Merge pull request #7 from aotuai/server_error

Add new ServerNotReadyError that handles 502s and requests exceptions

Author: BryceBeagle

brainframe/api/bf_errors.py

@@ -1,19 +1,19 @@
 import re
 from typing import Optional
 
-
 kind_to_error_type = {}
 """Maps error kinds to their corresponding error type."""
 
 
-def _register_error(kind: Optional[str] = None):
+def _server_origin_error(kind: Optional[str] = None):
     """A class decorator. Registers the given class so that it will be used
     when an error with a kind equal to the class's name is provided as a
-    response.
+    response. Used only for Errors that can originate on the BrainFrame server.
 
     :param kind: If provided, this class will be associated with this kind
         instead of using the class's name as the kind
     """
+
     def wrapper(cls):
         global kind_to_error_type
         nonlocal kind
@@ -47,7 +47,7 @@ def pretty_name(self):
         return s3
 
 
-@_register_error()
+@_server_origin_error()
 class UnknownError(BaseAPIError):
     """Something unexpected happened. The server may be in an invalid state."""
 
@@ -56,237 +56,242 @@ def __init__(self, description, status_code=None):
         self.status_code = status_code
 
 
-@_register_error()
+@_server_origin_error()
 class StreamConfigNotFoundError(BaseAPIError):
     """A StreamConfiguration specified by the client could not be found."""
 
 
-@_register_error()
+@_server_origin_error()
 class ZoneNotFoundError(BaseAPIError):
     """A Zone specified by the client could not be found."""
 
 
-@_register_error()
+@_server_origin_error()
 class PremisesNotFoundError(BaseAPIError):
     """A Zone specified by the client could not be found."""
 
 
-@_register_error()
+@_server_origin_error()
 class ZoneNotDeletableError(BaseAPIError):
     """A client tried to delete a default Zone"""
 
 
-@_register_error()
+@_server_origin_error()
 class AlertNotFoundError(BaseAPIError):
     """An Alert specified by the client could not be found."""
 
 
-@_register_error()
+@_server_origin_error()
 class InvalidSyntaxError(BaseAPIError):
     """The syntax of the request could not be parsed."""
 
 
-@_register_error()
+@_server_origin_error()
 class InvalidFormatError(BaseAPIError):
     """The request was parsed, but some value within the request is invalid."""
 
 
-@_register_error("NotImplementedError")
+@_server_origin_error("NotImplementedError")
 class NotImplementedInAPIError(BaseAPIError):
     """The client requested something that is not currently implemented."""
 
 
-@_register_error()
+@_server_origin_error()
 class StreamNotOpenedError(BaseAPIError):
     """A stream failed to open when it was required to."""
 
 
-@_register_error()
+@_server_origin_error()
 class DuplicateStreamSourceError(BaseAPIError):
     """There was an attempted to create a stream configuration with the same
     source as an existing one.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class DuplicateZoneNameError(BaseAPIError):
     """There was an attempt to make a zone with the same name as another zone
     within the same stream.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class DuplicateIdentityNameError(BaseAPIError):
     """There was an attempt to create a new identity with the same name as
     another identity.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class NoDetectorForClassError(BaseAPIError):
     """There was an attempt to use a class name that is not detectable."""
 
 
-@_register_error()
+@_server_origin_error()
 class NoEncoderForClassError(BaseAPIError):
     """There was an attempt to create an identity for a class that is not
     encodable.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class IdentityNotFoundError(BaseAPIError):
     """An identity specified by the client could not be found."""
 
 
-@_register_error()
+@_server_origin_error()
 class ImageNotFoundForIdentityError(BaseAPIError):
     """An image specified by the client could not be found for the specified
     identity.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class InvalidImageTypeError(BaseAPIError):
     """An image could not be decoded by OpenCV"""
 
 
-@_register_error()
+@_server_origin_error()
 class AnalysisLimitExceededError(BaseAPIError):
     """There was an attempt to start analysis on a stream, but the maximum
     amount of streams that may have analysis run on them at once has already
     been reached.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class NoDetectionsInImageError(BaseAPIError):
     """There was an attempt to encode an image with no objects of the given
     class in the frame.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class TooManyDetectionsInImageError(BaseAPIError):
     """There was an attempt to encode an image with more than one object of the
     given class in the frame, causing ambiguity on which one to encode.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class ImageAlreadyEncodedError(BaseAPIError):
     """There was an attempt to encode an image that has already been encoded
     for a given identity and a given class.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class DuplicateVectorError(BaseAPIError):
     """There was an attempt to add a vector that already exists for the given
     identity and class.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class FrameNotFoundForAlertError(BaseAPIError):
     """There was an attempt to get a frame for an alert that has no frame."""
 
