PHPLIB-814: Change stream support for point-in-time pre and post-images

Introduces fullDocumentBeforeChange option. Tests for specifying "whenAvailable" and "required" for both fullDocument and fullDocumentBeforeChange (requires MongoDB 6.0+ with changeStreamPreAndPostImages enabled on the collection).

Intentionally omits mention of FULL_DOCUMENT_DEFAULT (related to PHPLIB-808) and FULL_DOCUMENT_BEFORE_CHANGE_OFF constants, since those redundantly specified default behavior.

Tests synced with mongodb/specifications#1176

docs/includes/apiargs-MongoDBClient-method-watch-option.yaml

@@ -11,6 +11,10 @@ source:
   file: apiargs-method-watch-option.yaml
   ref: fullDocument
 ---
+source:
+  file: apiargs-method-watch-option.yaml
+  ref: fullDocumentBeforeChange
+---
 source:
   file: apiargs-method-watch-option.yaml
   ref: maxAwaitTimeMS

docs/includes/apiargs-MongoDBCollection-method-watch-option.yaml

@@ -11,6 +11,10 @@ source:
   file: apiargs-method-watch-option.yaml
   ref: fullDocument
 ---
+source:
+  file: apiargs-method-watch-option.yaml
+  ref: fullDocumentBeforeChange
+---
 source:
   file: apiargs-method-watch-option.yaml
   ref: maxAwaitTimeMS

docs/includes/apiargs-MongoDBDatabase-method-watch-option.yaml

@@ -11,6 +11,10 @@ source:
   file: apiargs-method-watch-option.yaml
   ref: fullDocument
 ---
+source:
+  file: apiargs-method-watch-option.yaml
+  ref: fullDocumentBeforeChange
+---
 source:
   file: apiargs-method-watch-option.yaml
   ref: maxAwaitTimeMS

docs/includes/apiargs-method-watch-option.yaml

@@ -13,14 +13,53 @@ arg_name: option
 name: fullDocument
 type: string
 description: |
-  Allowed values are 'default' and 'updateLookup'. Defaults to 'default'.
-  When set to 'updateLookup', the change notification for partial updates will
-  include both a delta describing the changes to the document, as well as a
-  copy of the entire document that was changed from some time after the change
-  occurred. The following values are supported:
+  Determines how the "fullDocument" response field will be populated for update
+  operations.
+
+  By default, change streams only return the delta of fields (via an
+  "udateDescription" field) for update operations and "fullDocument" is omitted.
+  Insert and replace operations always include the "fullDocument" field. Delete
+  operations omit the field as the document no longer exists.
+
+  Specify "updateLookup" to return the current majority-committed version of the
+  updated document.
+
+  MongoDB 6.0+ allows returning the post-image of the modified document if the
+  collection has ``changeStreamPreAndPostImages`` enabled. Specify
+  "whenAvailable" to return the post-image if available or a null value if not.
+  Specify "required" to return the post-image if available or raise an error if
+  not.
+
+  The following values are supported:
 
-  - ``MongoDB\Operation\Watch::FULL_DOCUMENT_DEFAULT`` (*default*)
   - ``MongoDB\Operation\Watch::FULL_DOCUMENT_UPDATE_LOOKUP``
+  - ``MongoDB\Operation\Watch::FULL_DOCUMENT_WHEN_AVAILABLE``
+  - ``MongoDB\Operation\Watch::FULL_DOCUMENT_REQUIRED``
+
+  .. note::
+
+     This is an option of the ``$changeStream`` pipeline stage.
+interface: phpmethod
+operation: ~
+optional: true
+---
+arg_name: option
+name: fullDocumentBeforeChange
+type: string
+description: |
+  Determines how the "fullDocumentBeforeChange" response field will be
+  populated. By default, the field is omitted.
+
+  MongoDB 6.0+ allows returning the pre-image of the modified document if the
+  collection has ``changeStreamPreAndPostImages`` enabled. Specify
+  "whenAvailable" to return the pre-image if available or a null value if not.
+  Specify "required" to return the pre-image if available or raise an error if
+  not.
+
+  The following values are supported:
+
+  - ``MongoDB\Operation\Watch::FULL_DOCUMENT_BEFORE_CHANGE_WHEN_AVAILABLE``
+  - ``MongoDB\Operation\Watch::FULL_DOCUMENT_BEFORE_CHANGE_REQUIRED``
 
