munet: Configurable environment variables within Linux Namespace nodes

munet/base.py

@@ -1204,6 +1204,7 @@
         new_window=False,
         tmux_target=None,
         ns_only=False,
+        env_vars=None,
     ):
         """Run a command in a new window (TMUX, Screen or XTerm).
 
@@ -1217,6 +1218,7 @@
             forcex: Force use of X11.
             new_window: Open new window (instead of pane) in TMUX
             tmux_target: Target for tmux pane.
+            env_vars: Dict of extra env variables to set in the window
 
         Returns:
             the pane/window identifier from TMUX (depends on `new_window`)
@@ -1228,6 +1230,9 @@
             channel = "{}-wait-{}".format(our_pid, Commander.tmux_wait_gen)
             Commander.tmux_wait_gen += 1
 
+        if not isinstance(env_vars, dict):
+            env_vars = {}
+
         if forcex or ("TMUX" not in os.environ and "STY" not in os.environ):
             root_level = False
         else:
@@ -1249,8 +1254,11 @@
                 cmd = shlex.split(cmd)
             cmd = [
                 "/usr/bin/env",
-                f"MUNET_NODENAME={self.name}",
             ]
+            # Set extra env variables first so that they will be overwritted if needed
+            for key, value in env_vars:
+                cmd.append(f"{key}={shell_quote(value)}")
+            cmd.append(f"MUNET_NODENAME={self.name}")
             if "MUNET_PID" in os.environ:
                 cmd.append(f"MUNET_PID={os.environ.get('MUNET_PID')}")
             cmd += cmd
@@ -1269,8 +1277,12 @@
             ]
         else:
             # This is the command to execute to be inside the namespace.
+            # Set extra env variables first so that they will be overwritted if needed
+            envvars = ""
+            for key, value in env_vars.items():
+                envvars += f' {key}={shell_quote(value)}'
             # We are getting into trouble with quoting.
-            envvars = f"MUNET_NODENAME={self.name} NODENAME={self.name}"
+            envvars += f" MUNET_NODENAME={self.name} NODENAME={self.name}"
             if hasattr(self, "rundir"):
                 envvars += f" RUNDIR={self.rundir}"
             if "MUNET_PID" in os.environ:

munet/native.py

@@ -1231,16 +1231,74 @@
 class L3NamespaceNode(L3NodeMixin, LinuxNamespace):
     """A namespace L3 node."""
 
-    def __init__(self, name, pid=True, **kwargs):
+    def __init__(self, name, pid=True, config=None, **kwargs):
         # logging.warning(
         #     "L3NamespaceNode: name %s MRO: %s kwargs %s",
         #     name,
         #     L3NamespaceNode.mro(),
         #     kwargs,
         # )
-        super().__init__(name, pid=pid, **kwargs)
+        self.config = config if config else {}
+        super().__init__(name, pid=pid, config=config, **kwargs)
         super().pytest_hook_open_shell()
 
+    def _get_sub_args(self, cmd_list, defaults, use_pty=False, ns_only=False, **kwargs):
+        """Returns pre-command, cmd, and default keyword args.
+
+        Overrides Commander in order to insert configured enviornmental variables
+        """
+        pre_cmd_list, cmd_list, defaults = super()._get_sub_args(
+            cmd_list, defaults, use_pty, ns_only, **kwargs
+        )
+
+        if self.config and "env" in self.config and self.config["env"]:
+            config_env = {}
+            for env_var in self.config["env"].items():
+                config_env[env_var[0]] = env_var[1]["value"]
+
+            # All values in defaults should NOT be overwritten by config_env
+            config_env.update(defaults["env"])
+            defaults["env"] = config_env
+
+        return pre_cmd_list, cmd_list, defaults
+
+    def run_in_window(  # pylint: disable=too-many-positional-arguments
+        self,
+        cmd,
+        wait_for=False,
+        background=False,
+        name=None,
+        title=None,
+        forcex=False,
+        new_window=False,
+        tmux_target=None,
+        ns_only=False,
+        env_vars=None,
+    ):
+
+        if self.config and "env" in self.config and self.config["env"]:
+            config_env = {}
+            for env_var in self.config["env"].items():
+                config_env[env_var[0]] = env_var[1]["value"]
+
+            if isinstance(env_vars, dict):
+                # All values in defaults should NOT be overwritten by config_env
+                config_env.update(env_vars)
+            env_vars=config_env
+
+        super().run_in_window(
+            cmd,
+            wait_for,
+            background,
+            name,
+            title,
+            forcex,
+            new_window,
+            tmux_target,
+            ns_only,
+            env_vars,
+        )
+
     async def _async_delete(self):
         self.logger.debug("%s: deleting", self)
         await super()._async_delete()

tests/mutest_after/env_vars/munet.yaml

@@ -0,0 +1,11 @@
+
+topology:
+  nodes:
+    - name: r1
+      cmd: |
+        echo $foo0
+      env:
+      - name: foo0
+        value: bar
+      - name: foo1
+        value: 'bar ''" baz'

tests/mutest_after/env_vars/mutest_config_env.py

@@ -0,0 +1,42 @@
+# -*- coding: utf-8 eval: (blacken-mode 1) -*-
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# April 18 2025, Liam Brady <[email protected]>
+#
+# Copyright (c) 2022, LabN Consulting, L.L.C.
+#
+"""Test for config of env variables.
+
+This test is for ensuring that configured environment variables properly appear
+within run commands.
+"""
+import munet
+from munet.mutest.userapi import match_step
+from munet.mutest.userapi import section
+
+# Configured environment variables also should be set within
+# new munet windows, however, this is not tested here.
+
+section("Test config for env variables")
+
+match_step(
+    "r1",
+    "cat cmd.out",
+    "bar",
+    "Check for env variable in cmd.out",
+    exact_match=True,
+)
+match_step(
+    "r1",
+    "echo $foo0",
+    "bar",
+    "Check for env variable in Linux namespace",
+    exact_match=True,
+)
+match_step(
+    "r1",
+    "echo $foo1",
+    "bar '\" baz",
+    "Check env variable for proper quoting",
+    exact_match=True,
+)