Merge branch '16773-webshell-js' into 16796-arvbox-webshell
[arvados.git] / services / keep-web / s3.go
index c6f501e492e6b5f627e9dbae79ec12aec98b1214..4e8028ae6e8de3c429679c7ff25fc87ee58f3cf2 100644 (file)
@@ -5,13 +5,24 @@
 package main
 
 import (
+       "encoding/xml"
+       "errors"
        "fmt"
        "io"
        "net/http"
        "os"
+       "path/filepath"
+       "sort"
+       "strconv"
        "strings"
+
+       "git.arvados.org/arvados.git/sdk/go/arvados"
+       "git.arvados.org/arvados.git/sdk/go/ctxlog"
+       "github.com/AdRoll/goamz/s3"
 )
 
+const s3MaxKeys = 1000
+
 // serveS3 handles r and returns true if r is a request from an S3
 // client, otherwise it returns false.
 func (h *handler) serveS3(w http.ResponseWriter, r *http.Request) bool {
@@ -24,9 +35,22 @@ func (h *handler) serveS3(w http.ResponseWriter, r *http.Request) bool {
                }
                token = split[0]
        } else if strings.HasPrefix(auth, "AWS4-HMAC-SHA256 ") {
-               w.WriteHeader(http.StatusBadRequest)
-               fmt.Println(w, "V4 signature is not supported")
-               return true
+               for _, cmpt := range strings.Split(auth[17:], ",") {
+                       cmpt = strings.TrimSpace(cmpt)
+                       split := strings.SplitN(cmpt, "=", 2)
+                       if len(split) == 2 && split[0] == "Credential" {
+                               keyandscope := strings.Split(split[1], "/")
+                               if len(keyandscope[0]) > 0 {
+                                       token = keyandscope[0]
+                                       break
+                               }
+                       }
+               }
+               if token == "" {
+                       w.WriteHeader(http.StatusBadRequest)
+                       fmt.Println(w, "invalid V4 signature")
+                       return true
+               }
        } else {
                return false
        }
@@ -38,58 +62,187 @@ func (h *handler) serveS3(w http.ResponseWriter, r *http.Request) bool {
        }
        defer release()
 
-       r.URL.Path = "/by_id" + r.URL.Path
-
        fs := client.SiteFileSystem(kc)
        fs.ForwardSlashNameSubstitution(h.Config.cluster.Collections.ForwardSlashNameSubstitution)
 
-       switch r.Method {
-       case "GET":
-               fi, err := fs.Stat(r.URL.Path)
-               if os.IsNotExist(err) {
-                       http.Error(w, err.Error(), http.StatusNotFound)
+       objectNameGiven := strings.Count(strings.TrimSuffix(r.URL.Path, "/"), "/") > 1
+
+       switch {
+       case r.Method == http.MethodGet && !objectNameGiven:
+               // Path is "/{uuid}" or "/{uuid}/", has no object name
+               if _, ok := r.URL.Query()["versioning"]; ok {
+                       // GetBucketVersioning
+                       w.Header().Set("Content-Type", "application/xml")
+                       io.WriteString(w, xml.Header)
+                       fmt.Fprintln(w, `<VersioningConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/"/>`)
+               } else {
+                       // ListObjects
+                       h.s3list(w, r, fs)
+               }
+               return true
+       case r.Method == http.MethodGet || r.Method == http.MethodHead:
+               fspath := "/by_id" + r.URL.Path
+               fi, err := fs.Stat(fspath)
+               if r.Method == "HEAD" && !objectNameGiven {
+                       // HeadBucket
+                       if err == nil && fi.IsDir() {
+                               w.WriteHeader(http.StatusOK)
+                       } else if os.IsNotExist(err) {
+                               w.WriteHeader(http.StatusNotFound)
+                       } else {
+                               http.Error(w, err.Error(), http.StatusBadGateway)
+                       }
                        return true
-               } else if err != nil {
-                       http.Error(w, err.Error(), http.StatusInternalServerError)
+               }
+               if err == nil && fi.IsDir() && objectNameGiven && strings.HasSuffix(fspath, "/") && h.Config.cluster.Collections.S3FolderObjects {
+                       w.Header().Set("Content-Type", "application/x-directory")
+                       w.WriteHeader(http.StatusOK)
                        return true
-               } else if fi.IsDir() {
+               }
+               if os.IsNotExist(err) ||
+                       (err != nil && err.Error() == "not a directory") ||
