Working writes

1 files changed, 238 insertions, 91 deletions

diff --git a/main.go b/main.go
index 6bf7f7a..aec59a2 100644
--- a/main.go
+++ b/main.go
@@ -4,8 +4,10 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"io/fs"
 	"log"
+	"mime"
 	"net/http"
 	"os"
 	"path"
@@ -49,11 +51,13 @@ func main() {
 		FileSystem: NewGarageFS(),
 		LockSystem: webdav.NewMemLS(),
 		Logger: func(r *http.Request, err error) {
-			log.Printf("WEBDAV: %#s, ERROR: %v", r, err)
+			log.Printf("INFO: %s %s %s\n", r.RemoteAddr, r.Method, r.URL)
+			if err != nil {
+				log.Printf("ERR: %v", err)
+			}
 		},
 	}
 
-	//http.Handle("/", srv)
 	http.HandleFunc(pathPrefix+"/", func(w http.ResponseWriter, r *http.Request) {
 		username, password, ok := r.BasicAuth()
 
@@ -167,6 +171,7 @@ func (s *GarageFS) Mkdir(ctx context.Context, name string, perm os.FileMode) err
 }
 
 func (s *GarageFS) OpenFile(ctx context.Context, name string, flag int, perm os.FileMode) (webdav.File, error) {
+	NewGarageStatFromFile(ctx, name)
 	return NewGarageFile(ctx, name)
 }
 
@@ -179,71 +184,112 @@ func (s *GarageFS) Rename(ctx context.Context, oldName, newName string) error {
 }
 
 func (s *GarageFS) Stat(ctx context.Context, name string) (os.FileInfo, error) {
+	log.Println("Stat from GarageFS")
 	return NewGarageStat(ctx, name)
 }
 
 type GarageFile struct {
-	ctx  context.Context
-	mc   *minio.Client
-  obj  *minio.Object
-  stat *GarageStat
-	path string
+	ctx   context.Context
+	mc    *minio.Client
+	obj   *minio.Object
+	objw  *io.PipeWriter
+	donew chan error
+	pos   int64
+	path  S3Path
 }
 
 func NewGarageFile(ctx context.Context, path string) (webdav.File, error) {
 	gf := new(GarageFile)
 	gf.ctx = ctx
+	gf.pos = 0
 	gf.mc = ctx.Value(garageEntry).(garageCtx).MC
-	gf.path = path
-  stat, err := NewGarageStat(ctx, path)
-  if err != nil {
-    return nil, err
-  }
-  gf.stat = stat
+	gf.path = NewS3Path(path)
 	return gf, nil
 }
 
 func (gf *GarageFile) Close() error {
-  if gf.obj == nil {
-    return nil
-  }
-  err := gf.obj.Close()
-  gf.obj = nil
-  return err
+	err := make([]error, 0)
+
+	if gf.obj != nil {
+		err = append(err, gf.obj.Close())
+		gf.obj = nil
+	}
+
+	if gf.objw != nil {
+		// wait that minio completes its transfers in background
+		err = append(err, gf.objw.Close())
+		err = append(err, <-gf.donew)
+		gf.donew = nil
+		gf.objw = nil
+	}
+
+	count := 0
+	for _, e := range err {
+		if e != nil {
+			count++
+			log.Println(e)
+		}
+	}
+	if count > 0 {
+		return errors.New(fmt.Sprintf("%d errors when closing this WebDAV File. Read previous logs to know more.", count))
+	}
+	return nil
 }
 
 func (gf *GarageFile) loadObject() error {
-  if gf.obj == nil {
-    log.Println("Called GetObject on", gf.path)
-    obj, err := gf.mc.GetObject(gf.ctx, gf.stat.bucket, gf.stat.obj.Key, minio.GetObjectOptions{})
-    if err != nil {
-      return err
-    }
-    gf.obj = obj
-  }
-  return nil
+	if gf.obj == nil {
+		obj, err := gf.mc.GetObject(gf.ctx, gf.path.bucket, gf.path.key, minio.GetObjectOptions{})
+		if err != nil {
+			return err
+		}
+		gf.obj = obj
+	}
+	return nil
 }
 
 func (gf *GarageFile) Read(p []byte) (n int, err error) {
-	if gf.stat.Mode().IsDir() {
-		return 0, os.ErrInvalid
+	//if gf.Stat() & OBJECT == 0 { /* @FIXME Ideally we would check against OBJECT but we need a non OPAQUE_KEY */
+	//	return 0, os.ErrInvalid
+	//}
+	if err := gf.loadObject(); err != nil {
+		return 0, err
 	}
-  if err := gf.loadObject(); err != nil {
-    return 0, err
-  }
 
