feat: Add LOCK_TIMEOUT connection setting

src/connection.ts

@@ -387,6 +387,7 @@ export interface InternalConnectionOptions {
   isolationLevel: typeof ISOLATION_LEVEL[keyof typeof ISOLATION_LEVEL];
   language: string;
   localAddress: undefined | string;
+  lockTimeout: undefined | number;
   maxRetriesOnTransientErrors: number;
   multiSubnetFailover: boolean;
   packetSize: number;
@@ -734,6 +735,13 @@ export interface ConnectionOptions {
    */
   localAddress?: string | undefined;
 
+  /**
+   * The number of milliseconds a statement waits for a lock to be released.
+   * This sets the value for `SET LOCK_TIMEOUT` during the initial SQL phase of a connection.
+   * For more information, see [here](https://learn.microsoft.com/en-us/sql/t-sql/statements/set-lock-timeout-transact-sql)
+   */
+  lockTimeout?: number | undefined;
+
   /**
    * A boolean determining whether to parse unique identifier type with lowercase case characters.
    *
@@ -1306,6 +1314,7 @@ class Connection extends EventEmitter {
         isolationLevel: ISOLATION_LEVEL.READ_COMMITTED,
         language: DEFAULT_LANGUAGE,
         localAddress: undefined,
+        lockTimeout: undefined,
         maxRetriesOnTransientErrors: 3,
         multiSubnetFailover: false,
         packetSize: DEFAULT_PACKET_SIZE,
@@ -1592,6 +1601,14 @@ class Connection extends EventEmitter {
         this.config.options.localAddress = config.options.localAddress;
       }
 
+      if (config.options.lockTimeout !== undefined) {
+        if (typeof config.options.lockTimeout !== 'number') {
+          throw new TypeError('The "config.options.lockTimeout" property must be of type number.');
+        }
+
+        this.config.options.lockTimeout = config.options.lockTimeout;
+      }
+
       if (config.options.multiSubnetFailover !== undefined) {
         if (typeof config.options.multiSubnetFailover !== 'boolean') {
           throw new TypeError('The "config.options.multiSubnetFailover" property must be of type boolean.');
@@ -2595,6 +2612,10 @@ class Connection extends EventEmitter {
       options.push(`set language ${this.config.options.language}`);
     }
 
+    if (this.config.options.lockTimeout !== undefined) {
+      options.push(`set lock_timeout ${this.config.options.lockTimeout}`);
+    }
+
     if (this.config.options.enableNumericRoundabort === true) {
       options.push('set numeric_roundabort on');
     } else if (this.config.options.enableNumericRoundabort === false) {

test/integration/connection-test.js

@@ -2268,3 +2268,56 @@ describe('Boolean Config Options Test', function() {
     testBadBooleanConfigOption(done, 'abortTransactionOnError');
   });
 });
+
+describe('should test lock timeout', function() {
+  /**
+   * @param {Mocha.Done} done
+   * @param {number | undefined} lockTimeout
+   */
+  function testLockTimeout(done, lockTimeout) {
+    const config = getConfig();
+
+    const connection = new Connection({
+      ...config,
+      options: {
+        ...config.options,
+        lockTimeout: lockTimeout
+      }
+    });
+    lockTimeout = lockTimeout ?? -1;
+
+    if (process.env.TEDIOUS_DEBUG) {
+      connection.on('debug', console.log);
+    }
+
+    const request = new Request(
+      'SELECT @@LOCK_TIMEOUT',
+      function(err) {
+        assert.ifError(err);
+        connection.close();
+      }
+    );
+
+    request.on('row', function(columns) {
+      const lockTimeoutActual = columns[0].value;
+      assert.strictEqual(lockTimeoutActual, lockTimeout);
+    });
+
+    connection.connect(function(err) {
+      assert.ifError(err);
+      connection.execSql(request);
+    });
+
+    connection.on('end', function() {
+      done();
+    });
+  }
+
+  it('should test lock timeout default', function(done) {
+    testLockTimeout(done, undefined);
+  });
+
+  it('should test lock timeout custom', function(done) {
+    testLockTimeout(done, 1000);
+  });
+});