forked from casbin/casbin
-
Notifications
You must be signed in to change notification settings - Fork 0
/
adapter_filtered.go
138 lines (121 loc) · 3.39 KB
/
adapter_filtered.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
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
// Copyright 2017 The casbin Authors. All Rights Reserved.
//
// 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 fileadapter
import (
"bufio"
"errors"
"os"
"strings"
"github.com/casbin/casbin/v2/model"
"github.com/casbin/casbin/v2/persist"
)
// FilteredAdapter is the filtered file adapter for Casbin. It can load policy
// from file or save policy to file and supports loading of filtered policies.
type FilteredAdapter struct {
*Adapter
filtered bool
}
// Filter defines the filtering rules for a FilteredAdapter's policy. Empty values
// are ignored, but all others must match the filter.
type Filter struct {
P []string
G []string
}
// NewFilteredAdapter is the constructor for FilteredAdapter.
func NewFilteredAdapter(filePath string) *FilteredAdapter {
a := FilteredAdapter{}
a.filtered = true
a.Adapter = NewAdapter(filePath)
return &a
}
// LoadPolicy loads all policy rules from the storage.
func (a *FilteredAdapter) LoadPolicy(model model.Model) error {
a.filtered = false
return a.Adapter.LoadPolicy(model)
}
// LoadFilteredPolicy loads only policy rules that match the filter.
func (a *FilteredAdapter) LoadFilteredPolicy(model model.Model, filter interface{}) error {
if filter == nil {
return a.LoadPolicy(model)
}
if a.filePath == "" {
return errors.New("invalid file path, file path cannot be empty")
}
filterValue, ok := filter.(*Filter)
if !ok {
return errors.New("invalid filter type")
}
err := a.loadFilteredPolicyFile(model, filterValue, persist.LoadPolicyLine)
if err == nil {
a.filtered = true
}
return err
}
func (a *FilteredAdapter) loadFilteredPolicyFile(model model.Model, filter *Filter, handler func(string, model.Model)) error {
f, err := os.Open(a.filePath)
if err != nil {
return err
}
defer f.Close()
scanner := bufio.NewScanner(f)
for scanner.Scan() {
line := strings.TrimSpace(scanner.Text())
if filterLine(line, filter) {
continue
}
handler(line, model)
}
return scanner.Err()
}
// IsFiltered returns true if the loaded policy has been filtered.
func (a *FilteredAdapter) IsFiltered() bool {
return a.filtered
}
// SavePolicy saves all policy rules to the storage.
func (a *FilteredAdapter) SavePolicy(model model.Model) error {
if a.filtered {
return errors.New("cannot save a filtered policy")
}
return a.Adapter.SavePolicy(model)
}
func filterLine(line string, filter *Filter) bool {
if filter == nil {
return false
}
p := strings.Split(line, ",")
if len(p) == 0 {
return true
}
var filterSlice []string
switch strings.TrimSpace(p[0]) {
case "p":
filterSlice = filter.P
case "g":
filterSlice = filter.G
}
return filterWords(p, filterSlice)
}
func filterWords(line []string, filter []string) bool {
if len(line) < len(filter)+1 {
return true
}
var skipLine bool
for i, v := range filter {
if len(v) > 0 && strings.TrimSpace(v) != strings.TrimSpace(line[i+1]) {
skipLine = true
break
}
}
return skipLine
}