-  return gf.obj.Read(p)
+	return gf.obj.Read(p)
 }
 
 func (gf *GarageFile) Write(p []byte) (n int, err error) {
-	return 0, errors.New("not implemented Write")
+	/*if gf.path.class != OBJECT {
+		return 0, os.ErrInvalid
+	}*/
+
+	if gf.objw == nil {
+		if gf.pos != 0 {
+			return 0, errors.New("writing with an offset is not implemented")
+		}
+
+		r, w := io.Pipe()
+		gf.donew = make(chan error, 1)
+		gf.objw = w
+
+		contentType := mime.TypeByExtension(path.Ext(gf.path.key))
+		go func() {
+			_, err := gf.mc.PutObject(context.Background(), gf.path.bucket, gf.path.key, r, -1, minio.PutObjectOptions{ContentType: contentType})
+			gf.donew <- err
+		}()
+	}
+
+	return gf.objw.Write(p)
 }
 
 func (gf *GarageFile) Seek(offset int64, whence int) (int64, error) {
-  if err := gf.loadObject(); err != nil {
-    return 0, err
-  }
-  return gf.obj.Seek(offset, whence)
+	if err := gf.loadObject(); err != nil {
+		return 0, err
+	}
+
+	pos, err := gf.obj.Seek(offset, whence)
+	gf.pos += pos
+	return pos, err
 }
 
 /*
@@ -254,13 +300,14 @@ If n > 0, ReadDir returns at most n DirEntry records. In this case, if ReadDir r
 If n <= 0, ReadDir returns all the DirEntry records remaining in the directory. When it succeeds, it returns a nil error (not io.EOF).
 */
 func (gf *GarageFile) Readdir(count int) ([]fs.FileInfo, error) {
-	log.Println("Call Readdir with count", count)
+	if count > 0 {
+		return nil, errors.New("returning a limited number of directory entry is not supported in readdir")
+	}
 
-	if gf.path == "/" {
+	if gf.path.class == ROOT {
 		return gf.readDirRoot(count)
 	} else {
-		exploded_path := strings.SplitN(gf.path, "/", 3)
-		return gf.readDirChild(count, exploded_path[1], exploded_path[2])
+		return gf.readDirChild(count)
 	}
 }
 
@@ -282,10 +329,9 @@ func (gf *GarageFile) readDirRoot(count int) ([]fs.FileInfo, error) {
 	return entries, nil
 }
 
-func (gf *GarageFile) readDirChild(count int, bucket, prefix string) ([]fs.FileInfo, error) {
-	log.Println("call ListObjects with", bucket, prefix)
-	objs_info := gf.mc.ListObjects(gf.ctx, bucket, minio.ListObjectsOptions{
-		Prefix:    prefix,
+func (gf *GarageFile) readDirChild(count int) ([]fs.FileInfo, error) {
+	objs_info := gf.mc.ListObjects(gf.ctx, gf.path.bucket, minio.ListObjectsOptions{
+		Prefix:    gf.path.key,
 		Recursive: false,
 	})
 
@@ -294,7 +340,7 @@ func (gf *GarageFile) readDirChild(count int, bucket, prefix string) ([]fs.FileI
 		if object.Err != nil {
 			return nil, object.Err
 		}
-		ngf, err := NewGarageStatFromObjectInfo(gf.ctx, bucket, object)
+		ngf, err := NewGarageStatFromObjectInfo(gf.ctx, gf.path.bucket, object)
 		if err != nil {
 			return nil, err
 		}
@@ -305,24 +351,40 @@ func (gf *GarageFile) readDirChild(count int, bucket, prefix string) ([]fs.FileI
 }
 
 func (gf *GarageFile) Stat() (fs.FileInfo, error) {
-	return NewGarageStat(gf.ctx, gf.path)
+	return NewGarageStatFromFile(gf.ctx, gf.path.path)
 }
 