 
-@_register_error("PluginNotFoundError")
+@_server_origin_error("PluginNotFoundError")
 class CapsuleNotFoundError(BaseAPIError):
     """There was an attempt to reference a capsule that does not exist."""
 
 
-@_register_error("InvalidPluginOptionError")
+@_server_origin_error("InvalidPluginOptionError")
 class InvalidCapsuleOptionError(BaseAPIError):
     """The provided capsule options do not work for the given capsule. This
     could be because the option does not exist or the value for that option
     doesn't fit the constraints.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class StorageNotFoundError(BaseAPIError):
     """There was an attempt to access a storage object that does not exist."""
 
 
-@_register_error()
+@_server_origin_error()
 class ZoneAlarmNotFoundError(BaseAPIError):
     """There was an attempt to access a zone alarm that does not exist."""
 
 
-@_register_error()
+@_server_origin_error()
 class InvalidRuntimeOptionError(BaseAPIError):
     """There was an attempt to set a runtime option that is not supported or is
     of the wrong type.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class EncodingNotFoundError(BaseAPIError):
     """There was an attempt to access an encoding that does not exist."""
 
 
-@_register_error()
+@_server_origin_error()
 class UnauthorizedError(BaseAPIError):
     """There was an attempt to access the API without proper authorization."""
 
 
-@_register_error()
+@_server_origin_error()
 class InvalidSessionError(BaseAPIError):
     """There was an attempt to access the API with an invalid session ID,
     either because the session expired or no session with that ID has ever
     existed. The client should authenticate again to get a new session.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class VectorTooLongError(BaseAPIError):
     """The provided encoding vector is longer than the maximum allowed
     length.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class UserNotFoundError(BaseAPIError):
     """There was an attempt to access a user by ID that does not exist."""
 
 
-@_register_error()
+@_server_origin_error()
 class InsufficientRoleError(BaseAPIError):
     """A user attempted an operation that they don't have permission to do."""
 
 
-@_register_error()
+@_server_origin_error()
 class DuplicateUsernameError(BaseAPIError):
     """The requested username already exists."""
 
 
-@_register_error()
+@_server_origin_error()
 class AdminMustExistError(BaseAPIError):
     """There was an attempt to delete the only remaining admin account."""
 
 
-@_register_error()
+@_server_origin_error()
 class LicenseRequiredError(BaseAPIError):
     """There was an attempt to access a resource that requires an active
     license while no valid license is loaded.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class LicenseExpiredError(BaseAPIError):
     """There was an attempt to upload a license that is expired."""
 
 
-@_register_error()
+@_server_origin_error()
 class LicenseInvalidError(BaseAPIError):
     """There was an attempt to upload a license that is in an invalid format.
     """
 
 
-@_register_error()
+@_server_origin_error()
 class RemoteConnectionError(BaseAPIError):
     """The server encountered an error while connecting to a remote resource
     that is required for the requested operation.
     """
+
+
+class ServerNotReadyError(BaseAPIError):
+    """The client was able to communicate with the server, but the server had
+    not completed startup or was in an invalid state"""

brainframe/api/status_receiver.py

@@ -3,10 +3,7 @@
 from time import sleep
 from typing import Any, Callable, Dict, List, Optional
 
-import requests
-
-from .bf_errors import UnknownError
-from .bf_codecs import ZoneStatus
+from . import bf_codecs, bf_errors
 from .stubs.zone_statuses import ZONE_STATUS_STREAM_TYPE, ZONE_STATUS_TYPE
 
 
@@ -53,7 +50,8 @@ def add_listener(self, listener: Callable[[ZONE_STATUS_TYPE], Any]):
     def is_running(self) -> bool:
         return self._running
 
-    def latest_statuses(self, stream_id: int) -> Dict[str, ZoneStatus]:
+    def latest_statuses(self, stream_id: int) \
+            -> Dict[str, bf_codecs.ZoneStatus]:
         """Returns the latest cached list of ZoneStatuses for that stream_id,
         or any empty dict if none are cached"""
         return self._latest_statuses.get(stream_id, {})
@@ -83,15 +81,7 @@ def _run(self):
                     timeout=self._ZONE_STATUS_STREAM_TIMEOUT)
             try:
                 zone_statuses = next(zone_status_stream)
-            except (StopIteration,
-                    requests.exceptions.RequestException,
-                    UnknownError) as ex:
-
-                # Catch any 502 errors that happen during server restart
-                if isinstance(ex, UnknownError) \
-                        and ex.status_code != 502:
-                    raise
-
+            except (StopIteration, bf_errors.ServerNotReadyError) as ex:
                 if not self._running:
                     break