DOCSP-31215 - startup mode (#170)

(cherry picked from commit 086edd3)

Author: mongoKart

source/configuration/read.txt

@@ -289,9 +289,6 @@ You must specify this partitioner using the full classname:
 
 This partitioner creates a single partition.
 
-
-
-
 .. _spark-change-stream-conf:
 
 Change Streams
@@ -329,6 +326,20 @@ Change Streams
           see the MongoDB server manual guide
           :manual:`Lookup Full Document for Update Operation </changeStreams/#lookup-full-document-for-update-operations>`.
 
+   * - ``change.stream.micro.batch.max.partition.count``
+     - | The maximum number of partitions the {+connector-short+} divides each 
+         micro-batch into. Spark workers can process these partitions in parallel.
+       |  
+       | This setting applies only when using micro-batch streams.
+       |
+       | **Default**: ``1``
+
+       .. warning:: Event Order
+
+          Specifying a value larger than ``1`` can alter the order in which
+          the {+connector-short+} processes change events. Avoid this setting
+          if out-of-order processing could create data inconsistencies downstream. 
+
    * - ``change.stream.publish.full.document.only``
      - | Specifies whether to publish the changed document or the full
          change stream document.
@@ -348,20 +359,29 @@ Change Streams
           This setting overrides the ``change.stream.lookup.full.document``
           setting.
 
-   * - ``change.stream.micro.batch.max.partition.count``
-     - | The maximum number of partitions the {+connector-short+} divides each 
-         micro-batch into. Spark workers can process these partitions in parallel.
-       |  
-       | This setting applies only when using micro-batch streams.
-       |
-       | **Default**: ``1``
-
-       .. warning:: Event Order
-
-          Specifying a value larger than ``1`` can alter the order in which
-          the {+connector-short+} processes change events. Avoid this setting
-          if out-of-order processing could create data inconsistencies downstream. 
-
+   * - ``change.stream.startup.mode``
+     - | Specifies how the connector starts up when no offset is available.
+       
+       | This setting accepts the following values:
+        
+       - ``latest``: The connector begins processing
+         change events starting with the most recent event.
+         It will not process any earlier unprocessed events.
+       - ``timestamp``: The connector begins processing change events at a specified time.
+           
+         To use the ``timestamp`` option, you must specify a time by using the
+         ``change.stream.startup.mode.timestamp.start.at.operation.time`` setting.
+         This setting accepts timestamps in the following formats:
+         
+         - An integer representing the number of seconds since the
+           :wikipedia:`Unix epoch <Unix_time>`
+         - A date and time in
+           `ISO-8601 <https://www.iso.org/iso-8601-date-and-time-format.html>`__
+           format with one-second precision
+         - An extended JSON ``BsonTimestamp``
+       
+         **Default**: ``latest``
+       
 .. _configure-input-uri:
 
 ``connection.uri`` Configuration Setting