Region adjustment

STACKIT will move to a new way of specifying regions, where the region is provided
as a function argument instead of being set in the client configuration.
Once all services have migrated, the methods to specify the region in the client
configuration will be removed.

Signed-off-by: Alexander Dahmen <alexander.dahmen@inovex.de>

Author: Fyusel

templates/python/configuration.mustache

@@ -8,6 +8,10 @@ class HostConfiguration:
                  server_operation_index=None, server_operation_variables=None,
                  ignore_operation_servers=False,
                  ) -> None:
+        print("WARNING: STACKIT will move to a new way of specifying regions, where the region is provided\n",
+        "as a function argument instead of being set in the client configuration.\n"
+        "Once all services have migrated, the methods to specify the region in the client configuration "
+        "will be removed.")
         """Constructor
         """
         self._base_path = "{{{basePath}}}"
@@ -67,6 +71,7 @@ class HostConfiguration:
         :param index: array index of the host settings
         :param variables: hash of variable and the corresponding value
         :param servers: an array of host settings or None
+        :error: if a region is given for a global url
         :return: URL based on host settings
         """
         if index is None:
@@ -84,8 +89,23 @@ class HostConfiguration:
 
         url = server['url']
 
+        # check if environment variable was provided for region
+        # if nothing was set this is None
+        region_env = os.environ.get("STACKIT_REGION")
+
         # go through variables and replace placeholders
         for variable_name, variable in server.get('variables', {}).items():
+            # If a region is provided by the user for a global url
+            # return an error (except for providing via environment variable).
+            # The region is provided as a function argument instead of being set in the client configuration.
+            if variable_name == 'region' and \
+               (variable['default_value'] == 'global' or variable['default_value'] == '') and \
+               region_env is None and \
+               variables.get(variable_name) is not None:
+                    raise ValueError(
+                        "this API does not support setting a region in the the client configuration, "
+                        "please check if the region can be specified as a function parameter"
+                    )
             used_value = variables.get(
                 variable_name, variable['default_value'])