 /* Implements */
 // StatObject???
 type GarageStat struct {
-	obj    minio.ObjectInfo
-	bucket string
+	obj  minio.ObjectInfo
+	ctx  context.Context
+	path S3Path
 }
 
-func NewGarageStat(ctx context.Context, path string) (*GarageStat, error) {
+/*
+ * Stat a path
+ */
+func NewGarageStatFromFile(ctx context.Context, path string) (*GarageStat, error) {
 	cache := ctx.Value(garageEntry).(garageCtx).StatCache
+
+	// Maybe this file is already in our cache?
 	if entry, ok := cache[path]; ok {
 		return entry, nil
 	}
 
-	gs, err := newGarageStatFresh(ctx, path)
-	if err != nil {
+	// Create a placeholder in case we are creating the object
+	gs := new(GarageStat)
+	gs.ctx = ctx
+	gs.path = NewS3Path(path)
+	gs.path.class = OBJECT // known because called from GarageFile
+	gs.obj.Key = gs.path.key
+	gs.obj.LastModified = time.Now()
+
+	// Maybe this file exists in garage?
+	err := gs.Refresh()
+	if err != nil && !os.IsNotExist(err) {
+		// There is an error and this is not a 404, report it.
 		return nil, err
 	}
 
@@ -330,56 +392,92 @@ func NewGarageStat(ctx context.Context, path string) (*GarageStat, error) {
 	return gs, nil
 }
 
-func newGarageStatFresh(ctx context.Context, path string) (*GarageStat, error) {
-	mc := ctx.Value(garageEntry).(garageCtx).MC
+/*
+ * Stat a path knowing its ObjectInfo
+ */
+func NewGarageStatFromObjectInfo(ctx context.Context, bucket string, obj minio.ObjectInfo) (*GarageStat, error) {
 	gs := new(GarageStat)
-	gs.bucket = "/"
-	gs.obj = minio.ObjectInfo{}
+	gs.path = NewTrustedS3Path(bucket, obj)
+	gs.obj = obj
 
-	exploded_path := strings.SplitN(path, "/", 3)
+	cache := ctx.Value(garageEntry).(garageCtx).StatCache
+	cache[gs.path.path] = gs
+	return gs, nil
+}
 
-	// Check if we can extract the bucket name
-	if len(exploded_path) < 2 {
-		return gs, nil
+/*
+ * Stat a path without additional information
+ */
+func NewGarageStat(ctx context.Context, path string) (*GarageStat, error) {
+	log.Println("Probe file", path)
+	cache := ctx.Value(garageEntry).(garageCtx).StatCache
+	if entry, ok := cache[path]; ok {
+		return entry, nil
 	}
-	gs.bucket = exploded_path[1]
 
-	// Check if we can extract the prefix
-	if len(exploded_path) < 3 || exploded_path[2] == "" {
-		return gs, nil
+	gs := new(GarageStat)
+	gs.ctx = ctx
+	gs.path = NewS3Path(path)
+	if err := gs.Refresh(); err != nil {
+		return nil, err
 	}
-	gs.obj.Key = exploded_path[2]
 
-	// Check if this is a file or a folder
-	log.Println("call StatObject with", gs.bucket, gs.obj.Key)
-	obj, err := mc.StatObject(ctx, gs.bucket, gs.obj.Key, minio.StatObjectOptions{})
-	if e, ok := err.(minio.ErrorResponse); ok && e.Code == "NoSuchKey" {
-		return gs, nil
-	}
-	if err != nil {
-		return nil, err
+	if gs.path.class&OPAQUE_KEY != 0 {
+		return nil, errors.New("Failed to precisely determine the key type, this a logic error.")
 	}
 
