-
Notifications
You must be signed in to change notification settings - Fork 67
/
numerical.go
79 lines (65 loc) · 1.92 KB
/
numerical.go
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
/*
Copyright 2021 The Flux authors
Licensed 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 policy
import (
"fmt"
"strconv"
)
const (
// NumericalOrderAsc ascending order
NumericalOrderAsc = "ASC"
// NumericalOrderDesc descending order
NumericalOrderDesc = "DESC"
)
// Numerical representes a Numerical ordering policy
type Numerical struct {
Order string
}
// NewNumerical constructs a Numerical object validating the provided
// order argument
func NewNumerical(order string) (*Numerical, error) {
switch order {
case "":
order = NumericalOrderAsc
case NumericalOrderAsc, NumericalOrderDesc:
break
default:
return nil, fmt.Errorf("invalid order argument provided: '%s', must be one of: %s, %s", order, NumericalOrderAsc, NumericalOrderDesc)
}
return &Numerical{
Order: order,
}, nil
}
// Latest returns latest version from a provided list of strings
func (p *Numerical) Latest(versions []string) (string, error) {
if len(versions) == 0 {
return "", fmt.Errorf("version list argument cannot be empty")
}
var latest string
var pv float64
for i, version := range versions {
cv, err := strconv.ParseFloat(version, 64)
if err != nil {
return "", fmt.Errorf("failed to parse invalid numeric value '%s'", version)
}
switch {
case i == 0:
// First iteration, nothing to compare
case p.Order == NumericalOrderAsc && cv < pv, p.Order == NumericalOrderDesc && cv > pv:
continue
}
latest = version
pv = cv
}
return latest, nil
}