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
|
package httputils
import (
"net/http"
"strings"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/versions"
"github.com/gorilla/mux"
"github.com/sirupsen/logrus"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
)
// httpStatusError is an interface
// that errors with custom status codes
// implement to tell the api layer
// which response status to set.
type httpStatusError interface {
HTTPErrorStatusCode() int
}
// inputValidationError is an interface
// that errors generated by invalid
// inputs can implement to tell the
// api layer to set a 400 status code
// in the response.
type inputValidationError interface {
IsValidationError() bool
}
// GetHTTPErrorStatusCode retrieves status code from error message.
func GetHTTPErrorStatusCode(err error) int {
if err == nil {
logrus.WithFields(logrus.Fields{"error": err}).Error("unexpected HTTP error handling")
return http.StatusInternalServerError
}
var statusCode int
errMsg := err.Error()
switch e := err.(type) {
case httpStatusError:
statusCode = e.HTTPErrorStatusCode()
case inputValidationError:
statusCode = http.StatusBadRequest
default:
statusCode = statusCodeFromGRPCError(err)
if statusCode != http.StatusInternalServerError {
return statusCode
}
// FIXME: this is brittle and should not be necessary, but we still need to identify if
// there are errors falling back into this logic.
// If we need to differentiate between different possible error types,
// we should create appropriate error types that implement the httpStatusError interface.
errStr := strings.ToLower(errMsg)
for _, status := range []struct {
keyword string
code int
}{
{"not found", http.StatusNotFound},
{"cannot find", http.StatusNotFound},
{"no such", http.StatusNotFound},
{"bad parameter", http.StatusBadRequest},
{"no command", http.StatusBadRequest},
{"conflict", http.StatusConflict},
{"impossible", http.StatusNotAcceptable},
{"wrong login/password", http.StatusUnauthorized},
{"unauthorized", http.StatusUnauthorized},
{"hasn't been activated", http.StatusForbidden},
{"this node", http.StatusServiceUnavailable},
{"needs to be unlocked", http.StatusServiceUnavailable},
{"certificates have expired", http.StatusServiceUnavailable},
{"repository does not exist", http.StatusNotFound},
} {
if strings.Contains(errStr, status.keyword) {
statusCode = status.code
break
}
}
}
if statusCode == 0 {
statusCode = http.StatusInternalServerError
}
return statusCode
}
func apiVersionSupportsJSONErrors(version string) bool {
const firstAPIVersionWithJSONErrors = "1.23"
return version == "" || versions.GreaterThan(version, firstAPIVersionWithJSONErrors)
}
// MakeErrorHandler makes an HTTP handler that decodes a Docker error and
// returns it in the response.
func MakeErrorHandler(err error) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
statusCode := GetHTTPErrorStatusCode(err)
vars := mux.Vars(r)
if apiVersionSupportsJSONErrors(vars["version"]) {
response := &types.ErrorResponse{
Message: err.Error(),
}
WriteJSON(w, statusCode, response)
} else {
http.Error(w, grpc.ErrorDesc(err), statusCode)
}
}
}
// statusCodeFromGRPCError returns status code according to gRPC error
func statusCodeFromGRPCError(err error) int {
switch grpc.Code(err) {
case codes.InvalidArgument: // code 3
return http.StatusBadRequest
case codes.NotFound: // code 5
return http.StatusNotFound
case codes.AlreadyExists: // code 6
return http.StatusConflict
case codes.PermissionDenied: // code 7
return http.StatusForbidden
case codes.FailedPrecondition: // code 9
return http.StatusBadRequest
case codes.Unauthenticated: // code 16
return http.StatusUnauthorized
case codes.OutOfRange: // code 11
return http.StatusBadRequest
case codes.Unimplemented: // code 12
return http.StatusNotImplemented
case codes.Unavailable: // code 14
return http.StatusServiceUnavailable
default:
// codes.Canceled(1)
// codes.Unknown(2)
// codes.DeadlineExceeded(4)
// codes.ResourceExhausted(8)
// codes.Aborted(10)
// codes.Internal(13)
// codes.DataLoss(15)
return http.StatusInternalServerError
}
}
|
