Add loader and sceanrio runner interfaces, add support for local scenario

Signed-off-by: Andrey Berezin <a.berezin@yadro.com>

src/frostfs_testlib/shell/command_inspectors.py

@@ -7,7 +7,23 @@ class SudoInspector(CommandInspector):
     If command is already prepended with sudo, then has no effect.
     """
 
-    def inspect(self, command: str) -> str:
+    def inspect(self, original_command: str, command: str) -> str:
         if not command.startswith("sudo"):
             return f"sudo {command}"
         return command
+
+
+class SuInspector(CommandInspector):
+    """Allows to run command as another user via sudo su call
+
+    If command is already prepended with sudo su, then has no effect.
+    """
+
+    def __init__(self, user: str) -> None:
+        self.user = user
+
+    def inspect(self, original_command: str, command: str) -> str:
+        if not original_command.startswith("sudo su"):
+            cmd = original_command.replace('"', '\\"').replace("\$", "\\\\\\$")
+            return f'sudo su - {self.user} -c "{cmd}"'
+        return original_command

src/frostfs_testlib/shell/interfaces.py

@@ -22,11 +22,12 @@ class CommandInspector(ABC):
     """Interface of inspector that processes command text before execution."""
 
     @abstractmethod
-    def inspect(self, command: str) -> str:
+    def inspect(self, original_command: str, command: str) -> str:
         """Transforms command text and returns modified command.
 
         Args:
             command: Command to transform with this inspector.
+            original_command: Untransformed command to transform with this inspector. Depending on type of the inspector it might be required to modify original command
 
         Returns:
             Transformed command text.
@@ -47,6 +48,7 @@ class CommandOptions:
         check: Controls whether to check return code of the command. Set to False to
             ignore non-zero return codes.
         no_log: Do not print output to logger if True.
+        extra_inspectors: Exctra command inspectors to process command
     """
 
     interactive_inputs: Optional[list[InteractiveInput]] = None
@@ -54,6 +56,7 @@ class CommandOptions:
     timeout: Optional[int] = None
     check: bool = True
     no_log: bool = False
+    extra_inspectors: Optional[list[CommandInspector]] = None
 
     def __post_init__(self):
         if self.timeout is None:

src/frostfs_testlib/shell/local_shell.py

@@ -24,8 +24,10 @@ class LocalShell(Shell):
         # If no options were provided, use default options
         options = options or CommandOptions()
 
-        for inspector in self.command_inspectors:
-            command = inspector.inspect(command)
+        original_command = command
+        extra_inspectors = options.extra_inspectors if options.extra_inspectors else []
+        for inspector in [*self.command_inspectors, *extra_inspectors]:
+            command = inspector.inspect(original_command, command)
 
         logger.info(f"Executing command: {command}")
         if options.interactive_inputs:

src/frostfs_testlib/shell/ssh_shell.py

@@ -126,8 +126,10 @@ class SSHShell(Shell):
     def exec(self, command: str, options: Optional[CommandOptions] = None) -> CommandResult:
         options = options or CommandOptions()
 
-        for inspector in self.command_inspectors:
-            command = inspector.inspect(command)
+        original_command = command
+        extra_inspectors = options.extra_inspectors if options.extra_inspectors else []
+        for inspector in [*self.command_inspectors, *extra_inspectors]:
+            command = inspector.inspect(original_command, command)
 
         if options.interactive_inputs:
             result = self._exec_interactive(command, options)