summaryrefslogtreecommitdiffstats
path: root/vendor/github.com/go-redis/redis/pipeline.go
blob: b66c0597f575254e210564f7ea890fc3dca1afbb (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
package redis

import (
	"sync"

	"github.com/go-redis/redis/internal/pool"
)

type pipelineExecer func([]Cmder) error

type Pipeliner interface {
	StatefulCmdable
	Process(cmd Cmder) error
	Close() error
	Discard() error
	discard() error
	Exec() ([]Cmder, error)
	pipelined(fn func(Pipeliner) error) ([]Cmder, error)
}

var _ Pipeliner = (*Pipeline)(nil)

// Pipeline implements pipelining as described in
// http://redis.io/topics/pipelining. It's safe for concurrent use
// by multiple goroutines.
type Pipeline struct {
	statefulCmdable

	exec pipelineExecer

	mu     sync.Mutex
	cmds   []Cmder
	closed bool
}

func (c *Pipeline) Process(cmd Cmder) error {
	c.mu.Lock()
	c.cmds = append(c.cmds, cmd)
	c.mu.Unlock()
	return nil
}

// Close closes the pipeline, releasing any open resources.
func (c *Pipeline) Close() error {
	c.mu.Lock()
	c.discard()
	c.closed = true
	c.mu.Unlock()
	return nil
}

// Discard resets the pipeline and discards queued commands.
func (c *Pipeline) Discard() error {
	c.mu.Lock()
	err := c.discard()
	c.mu.Unlock()
	return err
}

func (c *Pipeline) discard() error {
	if c.closed {
		return pool.ErrClosed
	}
	c.cmds = c.cmds[:0]
	return nil
}

// Exec executes all previously queued commands using one
// client-server roundtrip.
//
// Exec always returns list of commands and error of the first failed
// command if any.
func (c *Pipeline) Exec() ([]Cmder, error) {
	c.mu.Lock()
	defer c.mu.Unlock()

	if c.closed {
		return nil, pool.ErrClosed
	}

	if len(c.cmds) == 0 {
		return nil, nil
	}

	cmds := c.cmds
	c.cmds = nil

	return cmds, c.exec(cmds)
}

func (c *Pipeline) pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
	if err := fn(c); err != nil {
		return nil, err
	}
	cmds, err := c.Exec()
	_ = c.Close()
	return cmds, err
}

func (c *Pipeline) Pipelined(fn func(Pipeliner) error) ([]Cmder, error) {
	return c.pipelined(fn)
}

func (c *Pipeline) Pipeline() Pipeliner {
	return c
}