-	// If it is a file, assign its data
-	gs.obj = obj
+	cache[path] = gs
+	cache[gs.path.path] = gs
 	return gs, nil
 }
 
-func NewGarageStatFromObjectInfo(ctx context.Context, bucket string, obj minio.ObjectInfo) (*GarageStat, error) {
-	gs := new(GarageStat)
-	gs.bucket = bucket
-	gs.obj = obj
+func (gs *GarageStat) Refresh() error {
+	if gs.path.class == ROOT || gs.path.class == BUCKET {
+		return nil
+	}
 
-	cache := ctx.Value(garageEntry).(garageCtx).StatCache
-	cache[path.Join("/", bucket, obj.Key)] = gs
-	return gs, nil
+	mc := gs.ctx.Value(garageEntry).(garageCtx).MC
+
+	// Compute the prefix to have the desired behaviour for our stat logic
+	prefix := gs.path.key
+	if prefix[len(prefix)-1:] == "/" {
+		prefix = prefix[:len(prefix)-1]
+	}
+
+	// Get info and check if the key exists
+	objs_info := mc.ListObjects(gs.ctx, gs.path.bucket, minio.ListObjectsOptions{
+		Prefix:    prefix,
+		Recursive: false,
+	})
+
+	found := false
+	for object := range objs_info {
+		if object.Err != nil {
+			return object.Err
+		}
+
+		if object.Key == prefix || object.Key == prefix+"/" {
+			gs.obj = object
+			gs.path = NewTrustedS3Path(gs.path.bucket, object)
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		return fs.ErrNotExist
+	}
+
+	return nil
 }
 
 func (gs *GarageStat) Name() string {
-	if gs.obj.Key != "" {
-		return path.Base(gs.obj.Key)
+	if gs.path.class == ROOT {
+		return "/"
+	} else if gs.path.class == BUCKET {
+		return gs.path.bucket
 	} else {
-		return gs.bucket
+		return path.Base(gs.path.key)
 	}
 }
 
@@ -388,10 +486,10 @@ func (gs *GarageStat) Size() int64 {
 }
 
 func (gs *GarageStat) Mode() fs.FileMode {
-	if gs.obj.ETag == "" {
-		return fs.ModeDir | fs.ModePerm
-	} else {
+	if gs.path.class == OBJECT {
 		return fs.ModePerm
+	} else {
+		return fs.ModeDir | fs.ModePerm
 	}
 }
 
@@ -400,9 +498,58 @@ func (gs *GarageStat) ModTime() time.Time {
 }
 
 func (gs *GarageStat) IsDir() bool {
-	return gs.Mode().IsDir()
+	return gs.path.class != OBJECT
 }
 
 func (gs *GarageStat) Sys() interface{} {
 	return nil
 }
+
+type S3Class int
+
+const (
+	ROOT S3Class = 1 << iota
+	BUCKET
+	COMMON_PREFIX
+	OBJECT
+	OPAQUE_KEY
+
+	KEY = COMMON_PREFIX | OBJECT | OPAQUE_KEY
+)
+
+type S3Path struct {
+	path   string
+	class  S3Class
+	bucket string
+	key    string
+}
+
+func NewS3Path(path string) S3Path {
+	exploded_path := strings.SplitN(path, "/", 3)
+
+	// If there is no bucket name (eg. "/")
+	if len(exploded_path) < 2 || exploded_path[1] == "" {
+		return S3Path{path, ROOT, "", ""}
+	}
+
+	// If there is no key
+	if len(exploded_path) < 3 || exploded_path[2] == "" {
+		return S3Path{path, BUCKET, exploded_path[1], ""}
+	}
+
+	return S3Path{path, OPAQUE_KEY, exploded_path[1], exploded_path[2]}
+}
+
+func NewTrustedS3Path(bucket string, obj minio.ObjectInfo) S3Path {
+	cl := OBJECT
+	if obj.Key[len(obj.Key)-1:] == "/" {
+		cl = COMMON_PREFIX
+	}
+
+	return S3Path{
+		path:   path.Join("/", bucket, obj.Key),
+		bucket: bucket,
+		key:    obj.Key,
+		class:  cl,
+	}
+}