minio/generic-handlers.go
2016-02-27 19:51:59 -08:00

301 lines
8.6 KiB
Go

/*
* Minio Cloud Storage, (C) 2015 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package main
import (
"errors"
"net/http"
"path"
"regexp"
"strings"
"time"
router "github.com/gorilla/mux"
"github.com/rs/cors"
)
const (
iso8601Format = "20060102T150405Z"
privateBucket = "/minio"
)
// HandlerFunc - useful to chain different middleware http.Handler
type HandlerFunc func(http.Handler) http.Handler
func registerHandlers(mux *router.Router, handlerFns ...HandlerFunc) http.Handler {
var f http.Handler
f = mux
for _, hFn := range handlerFns {
f = hFn(f)
}
return f
}
// Attempts to parse date string into known date layouts. Date layouts
// currently supported are ``time.RFC1123``, ``time.RFC1123Z`` and
// special ``iso8601Format``.
func parseKnownLayouts(date string) (time.Time, error) {
parsedTime, e := time.Parse(time.RFC1123, date)
if e == nil {
return parsedTime, nil
}
parsedTime, e = time.Parse(time.RFC1123Z, date)
if e == nil {
return parsedTime, nil
}
parsedTime, e = time.Parse(iso8601Format, date)
if e == nil {
return parsedTime, nil
}
return time.Time{}, e
}
// Parse date string from incoming header, current supports and verifies
// follow HTTP headers.
//
// - X-Amz-Date
// - X-Minio-Date
// - Date
//
// In following time layouts ``time.RFC1123``, ``time.RFC1123Z`` and ``iso8601Format``.
func parseDateHeader(req *http.Request) (time.Time, error) {
amzDate := req.Header.Get(http.CanonicalHeaderKey("x-amz-date"))
if amzDate != "" {
return parseKnownLayouts(amzDate)
}
minioDate := req.Header.Get(http.CanonicalHeaderKey("x-minio-date"))
if minioDate != "" {
return parseKnownLayouts(minioDate)
}
genericDate := req.Header.Get("Date")
if genericDate != "" {
return parseKnownLayouts(genericDate)
}
return time.Time{}, errors.New("Date header missing, invalid request.")
}
// Adds redirect rules for incoming requests.
type redirectHandler struct {
handler http.Handler
locationPrefix string
}
func setBrowserRedirectHandler(h http.Handler) http.Handler {
return redirectHandler{handler: h, locationPrefix: privateBucket}
}
func (h redirectHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Re-direction handled specifically for browsers.
if strings.Contains(r.Header.Get("User-Agent"), "Mozilla") {
// '/' is redirected to 'locationPrefix/'
// '/rpc' is redirected to 'locationPrefix/rpc'
// '/login' is redirected to 'locationPrefix/login'
switch r.URL.Path {
case "/", "/rpc", "/login", "/favicon.ico":
location := h.locationPrefix + r.URL.Path
// Redirect to new location.
http.Redirect(w, r, location, http.StatusTemporaryRedirect)
return
}
}
h.handler.ServeHTTP(w, r)
}
// Adds Cache-Control header
type cacheControlHandler struct {
handler http.Handler
}
func setBrowserCacheControlHandler(h http.Handler) http.Handler {
return cacheControlHandler{h}
}
func (h cacheControlHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if r.Method == "GET" && strings.Contains(r.Header.Get("User-Agent"), "Mozilla") {
// For all browser requests set appropriate Cache-Control policies
match, e := regexp.MatchString(privateBucket+`/([^/]+\.js|favicon.ico)`, r.URL.Path)
if e != nil {
writeErrorResponse(w, r, InternalError, r.URL.Path)
return
}
if match {
// For assets set cache expiry of one year. For each release, the name
// of the asset name will change and hence it can not be served from cache.
w.Header().Set("Cache-Control", "max-age=31536000")
} else if strings.HasPrefix(r.URL.Path, privateBucket+"/") {
// For non asset requests we serve index.html which will never be cached.
w.Header().Set("Cache-Control", "no-store")
}
}
h.handler.ServeHTTP(w, r)
}
// Adds verification for incoming paths.
