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
|
// Copyright 2019 Canonical Ltd.
// Licensed under the LGPLv3, see LICENCE.client file for details.
// Package redirect implements redirection based login.
package redirect
import (
"context"
"net/url"
"strings"
"github.com/go-macaroon-bakery/macaroon-bakery/v3/httpbakery"
errgo "gopkg.in/errgo.v1"
httprequest "gopkg.in/httprequest.v1"
"github.com/canonical/candid/params"
)
const Kind = "browser-redirect"
type InteractionInfo struct {
// LoginURL contains the URL to redirect to in order to start a
// login attempt.
LoginURL string
// DischargeTokenURL contains the URL that is used to swap a
// login code for a discharge token.
DischargeTokenURL string
}
// RedirectURL calculates the URL to redirect to in order to initate a
// browser-redirect login.
func (i InteractionInfo) RedirectURL(returnTo, state string) string {
v := make(url.Values, 2)
v.Set("return_to", returnTo)
v.Set("state", state)
var sb strings.Builder
sb.WriteString(i.LoginURL)
if strings.Contains(i.LoginURL, "?") {
sb.WriteByte('&')
} else {
sb.WriteByte('?')
}
sb.WriteString(v.Encode())
return sb.String()
}
// SetInteraction adds interaction info the the browser-redirect interaction type.
func SetInteraction(ierr *httpbakery.Error, loginURL, dischargeTokenURL string) {
ierr.SetInteraction(Kind, InteractionInfo{
LoginURL: loginURL,
DischargeTokenURL: dischargeTokenURL,
})
}
// DischargeTokenRequest represents a request to the DischargeTokenURL.
type DischargeTokenRequest struct {
httprequest.Route `httprequest:"POST"`
Body struct {
Code string `json:"code"`
} `httprequest:",body"`
}
// DischargeTokenResponse contains a response from a DischargeTokenURL.
type DischargeTokenResponse struct {
DischargeToken *httpbakery.DischargeToken `json:"token,omitempty"`
}
// GetDischargeToken retrieves the discharge token associated with the
// given code.
func (i InteractionInfo) GetDischargeToken(ctx context.Context, code string) (*httpbakery.DischargeToken, error) {
client := new(httprequest.Client)
var req DischargeTokenRequest
req.Body.Code = code
var resp DischargeTokenResponse
if err := client.CallURL(ctx, i.DischargeTokenURL, &req, &resp); err != nil {
return nil, errgo.Mask(err)
}
return resp.DischargeToken, nil
}
// ParseLoginResult extracts the result from a response callback.
func ParseLoginResult(requestURL string) (state, code string, err error) {
u, err := url.Parse(requestURL)
if err != nil {
return "", "", errgo.Mask(err)
}
v := u.Query()
if e := v.Get("error"); e != "" {
if ec := v.Get("error_code"); ec != "" {
return v.Get("state"), "", errgo.WithCausef(nil, params.ErrorCode(ec), "%s", e)
}
return v.Get("state"), "", errgo.Newf("%s", e)
}
return v.Get("state"), v.Get("code"), nil
}
type Interactor struct {
dischargeTokens map[string]httpbakery.DischargeToken
}
// Kind implements httpbakery.Interactor.
func (*Interactor) Kind() string {
return Kind
}
// Interact implements httpbakery.Interactor.
func (i *Interactor) Interact(ctx context.Context, _ *httpbakery.Client, _ string, ierr *httpbakery.Error) (*httpbakery.DischargeToken, error) {
var v InteractionInfo
if err := ierr.InteractionMethod(Kind, &v); err != nil {
return nil, errgo.Mask(err, errgo.Is(httpbakery.ErrInteractionMethodNotFound))
}
if dt, ok := i.dischargeTokens[v.LoginURL]; ok {
return &dt, nil
}
return nil, &httpbakery.InteractionError{
Reason: &RedirectRequiredError{
InteractionInfo: v,
},
}
}
// SetDischargeToken sets a discharge token for a particular login URL.
func (i *Interactor) SetDischargeToken(loginURL string, dt *httpbakery.DischargeToken) {
if i.dischargeTokens == nil {
i.dischargeTokens = make(map[string]httpbakery.DischargeToken)
}
if dt == nil {
delete(i.dischargeTokens, loginURL)
} else {
i.dischargeTokens[loginURL] = *dt
}
}
// A RedirectRequiredError is the type of error returned from an
// interactor when an interaction via redirection is required.
type RedirectRequiredError struct {
InteractionInfo InteractionInfo
}
// Error implements error.
func (e RedirectRequiredError) Error() string {
return "redirect required"
}
// IsRedirectRequiredError determines if an error is a
// RedirectRequiredError.
func IsRedirectRequiredError(err error) bool {
_, ok := err.(*RedirectRequiredError)
return ok
}
|
