forked from rancher/wrangler
/
router.go
155 lines (127 loc) · 3.62 KB
/
router.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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
package webhook
import (
"context"
"encoding/json"
"fmt"
"net/http"
jsonpatch "github.com/evanphx/json-patch"
"github.com/sirupsen/logrus"
v1 "k8s.io/api/admission/v1"
"k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
"k8s.io/apimachinery/pkg/runtime"
)
var (
defObjType = &unstructured.Unstructured{}
jsonPatchType = v1.PatchTypeJSONPatch
)
func NewRouter() *Router {
return &Router{}
}
type Router struct {
matches []*RouteMatch
}
func (r *Router) sendError(rw http.ResponseWriter, review *v1.AdmissionReview, err error) {
logrus.Debug(err)
if review == nil || review.Request == nil {
http.Error(rw, err.Error(), http.StatusInternalServerError)
return
}
review.Response.Result = &errors.NewInternalError(err).ErrStatus
writeResponse(rw, review)
}
func writeResponse(rw http.ResponseWriter, review *v1.AdmissionReview) {
rw.Header().Set("Content-Type", "application/json")
json.NewEncoder(rw).Encode(review)
}
func (r *Router) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
review := &v1.AdmissionReview{}
err := json.NewDecoder(req.Body).Decode(review)
if err != nil {
r.sendError(rw, review, err)
return
}
if review.Request == nil {
r.sendError(rw, review, fmt.Errorf("request is not set"))
return
}
response := &Response{
AdmissionResponse: v1.AdmissionResponse{
UID: review.Request.UID,
},
}
review.Response = &response.AdmissionResponse
if err := r.admit(response, review.Request, req); err != nil {
r.sendError(rw, review, err)
return
}
writeResponse(rw, review)
}
func (r *Router) admit(response *Response, request *v1.AdmissionRequest, req *http.Request) error {
for _, m := range r.matches {
if m.matches(request) {
err := m.admit(response, &Request{
AdmissionRequest: *request,
Context: req.Context(),
objTemplate: m.getObjType(),
})
logrus.Debugf("admit result: %s %s %s user=%s allowed=%v err=%v", request.Operation, request.Kind.String(), resourceString(request.Namespace, request.Name), request.UserInfo.Username, response.Allowed, err)
return err
}
}
logrus.Debugf("no route match found for %s %s %s", request.Operation, request.Kind.String(), resourceString(request.Namespace, request.Name))
return nil
}
func (r *Router) next() *RouteMatch {
match := &RouteMatch{}
r.matches = append(r.matches, match)
return match
}
type Request struct {
v1.AdmissionRequest
Context context.Context
objTemplate runtime.Object
}
func (r *Request) DecodeOldObject() (runtime.Object, error) {
obj := r.objTemplate.DeepCopyObject()
err := json.Unmarshal(r.OldObject.Raw, obj)
return obj, err
}
func (r *Request) DecodeObject() (runtime.Object, error) {
obj := r.objTemplate.DeepCopyObject()
err := json.Unmarshal(r.Object.Raw, obj)
return obj, err
}
type Response struct {
v1.AdmissionResponse
}
func (r *Response) CreatePatch(request *Request, newObj runtime.Object) error {
if len(r.Patch) > 0 {
return fmt.Errorf("response patch has already been already been assigned")
}
newBytes, err := json.Marshal(newObj)
if err != nil {
return err
}
patch, err := jsonpatch.CreateMergePatch(request.Object.Raw, newBytes)
if err != nil {
return err
}
r.Patch = patch
r.PatchType = &jsonPatchType
return nil
}
type Handler interface {
Admit(resp *Response, req *Request) error
}
type HandlerFunc func(resp *Response, req *Request) error
func (h HandlerFunc) Admit(resp *Response, req *Request) error {
return h(resp, req)
}
// resourceString returns the resource formatted as a string
func resourceString(ns, name string) string {
if ns == "" {
return name
}
return fmt.Sprintf("%s/%s", ns, name)
}