scan_struct_test.go

// Licensed to ClickHouse, Inc. under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. ClickHouse, Inc. licenses this file to you under
// the Apache License, Version 2.0 (the "License"); you may
// not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package tests

import (
	"context"
	"fmt"
	"github.com/stretchr/testify/require"
	"testing"
	"time"

	"github.com/IevgenLuzan/clickhouse-go/v2"
	"github.com/stretchr/testify/assert"
)

func TestQueryRowScanStruct(t *testing.T) {
	conn, err := GetNativeConnection(nil, nil, &clickhouse.Compression{
		Method: clickhouse.CompressionLZ4,
	})
	ctx := context.Background()
	require.NoError(t, err)
	var result struct {
		Col1 string `ch:"col1"`
		Col2 uint8  `ch:"col2"`
		Col3 *uint8 `ch:"col3"`
		Col4 *uint8 `ch:"col4"`
	}
	require.NoError(t, conn.QueryRow(ctx, "SELECT 'ABC' AS col1, 42 AS col2, 5 AS col3, NULL AS col4").ScanStruct(&result))
	require.Nil(t, result.Col4)
	assert.Equal(t, "ABC", result.Col1)
	assert.Equal(t, uint8(42), result.Col2)
	assert.Equal(t, uint8(5), *result.Col3)
}
func TestQueryScanStruct(t *testing.T) {
	conn, err := GetNativeConnection(nil, nil, &clickhouse.Compression{
		Method: clickhouse.CompressionLZ4,
	})
	ctx := context.Background()
	require.NoError(t, err)
	rows, err := conn.Query(ctx, "SELECT number, 'ABC_' || CAST(number AS String) AS col1, now() AS time FROM system.numbers LIMIT 5")
	require.NoError(t, err)
	var i uint64
	for rows.Next() {
		var result struct {
			Col1 uint64    `ch:"number"`
			Col2 string    `ch:"col1"`
			Col3 time.Time `ch:"time"`
		}
		if assert.NoError(t, rows.ScanStruct(&result)) {
			assert.Equal(t, i, result.Col1)
			assert.Equal(t, fmt.Sprintf("ABC_%d", i), result.Col2)
		}
		i++
	}
	require.NoError(t, rows.Close())
	assert.NoError(t, rows.Err())
}

func TestSelectScanStruct(t *testing.T) {
	conn, err := GetNativeConnection(nil, nil, &clickhouse.Compression{
		Method: clickhouse.CompressionLZ4,
	})
	ctx := context.Background()
	require.NoError(t, err)
	var result []struct {
		Col1 uint64     `ch:"number"`
		Col2 string     `ch:"col1"`
		Col3 *time.Time `ch:"time"`
	}
	require.NoError(t, conn.Select(ctx, &result, "SELECT number, 'ABC_' || CAST(number AS String) AS col1, now() AS time FROM system.numbers LIMIT 5"))
	require.Len(t, result, 5)
	for i, v := range result {
		if assert.NotNil(t, v.Col3) {
			assert.Equal(t, uint64(i), v.Col1)
			assert.Equal(t, fmt.Sprintf("ABC_%d", i), v.Col2)
		}
	}
}