[rqd] Feature: RQD use host env vars (#1324)

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**Summarize your change.**
Based on `RQD_USE_PATH_ENV_VAR` but generalized to any host env var.

---------

Signed-off-by: Diego Tavares <[email protected]>
Co-authored-by: Diego Tavares <[email protected]>

Author: Tilix4

rqd/rqd/rqconstants.py

@@ -72,6 +72,14 @@
 # Copy specific environment variable from the RQD host to the frame env.
 RQD_HOST_ENV_VARS = []
 
+# Use the environment variables from the RQD host. For variables that exist
+# In cases where a variable exists on both the host and the frame object (which are
+# copied during initialization), the value from the host will take precedence.
+# However, the handling of the PATH variable is unique: its value from the frame
+# is merged with the host's value, with the frame's value taking precedence in the
+# final result. If any var is defined at RQD_HOST_ENV_VARS, this attribute is considered False.
+RQD_USE_ALL_HOST_ENV_VARS = False
+
 RQD_CUSTOM_HOME_PREFIX = None
 RQD_CUSTOM_MAIL_PREFIX = None
 
@@ -219,6 +227,9 @@
                                                          "RQD_USE_IPV6_AS_HOSTNAME")
         if config.has_option(__override_section, "RQD_USE_PATH_ENV_VAR"):
             RQD_USE_PATH_ENV_VAR = config.getboolean(__override_section, "RQD_USE_PATH_ENV_VAR")
+        if config.has_option(__override_section, "RQD_USE_ALL_HOST_ENV_VARS"):
+            RQD_USE_HOST_ENV_VARS = config.getboolean(__override_section,
+                "RQD_USE_ALL_HOST_ENV_VARS")
         if config.has_option(__override_section, "RQD_BECOME_JOB_USER"):
             RQD_BECOME_JOB_USER = config.getboolean(__override_section, "RQD_BECOME_JOB_USER")
         if config.has_option(__override_section, "RQD_TAGS"):

rqd/rqd/rqcore.py

@@ -77,7 +77,6 @@ def __init__(self, optNimbyoff=False):
         self.nimby = rqd.rqnimby.NimbyFactory.getNimby(self)
 
         self.machine = rqd.rqmachine.Machine(self, self.cores)
-
         self.network = rqd.rqnetwork.Network(self)
         self.__threadLock = threading.Lock()
         self.__cache = {}
@@ -767,10 +766,18 @@ def __createEnvVariables(self):
             for variable in ["SYSTEMROOT", "APPDATA", "TMP", "COMMONPROGRAMFILES", "SYSTEMDRIVE"]:
                 if variable in os.environ:
                     self.frameEnv[variable] = os.environ[variable]
-        for variable in rqd.rqconstants.RQD_HOST_ENV_VARS:
-            # Fallback to empty string, easy to spot what is missing in the log
-            self.frameEnv[variable] = os.environ.get(variable, '')
-
+        if rqd.rqconstants.RQD_HOST_ENV_VARS:
+            for variable in rqd.rqconstants.RQD_HOST_ENV_VARS:
+                # Fallback to empty string, easy to spot what is missing in the log
+                self.frameEnv[variable] = os.environ.get(variable, '')
+        elif rqd.rqconstants.RQD_USE_ALL_HOST_ENV_VARS:
+            # Add host environment variables
+            for key, value in os.environ.items():
+                # Merge frame PATH with host PATH
+                if "PATH" == key and key in self.frameEnv:
+                    self.frameEnv[key] += os.pathsep + value
+                else:
+                    self.frameEnv[key] = value
         for key, value in self.runFrame.environment.items():
             if key == 'PATH':
                 self.frameEnv[key] += os.pathsep + value