// Middleware sets up the request context so account information can be
// retrieved with auth.GetAccount(ctx). It panics if config.Get(ctx) fails.
func Middleware(ctx context.Context, w http.ResponseWriter, r *http.Request) context.Context {
var conf config.Global
if err := config.Get(ctx, &conf); err != nil {
panic("Could not get AuthSecret: " + err.Error())
} else if claimSet, err := Decode([]byte(r.Header.Get("Authorization")), []byte(conf.AuthSecret)); err != nil {
ctx = context.WithValue(ctx, internal.ClaimSetContextKey, err)
return context.WithValue(ctx, internal.AuthContextKey, err)
} else if claimSet == SuperClaimSet {
ctx = context.WithValue(ctx, internal.ClaimSetContextKey, SuperClaimSet)
return context.WithValue(ctx, internal.AuthContextKey, &account.Super)
} else if claimSet == NobodyClaimSet {
ctx = context.WithValue(ctx, internal.ClaimSetContextKey, NobodyClaimSet)
return context.WithValue(ctx, internal.AuthContextKey, &account.Nobody)
} else {
var acct account.Account
if err := account.Get(ctx, claimSet.Sub, &acct); err != nil {
rest.WriteJSON(w, &rest.Response{
Code: http.StatusUnauthorized,
Body: &rest.Message{"Could not retrieve account with key " + claimSet.Sub + ": " + err.Error()},
})
return nil
} else {
ctx = context.WithValue(ctx, internal.ClaimSetContextKey, claimSet)
return context.WithValue(ctx, internal.AuthContextKey, &acct)
}
}
}
func getConfig(ctx context.Context, w http.ResponseWriter, r *http.Request) {
conf := config.Config{}
if err := config.Get(ctx, &conf); err != nil {
rest.WriteJSON(w, err)
} else {
rest.WriteJSON(w, &conf)
}
}
func changeConfig(ctx context.Context, w http.ResponseWriter, r *http.Request) {
conf := config.Config{}
if err := config.Get(ctx, &conf); err != nil {
rest.WriteJSON(w, err)
} else if err := rest.ReadJSON(r, &conf); err != nil {
rest.WriteJSON(w, err)
} else if err := config.Save(ctx, &conf); err != nil {
rest.WriteJSON(w, err)
} else {
rest.WriteJSON(w, &conf)
}
}
func getJwt(ctx context.Context, w http.ResponseWriter, r *http.Request) {
var acct account.Account
var email string
var err error
conf := config.Global{}
if err := config.Get(ctx, &conf); err != nil {
rest.WriteJSON(w, err)
return
}
// read the account ID
if emailBytes, err := base64.RawURLEncoding.DecodeString(rest.Param(ctx, "id")); err != nil {
rest.WriteJSON(w, err)
return
} else {
email = string(emailBytes)
}
if err = account.Get(ctx, email, &acct); err != nil {
rest.WriteJSON(w, err)
return
}
// All set. Generate the JWT.
jwt, err := auth.Encode(&jws.ClaimSet{
Sub: acct.Email,
Scope: strings.Join(acct.Roles, ","),
Exp: time.Now().AddDate(1, 0, 0).Unix(),
PrivateClaims: map[string]interface{}{
"n": "DEV USER",
},
}, []byte(conf.AuthSecret))
if err != nil {
rest.WriteJSON(w, errors.New(http.StatusInternalServerError, "Could not generate JWT"))
return
} else {
jwtString := string(jwt)
rest.WriteJSON(w, &jwtString)
return
}
}
// Middleware ensures all requests are formatted properly for a REST/JSON API.
// It requires that inbound requests meet all of the following conditions:
//
// The request accepts application/json.
// The request's content type is application/json, if it has a body.
// The request is encoded in UTF-8.
// The request accepts UTF-8.
// The request is properly configured for CORS, if it requires it.
//
// If any of these conditions is not met, Rest will respond with an appropriate
// HTTP error code and error message. Otherwise it will pass control down the line.
func Middleware(ctx context.Context, w http.ResponseWriter, r *http.Request) context.Context {
w.Header().Set("Accept", "application/json")
w.Header().Set("Accept-Charset", "UTF-8")
w.Header().Set("Content-Type", "application/json; charset=UTF-8")
w.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PATCH, DELETE")
var conf config.Global
if err := config.Get(ctx, &conf); err != nil {
panic("Could not retrieve Configuration for Rest middleware: " + err.Error())
}
if !AcceptsJson(r) || !AcceptsUtf8(r) {
// If the requester does not accept JSON in the UTF-8 character set, respond with
// 406 Not Acceptable
w.WriteHeader(http.StatusNotAcceptable)
w.Write([]byte(`{"message": "This API only responds with application/json in UTF-8"}`))
return nil
} else if r.Method != "HEAD" && r.Method != "GET" && r.Method != "OPTIONS" && !ContentIsJson(r) {
// If the requester has sent something other than application/json, respond with
// 415 Unsupported Media Type
w.WriteHeader(http.StatusUnsupportedMediaType)
w.Write([]byte(`{"message": "This API only accepts application/json in UTF-8"}`))
return nil
} else if r.Header.Get("Origin") != "" && !HasValidOrigin(r, conf.ValidOriginSuffix) {
// If the requester has sent Origin and the origin is invalid, respond with
// 400 Bad Request
w.Header().Set("Access-Control-Allow-Origin", conf.ValidOriginSuffix)
w.WriteHeader(http.StatusBadRequest)
fmt.Fprintf(w, `{"message": "Invalid Origin header; this API only accepts %s and its subdomains"}`, conf.ValidOriginSuffix)
return nil
} else {
// The request passes all checks; it can now be processed
// Since "Access-Control-Allow-Origin" passed, set the request Origin
// as an allowed origin
if r.Header.Get("Origin") != "" {
w.Header().Set("Access-Control-Allow-Origin", r.Header.Get("Origin"))
w.Header().Set("Access-Control-Allow-Credentials", "true")
}
if r.Method == "OPTIONS" {
// Options call. Intercept and do not forward.
w.Header().Set("Access-Control-Allow-Headers", "Accept, Accept-Charset, Content-Type, Authorization, X-CORS")
w.Header().Set("Access-Control-Expose-Headers", "Content-Type, Accept, Accept-Charset, Link, Location, X-CORS")
w.Header().Set("Access-Control-Max-Age", "3600")
w.WriteHeader(http.StatusNoContent)
return nil
}
return ctx
}
}