CommandRouter } from './CommandRouter.js';
@@ -10,10 +11,12 @@ import type { IStorageAdapter } from '../storage/IStorageAdapter.js';
  * Server configuration options
  */
 export interface ITsmdbServerOptions {
-  /** Port to listen on (default: 27017) */
+  /** Port to listen on (default: 27017) - ignored if socketPath is set */
   port?: number;
-  /** Host to bind to (default: 127.0.0.1) */
+  /** Host to bind to (default: 127.0.0.1) - ignored if socketPath is set */
   host?: string;
+  /** Unix socket path - if set, server listens on socket instead of TCP */
+  socketPath?: string;
   /** Storage type: 'memory' or 'file' (default: 'memory') */
   storage?: 'memory' | 'file';
   /** Path for file storage (required if storage is 'file') */
@@ -54,7 +57,7 @@ interface IConnectionState {
  * ```
  */
 export class TsmdbServer {
-  private options: Required<ITsmdbServerOptions>;
+  private options: Required<Omit<ITsmdbServerOptions, 'socketPath'>> & { socketPath: string };
   private server: net.Server | null = null;
   private storage: IStorageAdapter;
   private commandRouter: CommandRouter;
@@ -62,11 +65,14 @@ export class TsmdbServer {
   private connectionIdCounter = 0;
   private isRunning = false;
   private startTime: Date = new Date();
+  private useSocket: boolean;
 
   constructor(options: ITsmdbServerOptions = {}) {
+    this.useSocket = !!options.socketPath;
     this.options = {
       port: options.port ?? 27017,
       host: options.host ?? '127.0.0.1',
+      socketPath: options.socketPath ?? '',
       storage: options.storage ?? 'memory',
       storagePath: options.storagePath ?? './data',
       persistPath: options.persistPath ?? '',
@@ -119,6 +125,18 @@ export class TsmdbServer {
     // Initialize storage
     await this.storage.initialize();
 
+    // Clean up stale socket file if using Unix socket
+    if (this.useSocket && this.options.socketPath) {
+      try {
+        await fs.unlink(this.options.socketPath);
+      } catch (err: any) {
+        // Ignore ENOENT (file doesn't exist)
+        if (err.code !== 'ENOENT') {
+          throw err;
+        }
+      }
+    }
+
     return new Promise((resolve, reject) => {
       this.server = net.createServer((socket) => {
         this.handleConnection(socket);
@@ -132,11 +150,21 @@ export class TsmdbServer {
         }
       });
 
-      this.server.listen(this.options.port, this.options.host, () => {
-        this.isRunning = true;
-        this.startTime = new Date();
-        resolve();
-      });
+      if (this.useSocket && this.options.socketPath) {
+        // Listen on Unix socket
+        this.server.listen(this.options.socketPath, () => {
+          this.isRunning = true;
+          this.startTime = new Date();
+          resolve();
+        });
+      } else {
+        // Listen on TCP
+        this.server.listen(this.options.port, this.options.host, () => {
+          this.isRunning = true;
+          this.startTime = new Date();
+          resolve();
+        });
+      }
     });
   }
 
@@ -161,9 +189,22 @@ export class TsmdbServer {
     await this.storage.close();
 
     return new Promise((resolve) => {
-      this.server!.close(() => {
+      this.server!.close(async () => {
         this.isRunning = false;
         this.server = null;
+
+        // Clean up socket file if using Unix socket
+        if (this.useSocket && this.options.socketPath) {
+          try {
+            await fs.unlink(this.options.socketPath);
+          } catch (err: any) {
+            // Ignore ENOENT (file doesn't exist)
+            if (err.code !== 'ENOENT') {
+              console.error('Failed to remove socket file:', err);
+            }
+          }
+        }
+
         resolve();
       });
     });
@@ -275,9 +316,21 @@ export class TsmdbServer {
    * Get the connection URI for this server
    */
   getConnectionUri(): string {
+    if (this.useSocket && this.options.socketPath) {
+      // URL-encode the socket path (replace / with %2F)
+      const encodedPath = encodeURIComponent(this.options.socketPath);
+      return `mongodb://${encodedPath}`;
+    }
     return `mongodb://${this.options.host}:${this.options.port}`;
   }
 
+  /**
+   * Get the socket path (if using Unix socket mode)
+   */
+  get socketPath(): string | undefined {
+    return this.useSocket ? this.options.socketPath : undefined;
+  }
+
   /**
    * Check if the server is running
    */