+                       (fi != nil && fi.IsDir()) {
                        http.Error(w, "not found", http.StatusNotFound)
+                       return true
                }
-               http.FileServer(fs).ServeHTTP(w, r)
+               // shallow copy r, and change URL path
+               r := *r
+               r.URL.Path = fspath
+               http.FileServer(fs).ServeHTTP(w, &r)
                return true
-       case "PUT":
-               f, err := fs.OpenFile(r.URL.Path, os.O_WRONLY|os.O_TRUNC|os.O_CREATE, 0644)
-               if os.IsNotExist(err) {
-                       // create missing intermediate directories, then try again
-                       for i, c := range r.URL.Path {
-                               if i > 0 && c == '/' {
-                                       dir := r.URL.Path[:i]
-                                       err := fs.Mkdir(dir, 0755)
-                                       if err != nil && err != os.ErrExist {
-                                               err = fmt.Errorf("mkdir %q failed: %w", dir, err)
-                                               http.Error(w, err.Error(), http.StatusInternalServerError)
-                                               return true
-                                       }
+       case r.Method == http.MethodPut:
+               if !objectNameGiven {
+                       http.Error(w, "missing object name in PUT request", http.StatusBadRequest)
+                       return true
+               }
+               fspath := "by_id" + r.URL.Path
+               var objectIsDir bool
+               if strings.HasSuffix(fspath, "/") {
+                       if !h.Config.cluster.Collections.S3FolderObjects {
+                               http.Error(w, "invalid object name: trailing slash", http.StatusBadRequest)
+                               return true
+                       }
+                       n, err := r.Body.Read(make([]byte, 1))
+                       if err != nil && err != io.EOF {
+                               http.Error(w, fmt.Sprintf("error reading request body: %s", err), http.StatusInternalServerError)
+                               return true
+                       } else if n > 0 {
+                               http.Error(w, "cannot create object with trailing '/' char unless content is empty", http.StatusBadRequest)
+                               return true
+                       } else if strings.SplitN(r.Header.Get("Content-Type"), ";", 2)[0] != "application/x-directory" {
+                               http.Error(w, "cannot create object with trailing '/' char unless Content-Type is 'application/x-directory'", http.StatusBadRequest)
+                               return true
+                       }
+                       // Given PUT "foo/bar/", we'll use "foo/bar/."
+                       // in the "ensure parents exist" block below,
+                       // and then we'll be done.
+                       fspath += "."
+                       objectIsDir = true
+               }
+               fi, err := fs.Stat(fspath)
+               if err != nil && err.Error() == "not a directory" {
+                       // requested foo/bar, but foo is a file
+                       http.Error(w, "object name conflicts with existing object", http.StatusBadRequest)
+                       return true
+               }
+               if strings.HasSuffix(r.URL.Path, "/") && err == nil && !fi.IsDir() {
+                       // requested foo/bar/, but foo/bar is a file
+                       http.Error(w, "object name conflicts with existing object", http.StatusBadRequest)
+                       return true
+               }
+               // create missing parent/intermediate directories, if any
+               for i, c := range fspath {
+                       if i > 0 && c == '/' {
+                               dir := fspath[:i]
+                               if strings.HasSuffix(dir, "/") {
+                                       err = errors.New("invalid object name (consecutive '/' chars)")
+                                       http.Error(w, err.Error(), http.StatusBadRequest)
+                                       return true
+                               }
+                               err = fs.Mkdir(dir, 0755)
+                               if err == arvados.ErrInvalidArgument {
+                                       // Cannot create a directory
+                                       // here.
