summaryrefslogtreecommitdiffstats
path: root/src/database/sql/ctxutil.go
blob: 4dbe6af6d2bee38112ebbf1061903d15998b6d1c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package sql

import (
	"context"
	"database/sql/driver"
	"errors"
)

func ctxDriverPrepare(ctx context.Context, ci driver.Conn, query string) (driver.Stmt, error) {
	if ciCtx, is := ci.(driver.ConnPrepareContext); is {
		return ciCtx.PrepareContext(ctx, query)
	}
	si, err := ci.Prepare(query)
	if err == nil {
		select {
		default:
		case <-ctx.Done():
			si.Close()
			return nil, ctx.Err()
		}
	}
	return si, err
}

func ctxDriverExec(ctx context.Context, execerCtx driver.ExecerContext, execer driver.Execer, query string, nvdargs []driver.NamedValue) (driver.Result, error) {
	if execerCtx != nil {
		return execerCtx.ExecContext(ctx, query, nvdargs)
	}
	dargs, err := namedValueToValue(nvdargs)
	if err != nil {
		return nil, err
	}

	select {
	default:
	case <-ctx.Done():
		return nil, ctx.Err()
	}
	return execer.Exec(query, dargs)
}

func ctxDriverQuery(ctx context.Context, queryerCtx driver.QueryerContext, queryer driver.Queryer, query string, nvdargs []driver.NamedValue) (driver.Rows, error) {
	if queryerCtx != nil {
		return queryerCtx.QueryContext(ctx, query, nvdargs)
	}
	dargs, err := namedValueToValue(nvdargs)
	if err != nil {
		return nil, err
	}

	select {
	default:
	case <-ctx.Done():
		return nil, ctx.Err()
	}
	return queryer.Query(query, dargs)
}

func ctxDriverStmtExec(ctx context.Context, si driver.Stmt, nvdargs []driver.NamedValue) (driver.Result, error) {
	if siCtx, is := si.(driver.StmtExecContext); is {
		return siCtx.ExecContext(ctx, nvdargs)
	}
	dargs, err := namedValueToValue(nvdargs)
	if err != nil {
		return nil, err
	}

	select {
	default:
	case <-ctx.Done():
		return nil, ctx.Err()
	}
	return si.Exec(dargs)
}

func ctxDriverStmtQuery(ctx context.Context, si driver.Stmt, nvdargs []driver.NamedValue) (driver.Rows, error) {
	if siCtx, is := si.(driver.StmtQueryContext); is {
		return siCtx.QueryContext(ctx, nvdargs)
	}
	dargs, err := namedValueToValue(nvdargs)
	if err != nil {
		return nil, err
	}

	select {
	default:
	case <-ctx.Done():
		return nil, ctx.Err()
	}
	return si.Query(dargs)
}

func ctxDriverBegin(ctx context.Context, opts *TxOptions, ci driver.Conn) (driver.Tx, error) {
	if ciCtx, is := ci.(driver.ConnBeginTx); is {
		dopts := driver.TxOptions{}
		if opts != nil {
			dopts.Isolation = driver.IsolationLevel(opts.Isolation)
			dopts.ReadOnly = opts.ReadOnly
		}
		return ciCtx.BeginTx(ctx, dopts)
	}

	if opts != nil {
		// Check the transaction level. If the transaction level is non-default
		// then return an error here as the BeginTx driver value is not supported.
		if opts.Isolation != LevelDefault {
			return nil, errors.New("sql: driver does not support non-default isolation level")
		}

		// If a read-only transaction is requested return an error as the
		// BeginTx driver value is not supported.
		if opts.ReadOnly {
			return nil, errors.New("sql: driver does not support read-only transactions")
		}
	}

	if ctx.Done() == nil {
		return ci.Begin()
	}

	txi, err := ci.Begin()
	if err == nil {
		select {
		default:
		case <-ctx.Done():
			txi.Rollback()
			return nil, ctx.Err()
		}
	}
	return txi, err
}

func namedValueToValue(named []driver.NamedValue) ([]driver.Value, error) {
	dargs := make([]driver.Value, len(named))
	for n, param := range named {
		if len(param.Name) > 0 {
			return nil, errors.New("sql: driver does not support the use of Named Parameters")
		}
		dargs[n] = param.Value
	}
	return dargs, nil
}