feat: expose new read_time API fields, currently only available in private preview (#932)

PiperOrigin-RevId: 440914241
Source-Link: googleapis/googleapis@0ed730f
Source-Link: googleapis/googleapis-gen@b2e5ae9
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See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md
Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: gcf-owl-bot[bot]

protos/google/datastore/v1/datastore.proto

@@ -21,6 +21,7 @@ import "google/api/client.proto";
 import "google/api/field_behavior.proto";
 import "google/datastore/v1/entity.proto";
 import "google/datastore/v1/query.proto";
+import "google/protobuf/timestamp.proto";
 
 option csharp_namespace = "Google.Cloud.Datastore.V1";
 option go_package = "google.golang.org/genproto/googleapis/datastore/v1;datastore";
@@ -138,6 +139,9 @@ message LookupResponse {
   // order of results in this field is undefined and has no relation to the
   // order of the keys in the input.
   repeated Key deferred = 3;
+
+  // The time at which these entities were read or found missing.
+  google.protobuf.Timestamp read_time = 7;
 }
 
 // The request for [Datastore.RunQuery][google.datastore.v1.Datastore.RunQuery].
@@ -259,6 +263,9 @@ message CommitResponse {
   // The number of index entries updated during the commit, or zero if none were
   // updated.
   int32 index_updates = 4;
+
+  // The transaction commit timestamp. Not set for non-transactional commits.
+  google.protobuf.Timestamp commit_time = 8;
 }
 
 // The request for [Datastore.AllocateIds][google.datastore.v1.Datastore.AllocateIds].
@@ -332,6 +339,11 @@ message Mutation {
     // to. If this does not match the current version on the server, the
     // mutation conflicts.
     int64 base_version = 8;
+
+    // The update time of the entity that this mutation is being applied
+    // to. If this does not match the current update time on the server, the
+    // mutation conflicts.
+    google.protobuf.Timestamp update_time = 11;
   }
 }
 
@@ -348,6 +360,12 @@ message MutationResult {
   // than the version of any possible future entity.
   int64 version = 4;
 
+  // The update time of the entity on the server after processing the mutation.
+  // If the mutation doesn't change anything on the server, then the timestamp
+  // will be the update timestamp of the current entity. This field will not be
+  // set after a 'delete'.
+  google.protobuf.Timestamp update_time = 6;
+
   // Whether a conflict was detected for this mutation. Always false when a
   // conflict detection strategy field is not set in the mutation.
   bool conflict_detected = 5;
@@ -386,6 +404,11 @@ message ReadOptions {
     // transaction identifier is returned by a call to
     // [Datastore.BeginTransaction][google.datastore.v1.Datastore.BeginTransaction].
     bytes transaction = 2;
+
+    // Reads entities as they were at the given time. This may not be older
+    // than 270 seconds.  This value is only supported for Cloud Firestore in
+    // Datastore mode.
+    google.protobuf.Timestamp read_time = 4;
   }
 }
 
@@ -403,7 +426,9 @@ message TransactionOptions {
 
   // Options specific to read-only transactions.
   message ReadOnly {
-
+    // Reads entities at the given time.
+    // This may not be older than 60 seconds.
+    google.protobuf.Timestamp read_time = 1;
   }
 
   // The `mode` of the transaction, indicating whether write operations are

protos/google/datastore/v1/query.proto

@@ -17,6 +17,7 @@ syntax = "proto3";
 package google.datastore.v1;
 
 import "google/datastore/v1/entity.proto";
+import "google/protobuf/timestamp.proto";
 import "google/protobuf/wrappers.proto";
 
 option csharp_namespace = "Google.Cloud.Datastore.V1";
@@ -62,6 +63,12 @@ message EntityResult {
   // is always set except for eventually consistent reads.
   int64 version = 4;
 
+  // The time at which the entity was last changed.
+  // This field is set for [`FULL`][google.datastore.v1.EntityResult.ResultType.FULL] entity
+  // results.
+  // If this entity is missing, this field will not be set.
+  google.protobuf.Timestamp update_time = 5;
+
   // A cursor that points to the position after the result entity.
   // Set only when the `EntityResult` is part of a `QueryResultBatch` message.
   bytes cursor = 3;
@@ -353,4 +360,16 @@ message QueryResultBatch {
   // is valid for all preceding batches.
   // The value will be zero for eventually consistent queries.
   int64 snapshot_version = 7;
+
+  // Read timestamp this batch was returned from.
+  // This applies to the range of results from the query's `start_cursor` (or
+  // the beginning of the query if no cursor was given) to this batch's
+  // `end_cursor` (not the query's `end_cursor`).
+  //
+  // In a single transaction, subsequent query result batches for the same query
+  // can have a greater timestamp. Each batch's read timestamp
+  // is valid for all preceding batches.
+  // This value will not be set for eventually consistent queries in Cloud
+  // Datastore.
+  google.protobuf.Timestamp read_time = 8;
 }