+                                       err = fmt.Errorf("mkdir %q failed: %w", dir, err)
+                                       http.Error(w, err.Error(), http.StatusBadRequest)
+                                       return true
+                               } else if err != nil && !os.IsExist(err) {
+                                       err = fmt.Errorf("mkdir %q failed: %w", dir, err)
+                                       http.Error(w, err.Error(), http.StatusInternalServerError)
+                                       return true
                                }
                        }
-                       f, err = fs.OpenFile(r.URL.Path, os.O_WRONLY|os.O_TRUNC|os.O_CREATE, 0644)
                }
+               if !objectIsDir {
+                       f, err := fs.OpenFile(fspath, os.O_WRONLY|os.O_TRUNC|os.O_CREATE, 0644)
+                       if os.IsNotExist(err) {
+                               f, err = fs.OpenFile(fspath, os.O_WRONLY|os.O_TRUNC|os.O_CREATE, 0644)
+                       }
+                       if err != nil {
+                               err = fmt.Errorf("open %q failed: %w", r.URL.Path, err)
+                               http.Error(w, err.Error(), http.StatusBadRequest)
+                               return true
+                       }
+                       defer f.Close()
+                       _, err = io.Copy(f, r.Body)
+                       if err != nil {
+                               err = fmt.Errorf("write to %q failed: %w", r.URL.Path, err)
+                               http.Error(w, err.Error(), http.StatusBadGateway)
+                               return true
+                       }
+                       err = f.Close()
+                       if err != nil {
+                               err = fmt.Errorf("write to %q failed: close: %w", r.URL.Path, err)
+                               http.Error(w, err.Error(), http.StatusBadGateway)
+                               return true
+                       }
+               }
+               err = fs.Sync()
                if err != nil {
-                       err = fmt.Errorf("open %q failed: %w", r.URL.Path, err)
-                       http.Error(w, err.Error(), http.StatusBadRequest)
+                       err = fmt.Errorf("sync failed: %w", err)
+                       http.Error(w, err.Error(), http.StatusInternalServerError)
                        return true
                }
-               defer f.Close()
-               _, err = io.Copy(f, r.Body)
-               if err != nil {
-                       err = fmt.Errorf("write to %q failed: %w", r.URL.Path, err)
-                       http.Error(w, err.Error(), http.StatusBadGateway)
+               w.WriteHeader(http.StatusOK)
+               return true
+       case r.Method == http.MethodDelete:
+               if !objectNameGiven || r.URL.Path == "/" {
+                       http.Error(w, "missing object name in DELETE request", http.StatusBadRequest)
+                       return true
+               }
+               fspath := "by_id" + r.URL.Path
+               if strings.HasSuffix(fspath, "/") {
+                       fspath = strings.TrimSuffix(fspath, "/")
+                       fi, err := fs.Stat(fspath)
+                       if os.IsNotExist(err) {
+                               w.WriteHeader(http.StatusNoContent)
+                               return true
+                       } else if err != nil {
+                               http.Error(w, err.Error(), http.StatusInternalServerError)
+                               return true
+                       } else if !fi.IsDir() {
+                               // if "foo" exists and is a file, then
+                               // "foo/" doesn't exist, so we say
+                               // delete was successful.
+                               w.WriteHeader(http.StatusNoContent)
+                               return true
+                       }
+               } else if fi, err := fs.Stat(fspath); err == nil && fi.IsDir() {
+                       // if "foo" is a dir, it is visible via S3
+                       // only as "foo/", not "foo" -- so we leave
+                       // the dir alone and return 204 to indicate
+                       // that "foo" does not exist.
