Merge pull request #192 from johnbywater/feature/tuple_transcoding

Added support for encoding tuples (and named tuples) as such.

docs/topics/notifications.rst

@@ -962,10 +962,9 @@ The library class :class:`~eventsourcing.interface.notificationlog.NotificationL
 presents sections from a local notification log, and can be used to implement a Web API.
 
 The :class:`~eventsourcing.interface.notificationlog.NotificationLogView`
-class is constructed with a local ``notification_log`` object and an optional
-``json_encoder_class`` (which defaults to the library's
-:class:`~eventsourcing.utils.transcoding.ObjectJSONEncoder` class, used explicitly
-in the example below).
+class is constructed with a local ``notification_log`` object and a
+``json_encoder`` (for example an instance of the library's
+:class:`~eventsourcing.utils.transcoding.ObjectJSONEncoder` class).
 
 The example below uses the record notification log, constructed above.
 
@@ -978,12 +977,12 @@ The example below uses the record notification log, constructed above.
 
     view = NotificationLogView(
         notification_log=notification_log,
-        json_encoder_class=ObjectJSONEncoder
+        json_encoder=ObjectJSONEncoder()
     )
 
     section_json, is_archived = view.present_section('1,5')
 
-    section_dict = json.loads(section_json, cls=ObjectJSONDecoder)
+    section_dict = ObjectJSONDecoder().decode(section_json)
 
     assert section_dict['section_id'] == '1,5'
     assert section_dict['next_id'] == '6,10'

eventsourcing/application/process.py

@@ -9,7 +9,6 @@
 from eventsourcing.exceptions import CausalDependencyFailed, PromptFailed
 from eventsourcing.infrastructure.base import ACIDRecordManager
 from eventsourcing.infrastructure.eventsourcedrepository import EventSourcedRepository
-from eventsourcing.utils.transcoding import json_dumps, json_loads
 
 
 class ProcessEvent(object):
@@ -151,7 +150,8 @@ def run(self, prompt=None, advance_by=None):
                     causal_dependencies = (
                         notification.get("causal_dependencies") or "[]"
                     )
-                    causal_dependencies = json_loads(causal_dependencies) or []
+                    causal_dependencies = self.event_store.mapper.json_loads(
+                        causal_dependencies) or []
 
                     # Check causal dependencies are satisfied.
                     for causal_dependency in causal_dependencies:
@@ -454,7 +454,8 @@ def construct_event_records(self, pending_events, causal_dependencies=None):
                 assert hasattr(
                     self.event_store.record_manager.record_class, "causal_dependencies"
                 )
-                causal_dependencies = json_dumps(causal_dependencies)
+                causal_dependencies = self.event_store.mapper.json_dumps(
+                    causal_dependencies)
                 # Only need first event to carry the dependencies.
                 event_records[0].causal_dependencies = causal_dependencies
 

eventsourcing/application/system.py

@@ -564,7 +564,8 @@ def loop_on_prompts(self):
         # Loop on getting prompts.
         while True:
             try:
-                # Todo: Make the poll interval gradually increase if there are only timeouts?
+                # Todo: Make the poll interval gradually
+                #  increase if there are only timeouts?
                 prompt = self.inbox.get(timeout=self.poll_interval)
 
             except Empty:

eventsourcing/domain/model/events.py

@@ -5,7 +5,7 @@
 from eventsourcing.utils.hashing import hash_object
 from eventsourcing.utils.times import decimaltimestamp
 from eventsourcing.utils.topic import get_topic
-from eventsourcing.utils.transcoding import ObjectJSONEncoder
+from eventsourcing.utils.transcoding import JSON_SEPARATORS, ObjectJSONEncoder
 
 GENESIS_HASH = os.getenv("GENESIS_HASH", "")
 
@@ -26,7 +26,7 @@ class DomainEvent(object):
     of the state of the event.
     """
 
-    __json_encoder_class__ = ObjectJSONEncoder
+    __json_encoder__ = ObjectJSONEncoder(separators=JSON_SEPARATORS)
     __notifiable__ = True
 
     def __init__(self, **kwargs):
@@ -128,7 +128,7 @@ def __hash_object__(cls, obj):
         :return: SHA-256 as hexadecimal string.
         :rtype: str
         """
-        return hash_object(cls.__json_encoder_class__, obj)
+        return hash_object(cls.__json_encoder__, obj)
 
 
 class EventWithHash(DomainEvent):

eventsourcing/infrastructure/eventstore.py

@@ -54,7 +54,8 @@ def all_domain_events(self):
         """
 
 
-# Todo: Unify iterators in EventStore and in NotificationLog, by pushing behaviour down to record manager?
+# Todo: Unify iterators in EventStore and in NotificationLog,
+#  by pushing behaviour down to record manager?
 
