spannertest: error getting data with json

[jfajardo]

Issue Description:

When executing a SELECT query in Spanner using Go, I encounter the following error:

spanner: code = "Unknown", desc = "rpc error: code = Unknown desc = unhandled base type 8"

Context:
I am working with a table that contains a JSON type column. The error occurs when trying to read data from that column during a SELECT query.

Steps to Reproduce:

• Create a table with a JSON type column.
• Insert data into the JSON column.
• Execute a SELECT query to retrieve data from that column.
• The error is encountered when reading the JSON field.

Relevant Code:

package spanner

import (
	"context"
	"fmt"
	"testing"

	"cloud.google.com/go/spanner"
	database "cloud.google.com/go/spanner/admin/database/apiv1"
	"cloud.google.com/go/spanner/admin/database/apiv1/databasepb"
	"cloud.google.com/go/spanner/spannertest"
	"github.com/stretchr/testify/assert"
	"google.golang.org/api/option"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

func setupTableTest(t *testing.T) (context.Context, *spanner.Client, func()) {
	ctx := context.Background()
	server, err := spannertest.NewServer(":0")
	assert.NoError(t, err)

	conn, err := grpc.NewClient(server.Addr, grpc.WithTransportCredentials(insecure.NewCredentials()))
	assert.NoError(t, err)

	dbClient, err := database.NewDatabaseAdminClient(ctx, option.WithGRPCConn(conn))
	assert.NoError(t, err)

	op, err := dbClient.UpdateDatabaseDdl(ctx, &databasepb.UpdateDatabaseDdlRequest{
		Database: "test-db",
		Statements: []string{
			`CREATE TABLE test_table (
				id STRING(30) NOT NULL,
				other_id STRING(30) NOT NULL,
				data JSON
			) PRIMARY KEY (id, other_id)`,
		},
	})
	assert.NoError(t, err)
	assert.NoError(t, op.Wait(ctx))

	spannerClient, err := spanner.NewClient(ctx, "projects/my-project/instances/my-instance/databases/test-db", option.WithGRPCConn(conn))
	assert.NoError(t, err)

	return ctx, spannerClient, func() {
		spannerClient.Close()
		server.Close()
	}
}

func checkInsertedData(client *spanner.Client, ctx context.Context) error {
	query := `SELECT id, other_id, data FROM test_table`

	stmt := spanner.Statement{
		SQL: query,
	}

	iter := client.Single().Query(ctx, stmt)
	defer iter.Stop()

	for {
		row, err := iter.Next()
		fmt.Println(err)
		fmt.Println(row)
	}
}

func TestTableStorage(t *testing.T) {
	ctx, client, teardown := setupTableTest(t)
	defer teardown()

	cb := func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
		data := `[{"a": "a"}, {"b": "b"}]`
		stmt := spanner.Statement{
			SQL: `INSERT INTO test_table (id, other_id, data) VALUES (@id, @other_id, @data)`,
			Params: map[string]interface{}{
				"id":       "1",
				"other_id": "111",
				"data":     data,
			},
		}
		_, err := txn.Update(ctx, stmt)
		if err != nil {
			return fmt.Errorf("failed to perform insert, err: %w", err)
		}
		return nil
	}
	r, err := client.ReadWriteTransaction(ctx, cb)
	fmt.Println(r)
	fmt.Println(err)

	checkInsertedData(client, ctx)

}

Expected Behavior:
The SELECT query should return the stored JSON data from the recommendations column without errors.

Actual Behavior:
The error rpc error: code = Unknown desc = unhandled base type 8 occurs when trying to read the recommendations column of type JSON.

Environment:
Go version: go1.21.4
Spanner client version: cloud.google.com/go/spanner v1.23.0
Spanner Emulator: spannertest
This focuses specifically on the issue occurring during the SELECT query on the JSON column.