Merge pull request #72 from tarfin-labs/WEB-4286-event-machine-json-a…

…lanlarinin-boyutunu-azaltmak WEB-4286: Event Machine: Reducing the size of context field
tarfin-labs · Jan 8, 2024 · 225341d · 225341d
2 parents 1ce5b93 + 04ed0e0
commit 225341d
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Showing 2 changed files with 138 additions and 7 deletions.
diff --git a/src/Actor/Machine.php b/src/Actor/Machine.php
@@ -217,14 +217,37 @@ public function send(
      */
     public function persist(): ?State
     {
+        // Retrieve the previous context from the definition's config, or set it to an empty array if not set.
+        $incrementalContext = $this->definition->initializeContextFromState()->toArray();
+
+        // Get the last event from the state's history.
+        $lastHistoryEvent = $this->state->history->last();
+
         MachineEvent::upsert(
-            values: $this->state->history->map(fn (MachineEvent $machineEvent) => array_merge($machineEvent->toArray(), [
-                'created_at'    => $machineEvent->created_at->toDateTimeString(),
-                'machine_value' => json_encode($machineEvent->machine_value, JSON_THROW_ON_ERROR),
-                'payload'       => json_encode($machineEvent->payload, JSON_THROW_ON_ERROR),
-                'context'       => json_encode($machineEvent->context, JSON_THROW_ON_ERROR),
-                'meta'          => json_encode($machineEvent->meta, JSON_THROW_ON_ERROR),
-            ]))->toArray(),
+            values: $this->state->history->map(function (MachineEvent $machineEvent, int $index) use (&$incrementalContext, $lastHistoryEvent) {
+                // Get the context of the current machine event.
+                $changes = $machineEvent->context;
+
+                // If the current machine event is not the last one, compare its context with the incremental context and get the differences.
+                if ($machineEvent->id !== $lastHistoryEvent->id && $index > 0) {
+                    $changes = $this->arrayRecursiveDiff($changes, $incrementalContext);
+                }
+
+                // If there are changes, update the incremental context to the current event's context.
+                if (!empty($changes)) {
+                    $incrementalContext = $this->arrayRecursiveMerge($incrementalContext, $machineEvent->context);
+                }
+
+                $machineEvent->context = $changes;
+
+                return array_merge($machineEvent->toArray(), [
+                    'created_at'    => $machineEvent->created_at->toDateTimeString(),
+                    'machine_value' => json_encode($machineEvent->machine_value, JSON_THROW_ON_ERROR),
+                    'payload'       => json_encode($machineEvent->payload, JSON_THROW_ON_ERROR),
+                    'context'       => json_encode($machineEvent->context, JSON_THROW_ON_ERROR),
+                    'meta'          => json_encode($machineEvent->meta, JSON_THROW_ON_ERROR),
+                ]);
+            })->toArray(),
             uniqueBy: ['id']
         );
 
@@ -477,4 +500,48 @@ public function result(): mixed
             $arguments ?? null,
         );
     }
+
+    // region Private Methods
+    /**
+     * Compares two arrays recursively and returns the difference.
+     */
+    private function arrayRecursiveDiff(array $array1, array $array2): array
+    {
+        $difference = [];
+        foreach ($array1 as $key => $value) {
+            if (is_array($value)) {
+                if (!isset($array2[$key]) || !is_array($array2[$key])) {
+                    $difference[$key] = $value;
+                } else {
+                    $new_diff = $this->arrayRecursiveDiff($value, $array2[$key]);
+                    if (!empty($new_diff)) {
+                        $difference[$key] = $new_diff;
+                    }
+                }
+            } elseif (!array_key_exists($key, $array2) || $array2[$key] !== $value) {
+                $difference[$key] = $value;
+            }
+        }
+
+        return $difference;
+    }
+
+    /**
+     * Merges two arrays recursively.
+     */
+    protected function arrayRecursiveMerge(array $array1, array $array2): array
+    {
+        $merged = $array1;
+
+        foreach ($array2 as $key => &$value) {
+            if (is_array($value) && isset($merged[$key]) && is_array($merged[$key])) {
+                $merged[$key] = $this->arrayRecursiveMerge($merged[$key], $value);
+            } else {
+                $merged[$key] = $value;
+            }
+        }
+
+        return $merged;
+    }
+    // endregion
 }
diff --git a/tests/EventStoreTest.php b/tests/EventStoreTest.php
@@ -2,6 +2,7 @@
 
 declare(strict_types=1);
 
+use Tarfinlabs\EventMachine\Actor\Machine;
 use Tarfinlabs\EventMachine\ContextManager;
 use Tarfinlabs\EventMachine\Definition\EventDefinition;
 use Tarfinlabs\EventMachine\Definition\MachineDefinition;
@@ -159,3 +160,66 @@
             'in.transition.active.MUT.fail',
         ]);
 });
+
+it('stores incremental context', function (): void {
+    $machine = Machine::create([
+        'config' => [
+            'id'      => 'traffic_light',
+            'initial' => 'green',
+            'context' => [
+                'count' => 1,
+                'value' => 'test',
+            ],
+            'states' => [
+                'green' => [
+                    'on' => [
+                        'GREEN_TIMER' => [
+                            'target'  => 'yellow',
+                            'actions' => 'changeCount',
+                        ],
+                    ],
+                ],
+                'yellow' => [
+                    'on' => [
+                        'RED_TIMER' => [
+                            'target'  => 'red',
+                            'actions' => 'changeValue',
+                        ],
+                    ],
+                ],
+                'red' => [],
+            ],
+        ],
+        'behavior' => [
+            'actions' => [
+                'changeCount' => function (ContextManager $context): void {
+                    $context->set('count', $context->get('count') + 1);
+                },
+                'changeValue' => function (ContextManager $context): void {
+                    $context->set('value', 'retry');
+                },
+            ],
+        ],
+    ]);
+
+    $machine->send(event: [
+        'type' => 'GREEN_TIMER',
+    ]);
+
+    $newState = $machine->send(event: [
+        'type' => 'RED_TIMER',
+    ]);
+
+    expect($newState->history)
+        ->whereNotIn('type', [
+            'traffic_light.start',
+            'traffic_light.action.changeCount.finish',
+            'traffic_light.action.changeValue.finish',
+            'traffic_light.state.red.entry.finish',
+        ])->each(fn ($event) => $event->context->toEqual([]))
+        ->first()->context->toEqual(['data' => ['count' => 1, 'value' => 'test']])
+        ->where('type', 'traffic_light.action.changeCount.finish')->first()->context->toEqual(['data' => ['count' => 2]])
+        ->where('type', 'traffic_light.action.changeValue.finish')->first()->context->toEqual(['data' => ['value' => 'retry']])
+        ->last()->context->toEqual(['data' => ['count' => 2, 'value' => 'retry']]);
+
+});