Added the error handler module and the necessary changes to incorpora…

micado_eec/error_handler.py

@@ -0,0 +1,122 @@
+import io 
+from functools import wraps
+
+from enum import Enum
+
+class ErrorMessages(Enum):
+
+    ADT = ("U101", "There are error(s) in the generated ADT.")
+    ID = ("U102", "The provided ID(s) are not correct.")
+    PARAM = ("U103","There are error(s) in the parameter definition.")
+    INPUT = ("U104", "Malformed input.") 
+    IP = ("S101", "Floating IPs are not available.")
+
+
+class MicadoBuildException(Exception):
+    def __init__(self, message):
+        self.message = message
+
+class MicadoInfraException(Exception):
+    def __init__(self, message):
+        self.message = message
+
+
+class MicadoAppException(Exception):
+    def __init__(self, message):
+        self.message = message
+
+
+def handle_error(error_handler, final_task_handler = None, configs = None):
+    """This is the base method for handling the exceptions."""
+    def decorator(function):
+        @wraps(function)
+        def wrapper(*args, **kwargs):
+            try:
+                function(*args, **kwargs)
+            except Exception as e:
+                error_handler(e, configs, *args, **kwargs)
+            finally:
+                if final_task_handler is not None:
+                    final_task_handler(configs, *args, **kwargs)
+        return wrapper
+    return decorator
+
+
+def handle_node_data_error(e, configs, *args, **kwargs):
+    """Handles the errors generated while setting the MiCADO node data."""
+    if isinstance(e, AttributeError):
+        args[0].node_data = ""
+    else:
+        raise e
+
+
+def handle_create_node_error(e, configs, *args, **kwargs):
+    """Handles the error while creating a MiCADO node."""
+    threadID = args[0].threadID
+    r = configs["redis_conn"]
+
+    r.expire(threadID, 90)
+    args[0].status_detail = str(e)
+    args[0].status = configs["status"]
+    args[0].set_status()
+    raise e
+
+
+def handle_submit_app_final_task(configs, *args, **kwargs):
+    """This method closes the stream opened for a MiCADO application submission."""
+    app_data = args[1]
+    if isinstance(app_data, io.TextIOWrapper):
+        app_data.close()
+
+
+
+def handle_submit_app_error(e, configs, *args, **kwargs):
+    """Handles the error(s) while submitting an application."""
+
+    threadID = args[0].threadID
+    r = configs["redis_conn"]
+    STATUS_ERROR = configs["status"]
+
+    r.expire(threadID, 90)
+    args[0].status = STATUS_ERROR
+    args[0]._kill_micado(msg=str(e))
+    raise e
+
+
+
+def handle_attach_to_existing_error(e, configs, *args, **kwargs):
+    """Handles the error(s) while attaching MiCADO belonging to the thread ID"""
+
+    if isinstance(e, LookupError):
+        threadID = args[0].threadID
+        r = configs["redis_conn"]
+        r.delete(threadID)
+
+    raise e
+
+
+def handle_kill_micado_error(e, configs, *args, **kwargs):
+    """Handles the error(s) while removing a MiCADO node."""
+
+    STATUS_ERROR = configs["status"]
+    STATUS_INFRA_REMOVE_ERROR = configs["status_detail"]
+    if len(args)>1:
+        msg = args[1]
+    else:
+        msg = None
+
+    args[0].status = STATUS_ERROR
+    args[0].status_detail = msg or STATUS_INFRA_REMOVE_ERROR
+    args[0].set_status()
+    raise e
+
+
+def handle_valid_input_error(e, configs, *args, **kwargs):
+    """Handles the error(s) while checking the input."""
+
+    input_to_check = args[1]
+    if isinstance(e, KeyError):
+        error_message = " ".join(ErrorMessages.INPUT.value)
+        raise MicadoBuildException(f"{error_message} {input_to_check}")
+    else:
+        raise e