package providers import ( "encoding/base64" "net/url" "strings" "github.com/bitly/go-simplejson" ) type GoogleProvider struct { *ProviderData } func NewGoogleProvider(p *ProviderData) *GoogleProvider { p.ProviderName = "Google" if p.LoginUrl.String() == "" { p.LoginUrl = &url.URL{Scheme: "https", Host: "accounts.google.com", Path: "/o/oauth2/auth"} } if p.RedeemUrl.String() == "" { p.RedeemUrl = &url.URL{Scheme: "https", Host: "accounts.google.com", Path: "/o/oauth2/token"} } if p.ValidateUrl.String() == "" { p.ValidateUrl = &url.URL{Scheme: "https", Host: "www.googleapis.com", Path: "/oauth2/v1/tokeninfo"} } if p.Scope == "" { p.Scope = "profile email" } return &GoogleProvider{ProviderData: p} } func (s *GoogleProvider) GetEmailAddress(auth_response *simplejson.Json, unused_access_token string) (string, error) { idToken, err := auth_response.Get("id_token").String() if err != nil { return "", err } // id_token is a base64 encode ID token payload // https://developers.google.com/accounts/docs/OAuth2Login#obtainuserinfo jwt := strings.Split(idToken, ".") b, err := jwtDecodeSegment(jwt[1]) if err != nil { return "", err } data, err := simplejson.NewJson(b) if err != nil { return "", err } email, err := data.Get("email").String() if err != nil { return "", err } return email, nil } func jwtDecodeSegment(seg string) ([]byte, error) { if l := len(seg) % 4; l > 0 { seg += strings.Repeat("=", 4-l) } return base64.URLEncoding.DecodeString(seg) }