+                       w.WriteHeader(http.StatusNoContent)
+                       return true
+               }
+               err = fs.Remove(fspath)
+               if os.IsNotExist(err) {
+                       w.WriteHeader(http.StatusNoContent)
                        return true
                }
-               err = f.Close()
                if err != nil {
-                       err = fmt.Errorf("write to %q failed: %w", r.URL.Path, err)
-                       http.Error(w, err.Error(), http.StatusBadGateway)
+                       err = fmt.Errorf("rm failed: %w", err)
+                       http.Error(w, err.Error(), http.StatusBadRequest)
                        return true
                }
                err = fs.Sync()
@@ -98,10 +251,212 @@ func (h *handler) serveS3(w http.ResponseWriter, r *http.Request) bool {
                        http.Error(w, err.Error(), http.StatusInternalServerError)
                        return true
                }
-               w.WriteHeader(http.StatusOK)
+               w.WriteHeader(http.StatusNoContent)
                return true
        default:
                http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
                return true
        }
 }
+
+// Call fn on the given path (directory) and its contents, in
+// lexicographic order.
+//
+// If isRoot==true and path is not a directory, return nil.
+//
+// If fn returns filepath.SkipDir when called on a directory, don't
+// descend into that directory.
+func walkFS(fs arvados.CustomFileSystem, path string, isRoot bool, fn func(path string, fi os.FileInfo) error) error {
+       if isRoot {
+               fi, err := fs.Stat(path)
+               if os.IsNotExist(err) || (err == nil && !fi.IsDir()) {
+                       return nil
+               } else if err != nil {
+                       return err
+               }
+               err = fn(path, fi)
+               if err == filepath.SkipDir {
+                       return nil
+               } else if err != nil {
+                       return err
+               }
+       }
+       f, err := fs.Open(path)
+       if os.IsNotExist(err) && isRoot {
+               return nil
+       } else if err != nil {
+               return fmt.Errorf("open %q: %w", path, err)
+       }
+       defer f.Close()
+       if path == "/" {
+               path = ""
+       }
+       fis, err := f.Readdir(-1)
+       if err != nil {
+               return err
+       }
+       sort.Slice(fis, func(i, j int) bool { return fis[i].Name() < fis[j].Name() })
+       for _, fi := range fis {
+               err = fn(path+"/"+fi.Name(), fi)
+               if err == filepath.SkipDir {
+                       continue
+               } else if err != nil {
+                       return err
+               }
+               if fi.IsDir() {
+                       err = walkFS(fs, path+"/"+fi.Name(), false, fn)
+                       if err != nil {
+                               return err
+                       }
+               }
+       }
+       return nil
+}
+
+var errDone = errors.New("done")
+
+func (h *handler) s3list(w http.ResponseWriter, r *http.Request, fs arvados.CustomFileSystem) {
+       var params struct {
+               bucket    string
+               delimiter string
+               marker    string
+               maxKeys   int
+               prefix    string
+       }
+       params.bucket = strings.SplitN(r.URL.Path[1:], "/", 2)[0]
+       params.delimiter = r.FormValue("delimiter")
+       params.marker = r.FormValue("marker")
+       if mk, _ := strconv.ParseInt(r.FormValue("max-keys"), 10, 64); mk > 0 && mk < s3MaxKeys {
+               params.maxKeys = int(mk)
+       } else {
+               params.maxKeys = s3MaxKeys
+       }
+       params.prefix = r.FormValue("prefix")
+
+       bucketdir := "by_id/" + params.bucket
+       // walkpath is the directory (relative to bucketdir) we need
+       // to walk: the innermost directory that is guaranteed to
+       // contain all paths that have the requested prefix. Examples:
+       // prefix "foo/bar"  => walkpath "foo"
+       // prefix "foo/bar/" => walkpath "foo/bar"
+       // prefix "foo"      => walkpath ""
+       // prefix ""         => walkpath ""
+       walkpath := params.prefix
+       if cut := strings.LastIndex(walkpath, "/"); cut >= 0 {
+               walkpath = walkpath[:cut]
+       } else {
+               walkpath = ""
+       }
+
+       type commonPrefix struct {
+               Prefix string
+       }
+       type listResp struct {
+               XMLName string `xml:"http://s3.amazonaws.com/doc/2006-03-01/ ListBucketResult"`
+               s3.ListResp
+               // s3.ListResp marshals an empty tag when
+               // CommonPrefixes is nil, which confuses some clients.
+               // Fix by using this nested struct instead.