   .. note::
 

src/Operation/Watch.php

@@ -59,6 +59,12 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
 {
     public const FULL_DOCUMENT_DEFAULT = 'default';
     public const FULL_DOCUMENT_UPDATE_LOOKUP = 'updateLookup';
+    public const FULL_DOCUMENT_WHEN_AVAILABLE = 'whenAvailable';
+    public const FULL_DOCUMENT_REQUIRED = 'required';
+
+    public const FULL_DOCUMENT_BEFORE_CHANGE_OFF = 'off';
+    public const FULL_DOCUMENT_BEFORE_CHANGE_WHEN_AVAILABLE = 'whenAvailable';
+    public const FULL_DOCUMENT_BEFORE_CHANGE_REQUIRED = 'required';
 
     /** @var integer */
     private static $wireVersionForStartAtOperationTime = 7;
@@ -105,15 +111,33 @@ class Watch implements Executable, /* @internal */ CommandSubscriber
      *
      *  * collation (document): Specifies a collation.
      *
-     *  * fullDocument (string): Determines whether the "fullDocument" field
-     *    will be populated for update operations. By default, change streams
-     *    only return the delta of fields during the update operation (via the
-     *    "updateDescription" field). To additionally return the most current
-     *    majority-committed version of the updated document, specify
-     *    "updateLookup" for this option. Defaults to "default".
+     *  * fullDocument (string): Determines how the "fullDocument" response
+     *    field will be populated for update operations.
+     *
+     *    By default, change streams only return the delta of fields (via an
+     *    "updateDescription" field) for update operations and "fullDocument" is
+     *    omitted. Insert and replace operations always include the
+     *    "fullDocument" field. Delete operations omit the field as the document
+     *    no longer exists.
+     *
+     *    Specify "updateLookup" to return the current majority-committed
+     *    version of the updated document.
+     *
+     *    MongoDB 6.0+ allows returning the post-image of the modified document
+     *    if the collection has changeStreamPreAndPostImages enabled. Specify
+     *    "whenAvailable" to return the post-image if available or a null value
+     *    if not. Specify "required" to return the post-image if available or
+     *    raise an error if not.
      *
-     *    Insert and replace operations always include the "fullDocument" field
-     *    and delete operations omit the field as the document no longer exists.
+     *  * fullDocumentBeforeChange (string): Determines how the
+     *    "fullDocumentBeforeChange" response field will be populated. By
+     *    default, the field is omitted.
+     *
+     *    MongoDB 6.0+ allows returning the pre-image of the modified document
+     *    if the collection has changeStreamPreAndPostImages enabled. Specify
+     *    "whenAvailable" to return the pre-image if available or a null value
+     *    if not. Specify "required" to return the pre-image if available or
+     *    raise an error if not.
      *
      *  * maxAwaitTimeMS (integer): The maximum amount of time for the server to
      *    wait on new documents to satisfy a change stream query.
@@ -181,6 +205,10 @@ public function __construct(Manager $manager, $databaseName, $collectionName, ar
             throw InvalidArgumentException::invalidType('"fullDocument" option', $options['fullDocument'], 'string');
         }
 
+        if (isset($options['fullDocumentBeforeChange']) && ! is_string($options['fullDocumentBeforeChange'])) {
+            throw InvalidArgumentException::invalidType('"fullDocumentBeforeChange" option', $options['fullDocumentBeforeChange'], 'string');
+        }
+
         if (! $options['readPreference'] instanceof ReadPreference) {
             throw InvalidArgumentException::invalidType('"readPreference" option', $options['readPreference'], ReadPreference::class);
         }
@@ -212,7 +240,7 @@ public function __construct(Manager $manager, $databaseName, $collectionName, ar
         }
 
