Implement basic version of ssh shell

Signed-off-by: Vladimir Domnich <v.domnich@yadro.com>

tests/test_ssh_shell.py

@@ -0,0 +1,138 @@
+import os
+from unittest import SkipTest, TestCase
+
+from shell.interfaces import CommandOptions, InteractiveInput
+from shell.ssh_shell import SSHShell
+from tests.helpers import format_error_details, get_output_lines
+
+
+def init_shell() -> SSHShell:
+    host = os.getenv("SSH_SHELL_HOST")
+    port = os.getenv("SSH_SHELL_PORT", "22")
+    login = os.getenv("SSH_SHELL_LOGIN")
+    private_key_path = os.getenv("SSH_SHELL_PRIVATE_KEY_PATH")
+    private_key_passphrase = os.getenv("SSH_SHELL_PRIVATE_KEY_PASSPHRASE")
+
+    if not all([host, login, private_key_path, private_key_passphrase]):
+        # TODO: in the future we might use https://pypi.org/project/mock-ssh-server,
+        # at the moment it is not suitable for us because of its issues with stdin
+        raise SkipTest("SSH connection is not configured")
+
+    return SSHShell(
+        host=host,
+        port=port,
+        login=login,
+        private_key_path=private_key_path,
+        private_key_passphrase=private_key_passphrase,
+    )
+
+
+class TestSSHShellInteractive(TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.shell = init_shell()
+
+    def test_command_with_one_prompt(self):
+        script = "password = input('Password: '); print('\\n' + password)"
+
+        inputs = [InteractiveInput(prompt_pattern="Password", input="test")]
+        result = self.shell.exec(
+            f'python3 -c "{script}"', CommandOptions(interactive_inputs=inputs)
+        )
+
+        # TODO: we have inconsistency with local shell here, ssh does not echo input into stdout
+        self.assertEqual(0, result.return_code)
+        self.assertEqual(["Password:", "test"], get_output_lines(result))
+        self.assertEqual("", result.stderr)
+
+    def test_command_with_several_prompts(self):
+        script = (
+            "input1 = input('Input1: '); print('\\n' + input1); "
+            "input2 = input('Input2: '); print('\\n' + input2)"
+        )
+        inputs = [
+            InteractiveInput(prompt_pattern="Input1", input="test1"),
+            InteractiveInput(prompt_pattern="Input2", input="test2"),
+        ]
+
+        result = self.shell.exec(
+            f'python3 -c "{script}"', CommandOptions(interactive_inputs=inputs)
+        )
+
+        # TODO: we have inconsistency with local shell here, ssh does not echo input into stdout
+        self.assertEqual(0, result.return_code)
+        self.assertEqual(["Input1:", "test1", "Input2:", "test2"], get_output_lines(result))
+        self.assertEqual("", result.stderr)
+
+    def test_invalid_command_with_check(self):
+        script = "invalid script"
+        inputs = [InteractiveInput(prompt_pattern=".*", input="test")]
+
+        with self.assertRaises(RuntimeError) as raised:
+            self.shell.exec(f'python3 -c "{script}"', CommandOptions(interactive_inputs=inputs))
+
+        error = format_error_details(raised.exception)
+        self.assertIn("Error", error)
+        self.assertIn("return code: 1", error)
+
+    def test_invalid_command_without_check(self):
+        script = "invalid script"
+        inputs = [InteractiveInput(prompt_pattern=".*", input="test")]
+
+        result = self.shell.exec(
+            f'python3 -c "{script}"',
+            CommandOptions(interactive_inputs=inputs, check=False),
+        )
+        self.assertEqual(1, result.return_code)
+
+    def test_non_existing_binary(self):
+        inputs = [InteractiveInput(prompt_pattern=".*", input="test")]
+
+        with self.assertRaises(RuntimeError) as raised:
+            self.shell.exec("not-a-command", CommandOptions(interactive_inputs=inputs))
+
+        error = format_error_details(raised.exception)
+        self.assertIn("return code: 127", error)
+
+
+class TestSSHShellNonInteractive(TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.shell = init_shell()
+
+    def test_correct_command(self):
+        script = "print('test')"
+
+        result = self.shell.exec(f'python3 -c "{script}"')
+
+        self.assertEqual(0, result.return_code)
+        self.assertEqual("test", result.stdout.strip())
+        self.assertEqual("", result.stderr)
+
+    def test_invalid_command_with_check(self):
+        script = "invalid script"
+
+        with self.assertRaises(RuntimeError) as raised:
+            self.shell.exec(f'python3 -c "{script}"')
+
+        error = format_error_details(raised.exception)
+        self.assertIn("Error", error)
+        self.assertIn("return code: 1", error)
+
+    def test_invalid_command_without_check(self):
+        script = "invalid script"
+
+        result = self.shell.exec(f'python3 -c "{script}"', CommandOptions(check=False))
+
+        self.assertEqual(1, result.return_code)
+        # TODO: we have inconsistency with local shell here, the local shell captures error info
+        # in stdout while ssh shell captures it in stderr
+        self.assertIn("Error", result.stderr)
+
+    def test_non_existing_binary(self):
+        with self.assertRaises(RuntimeError) as exc:
+            self.shell.exec("not-a-command")
+
+        error = format_error_details(exc.exception)
+        self.assertIn("Error", error)
+        self.assertIn("return code: 127", error)