ducky/devices
2015-12-19
Parent:a700ede02f91
ducky/devices/vendor/code.secondbit.org/api.hg/api.go
Fix JSON pointers in errors when creating devices. Our JSON pointers used to point at the root of the document, but the properties were actually in objects in an array keyed off of "devices", so we had to update the field property of our errors to match. While we were in there, we fixed the "insufficient" error for a Device's name to be "missing" when the name is an empty string. So far, the only way for a Device's name for it to be insufficient is _for it to be the empty string_, but if in the future we raise the minimum length of the Device name, there will be a distinction and I'd like the code to recognise it.
1 package api
3 import (
4 "encoding/json"
5 "errors"
6 "log"
7 "net/http"
8 "sort"
9 "strings"
11 "bitbucket.org/ww/goautoneg"
13 "code.secondbit.org/uuid.hg"
15 "golang.org/x/net/context"
16 )
18 const (
19 RequestErrAccessDenied = "access_denied"
20 RequestErrInsufficient = "insufficient"
21 RequestErrOverflow = "overflow"
22 RequestErrInvalidValue = "invalid_value"
23 RequestErrInvalidFormat = "invalid_format"
24 RequestErrMissing = "missing"
25 RequestErrNotFound = "not_found"
26 RequestErrConflict = "conflict"
27 RequestErrActOfGod = "act_of_god"
28 )
30 var (
31 ActOfGodError = []RequestError{{Slug: RequestErrActOfGod}}
32 InvalidFormatError = []RequestError{{Slug: RequestErrInvalidFormat, Field: "/"}}
33 AccessDeniedError = []RequestError{{Slug: RequestErrAccessDenied}}
35 Encoders = []string{"application/json"}
37 ErrUserIDNotSet = errors.New("user ID not set")
38 )
40 type RequestError struct {
41 Slug string `json:"error,omitempty"`
42 Field string `json:"field,omitempty"`
43 Param string `json:"param,omitempty"`
44 Header string `json:"header,omitempty"`
45 }
47 type ContextHandler func(context.Context, http.ResponseWriter, *http.Request)
49 func NegotiateMiddleware(h http.Handler) http.Handler {
50 return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
51 if r.Header.Get("Accept") != "" {
52 contentType := goautoneg.Negotiate(r.Header.Get("Accept"), Encoders)
53 if contentType == "" {
54 w.WriteHeader(http.StatusNotAcceptable)
55 w.Write([]byte("Unsupported content type requested: " + r.Header.Get("Accept")))
56 return
57 }
58 }
59 h.ServeHTTP(w, r)
60 })
61 }
63 func Encode(w http.ResponseWriter, r *http.Request, status int, resp interface{}) {
64 contentType := goautoneg.Negotiate(r.Header.Get("Accept"), Encoders)
65 w.Header().Set("content-type", contentType)
66 w.WriteHeader(status)
67 var err error
68 switch contentType {
69 case "application/json":
70 enc := json.NewEncoder(w)
71 err = enc.Encode(resp)
72 default:
73 enc := json.NewEncoder(w)
74 err = enc.Encode(resp)
75 }
76 if err != nil {
77 log.Println(err)
78 }
79 }
81 func Decode(r *http.Request, target interface{}) error {
82 defer r.Body.Close()
83 switch r.Header.Get("Content-Type") {
84 case "application/json":
85 dec := json.NewDecoder(r.Body)
86 return dec.Decode(target)
87 default:
88 dec := json.NewDecoder(r.Body)
89 return dec.Decode(target)
90 }
91 }
93 func CORSMiddleware(h http.Handler) http.Handler {
94 return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
95 w.Header().Set("Access-Control-Allow-Origin", "*")
96 w.Header().Set("Access-Control-Allow-Headers", r.Header.Get("Access-Control-Request-Headers"))
97 w.Header().Set("Access-Control-Allow-Credentials", "true")
98 if strings.ToLower(r.Method) == "options" {
99 methods := strings.Join(r.Header[http.CanonicalHeaderKey("Trout-Methods")], ", ")
100 w.Header().Set("Access-Control-Allow-Methods", methods)
101 w.Header().Set("Allow", methods)
102 w.WriteHeader(http.StatusOK)
103 return
104 }
105 h.ServeHTTP(w, r)
106 })
107 }
109 func ContextWrapper(c context.Context, handler ContextHandler) http.Handler {
110 return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
111 handler(c, w, r)
112 })
113 }
115 func CheckScopes(scopes []string, checking ...string) bool {
116 sort.Strings(scopes)
117 for _, scope := range checking {
118 found := sort.SearchStrings(scopes, scope)
119 if found == len(scopes) || scopes[found] != scope {
120 return false
121 }
122 }
123 return true
124 }
126 func GetScopes(r *http.Request) []string {
127 scopes := strings.Split(r.Header.Get("scopes"), " ")
128 for pos, scope := range scopes {
129 scopes[pos] = strings.TrimSpace(scope)
130 }
131 sort.Strings(scopes)
132 return scopes
133 }
135 func AuthUser(r *http.Request) (uuid.ID, error) {
136 rawID := r.Header.Get("User-ID")
137 if rawID == "" {
138 return nil, ErrUserIDNotSet
139 }
140 return uuid.Parse(rawID)
141 }