         $this->aggregateOptions = array_intersect_key($options, ['batchSize' => 1, 'collation' => 1, 'maxAwaitTimeMS' => 1, 'readConcern' => 1, 'readPreference' => 1, 'session' => 1, 'typeMap' => 1]);
-        $this->changeStreamOptions = array_intersect_key($options, ['fullDocument' => 1, 'resumeAfter' => 1, 'startAfter' => 1, 'startAtOperationTime' => 1]);
+        $this->changeStreamOptions = array_intersect_key($options, ['fullDocument' => 1, 'fullDocumentBeforeChange' => 1, 'resumeAfter' => 1, 'startAfter' => 1, 'startAtOperationTime' => 1]);
 
         // Null database name implies a cluster-wide change stream
         if ($databaseName === null) {

tests/Operation/WatchTest.php

@@ -56,6 +56,10 @@ public function provideInvalidConstructorOptions()
             $options[][] = ['fullDocument' => $value];
         }
 
+        foreach ($this->getInvalidStringValues() as $value) {
+            $options[][] = ['fullDocumentBeforeChange' => $value];
+        }
+
         foreach ($this->getInvalidIntegerValues() as $value) {
             $options[][] = ['maxAwaitTimeMS' => $value];
         }

tests/UnifiedSpecTests/UnifiedSpecTest.php

@@ -21,6 +21,10 @@ class UnifiedSpecTest extends FunctionalTestCase
 {
     /** @var array */
     private static $incompleteTests = [
+        'change-streams/change-streams: to field is set in a rename change event' => 'Not yet implemented (PHPLIB-652, PHPLIB-828)',
+        'change-streams/change-streams: Test with document comment' => 'Not yet implemented (PHPLIB-749)',
+        'change-streams/change-streams: Test with string comment' => 'Not yet implemented (PHPLIB-749)',
+        'change-streams/change-streams: Test that comment is set on getMore' => 'Not yet implemented (PHPLIB-749)',
         'command-monitoring/pre-42-server-connection-id: command events do not include server connection id' => 'Not yet implemented (PHPC-1899, PHPLIB-718)',
         'command-monitoring/server-connection-id: command events include server connection id' => 'Not yet implemented (PHPC-1899, PHPLIB-718)',
         // Many load balancer tests use CMAP events and/or assertNumberConnectionsCheckedOut

tests/UnifiedSpecTests/Util.php

@@ -72,7 +72,7 @@ final class Util
         Collection::class => [
             'aggregate' => ['pipeline', 'session', 'useCursor', 'allowDiskUse', 'batchSize', 'bypassDocumentValidation', 'collation', 'comment', 'explain', 'hint', 'let', 'maxAwaitTimeMS', 'maxTimeMS'],
             'bulkWrite' => ['requests', 'session', 'ordered', 'bypassDocumentValidation'],
-            'createChangeStream' => ['pipeline', 'session', 'fullDocument', 'resumeAfter', 'startAfter', 'startAtOperationTime', 'batchSize', 'collation', 'maxAwaitTimeMS'],
+            'createChangeStream' => ['pipeline', 'session', 'fullDocument', 'fullDocumentBeforeChange', 'resumeAfter', 'startAfter', 'startAtOperationTime', 'batchSize', 'collation', 'maxAwaitTimeMS'],
             'createFindCursor' => ['filter', 'session', 'allowDiskUse', 'allowPartialResults', 'batchSize', 'collation', 'comment', 'cursorType', 'hint', 'limit', 'max', 'maxAwaitTimeMS', 'maxScan', 'maxTimeMS', 'min', 'modifiers', 'noCursorTimeout', 'oplogReplay', 'projection', 'returnKey', 'showRecordId', 'skip', 'snapshot', 'sort'],
             'createIndex' => ['keys', 'commitQuorum', 'maxTimeMS', 'name', 'session'],
             'dropIndex' => ['name', 'session', 'maxTimeMS'],