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
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
// Copyright 2015 Google Inc. 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 port provides utilities for modifying and filtering
// based on the port of request URLs.
package port
import (
"encoding/json"
"net"
"net/http"
"strconv"
"strings"
"github.com/google/martian/v3"
"github.com/google/martian/v3/parse"
)
var noop = martian.Noop("port.Filter")
func init() {
parse.Register("port.Filter", filterFromJSON)
}
// Filter runs modifiers iff the port in the request URL matches port.
type Filter struct {
reqmod martian.RequestModifier
resmod martian.ResponseModifier
port int
}
type filterJSON struct {
Port int `json:"port"`
Modifier json.RawMessage `json:"modifier"`
Scope []parse.ModifierType `json:"scope"`
}
// NewFilter returns a filter that executes modifiers if the port of
// request matches port.
func NewFilter(port int) *Filter {
return &Filter{
port: port,
reqmod: noop,
resmod: noop,
}
}
// SetRequestModifier sets the request modifier.
func (f *Filter) SetRequestModifier(reqmod martian.RequestModifier) {
if reqmod == nil {
reqmod = noop
}
f.reqmod = reqmod
}
// SetResponseModifier sets the response modifier.
func (f *Filter) SetResponseModifier(resmod martian.ResponseModifier) {
if resmod == nil {
resmod = noop
}
f.resmod = resmod
}
// ModifyRequest runs the modifier if the port matches the provided port.
func (f *Filter) ModifyRequest(req *http.Request) error {
var defaultPort int
if req.URL.Scheme == "http" {
defaultPort = 80
}
if req.URL.Scheme == "https" {
defaultPort = 443
}
hasPort := strings.Contains(req.URL.Host, ":")
if hasPort {
_, p, err := net.SplitHostPort(req.URL.Host)
if err != nil {
return err
}
pt, err := strconv.Atoi(p)
if err != nil {
return err
}
if pt == f.port {
return f.reqmod.ModifyRequest(req)
}
return nil
}
// no port explictly declared - default port
if f.port == defaultPort {
return f.reqmod.ModifyRequest(req)
}
return nil
}
// ModifyResponse runs the modifier if the request URL matches urlMatcher.
func (f *Filter) ModifyResponse(res *http.Response) error {
var defaultPort int
if res.Request.URL.Scheme == "http" {
defaultPort = 80
}
if res.Request.URL.Scheme == "https" {
defaultPort = 443
}
if !strings.Contains(res.Request.URL.Host, ":") && (f.port == defaultPort) {
return f.resmod.ModifyResponse(res)
}
_, p, err := net.SplitHostPort(res.Request.URL.Host)
if err != nil {
return err
}
pt, err := strconv.Atoi(p)
if err != nil {
return err
}
if pt == f.port {
return f.resmod.ModifyResponse(res)
}
return nil
}
func filterFromJSON(b []byte) (*parse.Result, error) {
msg := &filterJSON{}
if err := json.Unmarshal(b, msg); err != nil {
return nil, err
}
filter := NewFilter(msg.Port)
r, err := parse.FromJSON(msg.Modifier)
if err != nil {
return nil, err
}
reqmod := r.RequestModifier()
if err != nil {
return nil, err
}
if reqmod != nil {
filter.SetRequestModifier(reqmod)
}
resmod := r.ResponseModifier()
if resmod != nil {
filter.SetResponseModifier(resmod)
}
return parse.NewResult(filter, msg.Scope)
}
|