 
 class EventStore(AbstractEventStore):

eventsourcing/infrastructure/sequenceditemmapper.py

@@ -1,6 +1,7 @@
 from __future__ import unicode_literals
 
 from abc import ABC, abstractmethod
+from json import JSONDecodeError
 
 from eventsourcing.infrastructure.sequenceditem import (
     SequencedItem,
@@ -10,9 +11,7 @@
 from eventsourcing.utils.transcoding import (
     ObjectJSONDecoder,
     ObjectJSONEncoder,
-    json_dumps,
-    json_loads,
-)
+    JSON_SEPARATORS)
 
 
 class AbstractSequencedItemMapper(ABC):
@@ -28,6 +27,18 @@ def event_from_item(self, sequenced_item):
         Constructs and returns a domain event for given sequenced item.
         """
 
+    @abstractmethod
+    def json_dumps(self, event_attrs):
+        """
+        Encodes given object as JSON.
+        """
+
+    @abstractmethod
+    def json_loads(self, event_attrs):
+        """
+        Decodes given JSON as object.
+        """
+
 
 class SequencedItemMapper(AbstractSequencedItemMapper):
     """
@@ -46,7 +57,10 @@ def __init__(
     ):
         self.sequenced_item_class = sequenced_item_class
         self.json_encoder_class = json_encoder_class or ObjectJSONEncoder
+        self.json_encoder = self.json_encoder_class(separators=JSON_SEPARATORS,
+                                                    sort_keys=True)
         self.json_decoder_class = json_decoder_class or ObjectJSONDecoder
+        self.json_decoder = self.json_decoder_class()
         self.cipher = cipher
         self.field_names = SequencedItemFieldNames(self.sequenced_item_class)
         self.sequence_id_attr_name = (
@@ -91,14 +105,17 @@ def get_item_topic_and_state(self, domain_event_class, event_attrs):
         topic = get_topic(domain_event_class)
 
         # Serialise the event attributes.
-        state = json_dumps(event_attrs, cls=self.json_encoder_class)
+        state = self.json_dumps(event_attrs)
 
-        # Encrypt serialised state.
+        # Compress and encrypt serialised state.
         if self.cipher:
             state = self.cipher.encrypt(state)
 
         return topic, state
 
+    def json_dumps(self, event_attrs):
+        return self.json_encoder.encode(event_attrs)
+
     def construct_sequenced_item(self, item_args):
         return self.sequenced_item_class(*item_args)
 
@@ -128,14 +145,21 @@ def get_event_class_and_attrs(self, topic, state):
         # Resolve topic to event class.
         domain_event_class = resolve_topic(topic)
 
-        # Decrypt state.
+        # Decrypt and decompress state.
         if self.cipher:
             state = self.cipher.decrypt(state)
 
         # Deserialize data.
-        event_attrs = json_loads(state, cls=self.json_decoder_class)
+        event_attrs = self.json_loads(state)
         return domain_event_class, event_attrs
 
+    def json_loads(self, state):
+        try:
+            return self.json_decoder.decode(state)
+        except JSONDecodeError:
+            raise ValueError("Couldn't load JSON string: {}".format(s))
+
+
 
 def reconstruct_object(obj_class, obj_state):
     obj = object.__new__(obj_class)

eventsourcing/interface/notificationlog.py

@@ -1,27 +1,19 @@
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-import json
+from json import JSONDecodeError
 
 import requests
 
 from eventsourcing.application.notificationlog import (
-    Section,
     AbstractNotificationLog,
     LocalNotificationLog,
-)
-from eventsourcing.utils.transcoding import (
-    ObjectJSONDecoder,
-    ObjectJSONEncoder,
-    json_dumps,
-)
+    Section,
+    RecordManagerNotificationLog)
+from eventsourcing.utils.transcoding import ObjectJSONDecoder
 
 
 # These classes are imported here only to avoid breaking backwards compatibility.
 # Todo: Remove this import statement >= v8.x
-from eventsourcing.application.notificationlog import (
-    RecordManagerNotificationLog,
-    BigArrayNotificationLog,
-)
 
 
 class RemoteNotificationLog(AbstractNotificationLog):
@@ -36,10 +28,17 @@ def __init__(self, base_url, json_decoder_class=None):
         Initialises remote notification log object.
 
         :param str base_url: A URL for the HTTP API.
-        :param JSONDecoder json_decoder_class: JSON decoder class used to decode remote sections.
+        :param JSONDecoder json_decoder_class: used to deserialize remote sections.
         """
         self.base_url = base_url
-        self.json_decoder_class = json_decoder_class
+        json_decoder_class = json_decoder_class or ObjectJSONDecoder
+        self.json_decoder = json_decoder_class()
+
+    def json_loads(self, value: str):
+        try:
+            return self.json_decoder.decode(value)
+        except JSONDecodeError:
+            raise ValueError("Couldn't load JSON string: {}".format(value))
 
     def __getitem__(self, section_id):
         """
@@ -54,8 +53,7 @@ def __getitem__(self, section_id):
 
     def deserialize_section(self, section_json):
         try:
-            decoder_class = self.json_decoder_class or ObjectJSONDecoder
-            section = Section(**json.loads(section_json, cls=decoder_class))
+            section = Section(**self.json_loads(section_json))
         except ValueError as e:
             raise ValueError(
                 "Couldn't deserialize notification log section: "
@@ -85,7 +83,7 @@ class NotificationLogView(object):
     remotely, for example by a RemoteNotificationLog.
     """
 
-    def __init__(self, notification_log: LocalNotificationLog, json_encoder_class=None):
+    def __init__(self, notification_log: RecordManagerNotificationLog, json_encoder):
         """
         Initialises notification log view object.
 