type minioPrivateBucketHandler struct {
handler http.Handler
privateBucket string
}
func setPrivateBucketHandler(h http.Handler) http.Handler {
return minioPrivateBucketHandler{handler: h, privateBucket: privateBucket}
}
func (h minioPrivateBucketHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// For all non browser requests, reject access to 'privateBucket'.
if !strings.Contains(r.Header.Get("User-Agent"), "Mozilla") && path.Clean(r.URL.Path) == privateBucket {
writeErrorResponse(w, r, AllAccessDisabled, r.URL.Path)
return
}
h.handler.ServeHTTP(w, r)
}
type timeHandler struct {
handler http.Handler
}
// setTimeValidityHandler to validate parsable time over http header
func setTimeValidityHandler(h http.Handler) http.Handler {
return timeHandler{h}
}
func (h timeHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Verify if date headers are set, if not reject the request
if r.Header.Get("Authorization") != "" {
date, e := parseDateHeader(r)
if e != nil {
// All our internal APIs are sensitive towards Date
// header, for all requests where Date header is not
// present we will reject such clients.
writeErrorResponse(w, r, RequestTimeTooSkewed, r.URL.Path)
return
}
duration := time.Since(date)
minutes := time.Duration(5) * time.Minute
// Verify if the request date header is more than 5minutes
// late, reject such clients.
if duration.Minutes() > minutes.Minutes() {
writeErrorResponse(w, r, RequestTimeTooSkewed, r.URL.Path)
return
}
}
h.handler.ServeHTTP(w, r)
}
type resourceHandler struct {
handler http.Handler
}
// setCorsHandler handler for CORS (Cross Origin Resource Sharing)
func setCorsHandler(h http.Handler) http.Handler {
c := cors.New(cors.Options{
AllowedOrigins: []string{"*"},
AllowedMethods: []string{"GET", "HEAD", "POST", "PUT"},
AllowedHeaders: []string{"*"},
})
return c.Handler(h)
}
// setIgnoreResourcesHandler -
// Ignore resources handler is wrapper handler used for API request resource validation
// Since we do not support all the S3 queries, it is necessary for us to throw back a
// valid error message indicating that requested feature is not implemented.
func setIgnoreResourcesHandler(h http.Handler) http.Handler {
return resourceHandler{h}
}
// Resource handler ServeHTTP() wrapper
func (h resourceHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
// Skip the first element which is usually '/' and split the rest.
splits := strings.SplitN(r.URL.Path[1:], "/", 2)
// Save bucketName and objectName extracted from url Path.
var bucketName, objectName string
if len(splits) == 1 {
bucketName = splits[0]
}
if len(splits) == 2 {
bucketName = splits[0]
objectName = splits[1]
}
// If bucketName is present and not objectName check for bucket
// level resource queries.
if bucketName != "" && objectName == "" {
if ignoreNotImplementedBucketResources(r) {
writeErrorResponse(w, r, NotImplemented, r.URL.Path)
return
}
}
// If bucketName and objectName are present check for its resource queries.
if bucketName != "" && objectName != "" {
if ignoreNotImplementedObjectResources(r) {
writeErrorResponse(w, r, NotImplemented, r.URL.Path)
return
}
}
// A put method on path "/" doesn't make sense, ignore it.
if r.Method == "PUT" && r.URL.Path == "/" {
writeErrorResponse(w, r, NotImplemented, r.URL.Path)
return
}
h.handler.ServeHTTP(w, r)
}
//// helpers
// Checks requests for not implemented Bucket resources
func ignoreNotImplementedBucketResources(req *http.Request) bool {
for name := range req.URL.Query() {
if notimplementedBucketResourceNames[name] {
return true
}
}
return false
}
// Checks requests for not implemented Object resources
func ignoreNotImplementedObjectResources(req *http.Request) bool {
for name := range req.URL.Query() {
if notimplementedObjectResourceNames[name] {
return true
}
}
return false
}
// List of not implemented bucket queries
var notimplementedBucketResourceNames = map[string]bool{
"policy": true,
"cors": true,
"lifecycle": true,
"logging": true,
"notification": true,
"replication": true,
"tagging": true,
"versions": true,
"requestPayment": true,
"versioning": true,
"website": true,
"delete": true,
}
// List of not implemented object queries
var notimplementedObjectResourceNames = map[string]bool{
"torrent": true,
"acl": true,
"policy": true,
}