accept ALLOWED_COMMANDS as alias of ALLOW_COMMANDS

Author: tumf

README.md

@@ -75,15 +75,17 @@ pip install mcp-shell-server
 
 ```bash
 ALLOW_COMMANDS="ls,cat,echo" uvx mcp-shell-server
+# Or using the alias
+ALLOWED_COMMANDS="ls,cat,echo" uvx mcp-shell-server
 ```
 
-The `ALLOW_COMMANDS` environment variable specifies which commands are allowed to be executed. Commands can be separated by commas with optional spaces around them.
+The `ALLOW_COMMANDS` (or its alias `ALLOWED_COMMANDS` ) environment variable specifies which commands are allowed to be executed. Commands can be separated by commas with optional spaces around them.
 
-Valid formats for ALLOW_COMMANDS:
+Valid formats for ALLOW_COMMANDS or ALLOWED_COMMANDS:
 
 ```bash
 ALLOW_COMMANDS="ls,cat,echo"          # Basic format
-ALLOW_COMMANDS="ls ,echo, cat"        # With spaces
+ALLOWED_COMMANDS="ls ,echo, cat"      # With spaces (using alias)
 ALLOW_COMMANDS="ls,  cat  , echo"     # Multiple spaces
 ```
 

src/mcp_shell_server/shell_executor.py

@@ -18,13 +18,15 @@ def __init__(self):
 
     def _get_allowed_commands(self) -> set:
         """
-        Get the set of allowed commands from environment variable.
-
-        Returns:
-            set: Set of allowed command names
+        Get the set of allowed commands from environment variables.
+        Checks both ALLOW_COMMANDS and ALLOWED_COMMANDS.
         """
         allow_commands = os.environ.get("ALLOW_COMMANDS", "")
-        return {cmd.strip() for cmd in allow_commands.split(",") if cmd.strip()}
+        allowed_commands = os.environ.get("ALLOWED_COMMANDS", "")
+
+        # Combine and deduplicate commands from both environment variables
+        commands = allow_commands + "," + allowed_commands
+        return {cmd.strip() for cmd in commands.split(",") if cmd.strip()}
 
     def _clean_command(self, command: List[str]) -> List[str]:
         """

tests/test_shell_executor.py

@@ -184,3 +184,39 @@ async def test_command_completes_within_timeout(executor, monkeypatch):
     assert result["error"] is None
     assert result["status"] == 0
     assert result["stdout"] == ""
+
+
+@pytest.mark.asyncio
+async def test_allowed_commands_alias(executor, monkeypatch):
+    """Test ALLOWED_COMMANDS alias functionality"""
+    monkeypatch.setenv("ALLOWED_COMMANDS", "echo")
+    result = await executor.execute(["echo", "hello"])
+    assert result["stdout"].strip() == "hello"
+    assert result["status"] == 0
+
+
+@pytest.mark.asyncio
+async def test_both_allow_commands_vars(executor, monkeypatch):
+    """Test both ALLOW_COMMANDS and ALLOWED_COMMANDS working together"""
+    monkeypatch.setenv("ALLOW_COMMANDS", "echo")
+    monkeypatch.setenv("ALLOWED_COMMANDS", "cat")
+
+    # Test command from ALLOW_COMMANDS
+    result1 = await executor.execute(["echo", "hello"])
+    assert result1["stdout"].strip() == "hello"
+    assert result1["status"] == 0
+
+    # Test command from ALLOWED_COMMANDS
+    result2 = await executor.execute(["cat"], stdin="world")
+    assert result2["stdout"].strip() == "world"
+    assert result2["status"] == 0
+
+
+@pytest.mark.asyncio
+async def test_allow_commands_precedence(executor, monkeypatch):
+    """Test that commands are combined from both environment variables"""
+    monkeypatch.setenv("ALLOW_COMMANDS", "echo,ls")
+    monkeypatch.setenv("ALLOWED_COMMANDS", "echo,cat")
+
+    allowed = executor.get_allowed_commands()
+    assert set(allowed) == {"echo", "ls", "cat"}