@@ -96,7 +94,7 @@ def __init__(self, notification_log: LocalNotificationLog, json_encoder_class=No
             notification_log
         )
         self.notification_log = notification_log
-        self.json_encoder_class = json_encoder_class or ObjectJSONEncoder
+        self.json_encoder = json_encoder
 
     def present_section(self, section_id):
         """
@@ -110,5 +108,5 @@ def present_section(self, section_id):
         """
         section = self.notification_log[section_id]
         is_archived = bool(section.next_id)
-        section_json = json_dumps(section.__dict__, self.json_encoder_class)
+        section_json = self.json_encoder.encode(section.__dict__)
         return section_json, is_archived

eventsourcing/tests/contrib_tests/paxos_tests/test_paxos_system.py

@@ -14,7 +14,7 @@
     clear_event_handlers,
 )
 from eventsourcing.tests.base import notquick
-from eventsourcing.tests.test_system_fixtures import set_db_uri
+from eventsourcing.tests.system_test_fixtures import set_db_uri
 
 
 class TestPaxosSystem(unittest.TestCase):

eventsourcing/tests/test_system_fixtures.py → eventsourcing/tests/system_test_fixtures.py

@@ -1,5 +1,6 @@
 import logging
 import os
+from uuid import uuid5, NAMESPACE_OID
 
 from eventsourcing.application.process import ProcessApplication
 from eventsourcing.domain.model.aggregate import BaseAggregateRoot
@@ -62,7 +63,14 @@ class Created(Event, BaseAggregateRoot.Created):
 
     @classmethod
     def create(cls, order_id):
-        return cls.__create__(order_id=order_id)
+        return cls.__create__(
+            originator_id=Reservation.create_reservation_id(order_id),
+            order_id=order_id
+        )
+
+    @classmethod
+    def create_reservation_id(cls, order_id):
+        return uuid5(NAMESPACE_OID, str(order_id))
 
 
 class Payment(BaseAggregateRoot):
@@ -114,6 +122,7 @@ def policy(repository, event):
 
 
 class Reservations(ProcessApplication):
+
     @staticmethod
     def policy(repository, event):
         if isinstance(event, Order.Created):

eventsourcing/tests/test_actors.py

@@ -16,7 +16,7 @@
     assert_event_handlers_empty,
     clear_event_handlers,
 )
-from eventsourcing.tests.test_system_fixtures import (
+from eventsourcing.tests.system_test_fixtures import (
     Orders,
     Payments,
     Reservations,

eventsourcing/tests/test_notificationlog.py

@@ -24,6 +24,7 @@
     SQLAlchemyRecordManagerTestCase,
 )
 from eventsourcing.utils.topic import get_topic
+from eventsourcing.utils.transcoding import ObjectJSONEncoder, JSON_SEPARATORS
 
 
 class NotificationLogTestCase(SQLAlchemyRecordManagerTestCase, WithEventPersistence):
@@ -283,7 +284,8 @@ def simple_app(environ, start_response):
             notification_log = self.create_notification_log(section_size)
 
             # Get serialized section.
-            view = NotificationLogView(notification_log)
+            json_encoder = ObjectJSONEncoder(separators=JSON_SEPARATORS)
+            view = NotificationLogView(notification_log, json_encoder)
             section, is_archived = view.present_section(section_id)
             # Todo: Maybe redirect if the section ID is a mismatch, so
             # the URL is good for cacheing.

eventsourcing/tests/test_process.py

@@ -25,7 +25,7 @@
 from eventsourcing.exceptions import CausalDependencyFailed, PromptFailed
 from eventsourcing.infrastructure.sqlalchemy.records import Base
 from eventsourcing.utils.topic import resolve_topic
-from eventsourcing.utils.transcoding import json_loads
+from eventsourcing.utils.transcoding import ObjectJSONDecoder
 
 
 class TestProcessApplication(TestCase):
@@ -164,7 +164,7 @@ def test_causal_dependencies(self):
 
         # - the second 'Created' event depends on the Created event in another pipeline.
         expect = [{"notification_id": 1, "pipeline_id": pipeline_id1}]
-        actual = json_loads(second_entity_records[0].causal_dependencies)
+        actual = ObjectJSONDecoder().decode(second_entity_records[0].causal_dependencies)
 
         self.assertEqual(expect, actual)