+               CommonPrefixes []commonPrefix
+       }
+       resp := listResp{
+               ListResp: s3.ListResp{
+                       Name:      strings.SplitN(r.URL.Path[1:], "/", 2)[0],
+                       Prefix:    params.prefix,
+                       Delimiter: params.delimiter,
+                       Marker:    params.marker,
+                       MaxKeys:   params.maxKeys,
+               },
+       }
+       commonPrefixes := map[string]bool{}
+       err := walkFS(fs, strings.TrimSuffix(bucketdir+"/"+walkpath, "/"), true, func(path string, fi os.FileInfo) error {
+               if path == bucketdir {
+                       return nil
+               }
+               path = path[len(bucketdir)+1:]
+               filesize := fi.Size()
+               if fi.IsDir() {
+                       path += "/"
+                       filesize = 0
+               }
+               if len(path) <= len(params.prefix) {
+                       if path > params.prefix[:len(path)] {
+                               // with prefix "foobar", walking "fooz" means we're done
+                               return errDone
+                       }
+                       if path < params.prefix[:len(path)] {
+                               // with prefix "foobar", walking "foobag" is pointless
+                               return filepath.SkipDir
+                       }
+                       if fi.IsDir() && !strings.HasPrefix(params.prefix+"/", path) {
+                               // with prefix "foo/bar", walking "fo"
+                               // is pointless (but walking "foo" or
+                               // "foo/bar" is necessary)
+                               return filepath.SkipDir
+                       }
+                       if len(path) < len(params.prefix) {
+                               // can't skip anything, and this entry
+                               // isn't in the results, so just
+                               // continue descent
+                               return nil
+                       }
+               } else {
+                       if path[:len(params.prefix)] > params.prefix {
+                               // with prefix "foobar", nothing we
+                               // see after "foozzz" is relevant
+                               return errDone
+                       }
+               }
+               if path < params.marker || path < params.prefix {
+                       return nil
+               }
+               if fi.IsDir() && !h.Config.cluster.Collections.S3FolderObjects {
+                       // Note we don't add anything to
+                       // commonPrefixes here even if delimiter is
+                       // "/". We descend into the directory, and
+                       // return a commonPrefix only if we end up
+                       // finding a regular file inside it.
+                       return nil
+               }
+               if params.delimiter != "" {
+                       idx := strings.Index(path[len(params.prefix):], params.delimiter)
+                       if idx >= 0 {
+                               // with prefix "foobar" and delimiter
+                               // "z", when we hit "foobar/baz", we
+                               // add "/baz" to commonPrefixes and
+                               // stop descending.
+                               commonPrefixes[path[:len(params.prefix)+idx+1]] = true
+                               return filepath.SkipDir
+                       }
+               }
+               if len(resp.Contents)+len(commonPrefixes) >= params.maxKeys {
+                       resp.IsTruncated = true
+                       if params.delimiter != "" {
+                               resp.NextMarker = path
+                       }
+                       return errDone
+               }
+               resp.Contents = append(resp.Contents, s3.Key{
+                       Key:          path,
+                       LastModified: fi.ModTime().UTC().Format("2006-01-02T15:04:05.999") + "Z",
+                       Size:         filesize,
+               })
+               return nil
+       })
+       if err != nil && err != errDone {
+               http.Error(w, err.Error(), http.StatusInternalServerError)
+               return
+       }
+       if params.delimiter != "" {
+               resp.CommonPrefixes = make([]commonPrefix, 0, len(commonPrefixes))
+               for prefix := range commonPrefixes {
+                       resp.CommonPrefixes = append(resp.CommonPrefixes, commonPrefix{prefix})
+               }
+               sort.Slice(resp.CommonPrefixes, func(i, j int) bool { return resp.CommonPrefixes[i].Prefix < resp.CommonPrefixes[j].Prefix })
+       }
+       w.Header().Set("Content-Type", "application/xml")
+       io.WriteString(w, xml.Header)
+       if err := xml.NewEncoder(w).Encode(resp); err != nil {
+               ctxlog.FromContext(r.Context()).WithError(err).Error("error writing xml response")
+       }
+}