fix(ssh): introduce SshRetryHandler and SshRetryable trait for enhanced SSH command retry logic with exponential backoff and error handling

tests/Unit/SshRetryMechanismTest.php

@@ -0,0 +1,189 @@
+<?php
+
+namespace Tests\Unit;
+
+use App\Helpers\SshRetryHandler;
+use App\Traits\SshRetryable;
+use Tests\TestCase;
+
+class SshRetryMechanismTest extends TestCase
+{
+    public function test_ssh_retry_handler_exists()
+    {
+        $this->assertTrue(class_exists(\App\Helpers\SshRetryHandler::class));
+    }
+
+    public function test_ssh_retryable_trait_exists()
+    {
+        $this->assertTrue(trait_exists(\App\Traits\SshRetryable::class));
+    }
+
+    public function test_retry_on_ssh_connection_errors()
+    {
+        $handler = new class
+        {
+            use SshRetryable;
+
+            // Make methods public for testing
+            public function test_is_retryable_ssh_error($error)
+            {
+                return $this->isRetryableSshError($error);
+            }
+        };
+
+        // Test various SSH error patterns
+        $sshErrors = [
+            'kex_exchange_identification: read: Connection reset by peer',
+            'Connection refused',
+            'Connection timed out',
+            'ssh_exchange_identification: Connection closed by remote host',
+            'Broken pipe',
+            'No route to host',
+            'Network is unreachable',
+        ];
+
+        foreach ($sshErrors as $error) {
+            $this->assertTrue(
+                $handler->test_is_retryable_ssh_error($error),
+                "Failed to identify as retryable: $error"
+            );
+        }
+    }
+
+    public function test_non_ssh_errors_are_not_retryable()
+    {
+        $handler = new class
+        {
+            use SshRetryable;
+
+            // Make methods public for testing
+            public function test_is_retryable_ssh_error($error)
+            {
+                return $this->isRetryableSshError($error);
+            }
+        };
+
+        // Test non-SSH errors
+        $nonSshErrors = [
+            'Command not found',
+            'Permission denied',
+            'File not found',
+            'Syntax error',
+            'Invalid argument',
+        ];
+
+        foreach ($nonSshErrors as $error) {
+            $this->assertFalse(
+                $handler->test_is_retryable_ssh_error($error),
+                "Incorrectly identified as retryable: $error"
+            );
+        }
+    }
+
+    public function test_exponential_backoff_calculation()
+    {
+        $handler = new class
+        {
+            use SshRetryable;
+
+            // Make method public for testing
+            public function test_calculate_retry_delay($attempt)
+            {
+                return $this->calculateRetryDelay($attempt);
+            }
+        };
+
+        // Test with default config values
+        config(['constants.ssh.retry_base_delay' => 2]);
+        config(['constants.ssh.retry_max_delay' => 30]);
+        config(['constants.ssh.retry_multiplier' => 2]);
+
+        // Attempt 0: 2 seconds
+        $this->assertEquals(2, $handler->test_calculate_retry_delay(0));
+
+        // Attempt 1: 4 seconds
+        $this->assertEquals(4, $handler->test_calculate_retry_delay(1));
+
+        // Attempt 2: 8 seconds
+        $this->assertEquals(8, $handler->test_calculate_retry_delay(2));
+
+        // Attempt 3: 16 seconds
+        $this->assertEquals(16, $handler->test_calculate_retry_delay(3));
+
+        // Attempt 4: Should be capped at 30 seconds
+        $this->assertEquals(30, $handler->test_calculate_retry_delay(4));
+
+        // Attempt 5: Should still be capped at 30 seconds
+        $this->assertEquals(30, $handler->test_calculate_retry_delay(5));
+    }
+
+    public function test_retry_succeeds_after_failures()
+    {
+        $attemptCount = 0;
+
+        config(['constants.ssh.max_retries' => 3]);
+
+        // Simulate a function that fails twice then succeeds using the public static method
+        $result = SshRetryHandler::retry(
+            function () use (&$attemptCount) {
+                $attemptCount++;
+                if ($attemptCount < 3) {
+                    throw new \RuntimeException('kex_exchange_identification: Connection reset by peer');
+                }
+
+                return 'success';
+            },
+            ['test' => 'retry_test'],
+            true
+        );
+
+        $this->assertEquals('success', $result);
+        $this->assertEquals(3, $attemptCount);
+    }
+
+    public function test_retry_fails_after_max_attempts()
+    {
+        $attemptCount = 0;
+
+        config(['constants.ssh.max_retries' => 3]);
+
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('Connection reset by peer');
+
+        // Simulate a function that always fails using the public static method
+        SshRetryHandler::retry(
+            function () use (&$attemptCount) {
+                $attemptCount++;
+                throw new \RuntimeException('Connection reset by peer');
+            },
+            ['test' => 'retry_test'],
+            true
+        );
+    }
+
+    public function test_non_retryable_errors_fail_immediately()
+    {
+        $attemptCount = 0;
+
+        config(['constants.ssh.max_retries' => 3]);
+
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('Command not found');
+
+        try {
+            // Simulate a non-retryable error using the public static method
+            SshRetryHandler::retry(
+                function () use (&$attemptCount) {
+                    $attemptCount++;
+                    throw new \RuntimeException('Command not found');
+                },
+                ['test' => 'non_retryable_test'],
+                true
+            );
+        } catch (\RuntimeException $e) {
+            // Should only attempt once since it's not retryable
+            $this->assertEquals(1, $attemptCount);
+            throw $e;
+        }
+    }
+}