spanner: add support for struct in client executor - extractRowArrayValue

[harshachinta]

The extractRowArrayValue in executor converts a single column's array value at given index i to executor value.
However, the current methid lacks conversion when the type is TYPECODE_STRUCT.

google-cloud-go/spanner/test/cloudexecutor/executor/internal/utility/spanner_to_executor_value_converter.go

Line 163 in f087721

func extractRowArrayValue(row *spanner.Row, i int, t *sppb.Type) (*executorpb.Value, error) {

b/382335717
The systests failed with the below error

ABORTED: RandomBatchTransactions (workid: Writes-auto-1733354544808703-184) failed: ABORTED: INVALID_ARGUMENT: Execution failed for batch partition, Failed action: database_path: 	 "projects/spanner-cloud-systest/instances/cloud-systest0/databases/read_write_test" execute_partition { partition { cloud { cloud_partition: "\376\026\235\n\000\376\026\230AAeMGCkgu1tMiWfkcmWr9vrj__ReDkWrgi_78TXrybZ2wxPpd-BoeThAJWw-QdactF0bWA8IS4aUqaLq3yq4cF_w-acMGAH5-3GXBlDkQ9ath3NFGeRtZj28x1dBb96I3azzxYYp1z33WfzihkF_4WaYFW2VX58LQymm2953Huz3N_cuFH9m7KVCd2LH1YuBeBojhaJqn-rL9Nkb06IAtaJXe3HEbkW8tvIjXJbw3KVPvyvljSA5Eilizt7q_HUH-wjdPNyUqgVC3YSOEHyjpGMqGKm5ZUE5BDR6E94YDS1haLhhPE_ZB0eM4oelQ46fwhJ...[Action Truncated]:  spanner: code = "InvalidArgument", desc = "extractRowArrayValue: unable to extract value: type STRUCT not supported"
Transaction Writes-auto-1733354544808703-184/137534 @1733355445173947 (2024/12/04-15:37:25.173947-08:00)  schema_generation=3  dma_ctx=no concurrency=batch=1733355445173947:
  Read log scopes: [Folders(5,0q*)..Folders(5,0q*)]
Query: 
SET sql_version 1;
BIND p0 false;
BIND p1 NUMERIC "-24418225444244624169241243163.783041211";
SELECT
  projectscan_6.a_2 AS expr0_7,
  COALESCE(ARRAY< STRUCT< int64_f INT64 > >[], projectscan_6.a_5) AS expr1_10
FROM
  (
    SELECT
      (CAST(@p1 AS STRING) IN (
        SELECT
          SAFE_CAST(JSON_VALUE('{"array":[null,3.974676704235172e+307],"bool":true,"null":null,"number_float":1.1206932170878527e+307,"number_integer":-7917485124678447281,"number_unsigned":16839281082195424947,"object":{"array":[-9006197925947932233],"string":"RQ3eN2PEG:RxD6NSD6XXghNyUNbhK5rQAnS"},"string":"l3HUGxIykZQGt7snzfsGVg2DQPDO7i4nssqwp4nNQGojS0GTVg"}',
            "$.object.string") AS STRING) AS a_4
        FROM
          (
            SELECT
              1
          ) AS singlerowscan_3
        WHERE
          @p0
      )) AS a_2,
      ARRAY< STRUCT< int64_f INT64 > >[STRUCT< int64_f INT64 > (-6524593091844119782), STRUCT< int64_f INT64 >
      (-101546339316740543), STRUCT< int64_f INT64 > (1496238184691556105), STRUCT< int64_f INT64 > (-3132155766874334742)] AS a_5
    FROM
      (
        SELECT
          1
      ) AS singlerowscan_1
    WHERE
      true
  ) AS projectscan_6;
To debug this, you may want to replay the batch transaction with the following command, adding a watch table and keys for the rows that differ:
RUN: spanner/automatic_build/systest/fetch_and_run_driver.sh systest_1204_14_702859027 read_write --systest_id=cloudclientquickgo-ra-1204-14 --spanner_systest_label=cloudclientquickgo --spanner_systest_cell=ra --systest_port=0 --client_mdb_group=spanner-test --systest_extra_command_arg=--spanner_test_profile=systest:group=system,binary=read_write_worker,script=read_write,label=cloudclientquickgo --systest_extra_command_arg=--spandex_enable_systestable_query_features --systest_extra_command_arg=--spanner_systest_prob_partition_hint=0.8 --cloud  replaybatchtransaction projects/spanner-cloud-systest/instances/cloud-systest0/databases/read_write_test readonly 1733355445173947 3 Writes-auto-1733354544808703-184 137534 [<watch table> <watch keys>]
=== Source Location Trace: ===
spanner/systest/handlers/read_write.cc:3152
 [type.googleapis.com/util.ErrorSpacePayload='storage_systest::SYSTEST_FAILED']