small refactor*

server/pkg/go-nfs/filesystem.go

@@ -0,0 +1,97 @@
+package nfs
+
+import (
+	"context"
+	"io"
+	"os"
+	"time"
+
+	"github.com/royalcat/ctxio"
+)
+
+// FSStat returns metadata about a file system
+type FSStat struct {
+	TotalSize      uint64
+	FreeSize       uint64
+	AvailableSize  uint64
+	TotalFiles     uint64
+	FreeFiles      uint64
+	AvailableFiles uint64
+	// CacheHint is called "invarsec" in the nfs standard
+	CacheHint time.Duration
+}
+
+type Filesystem interface {
+	// Create creates the named file with mode 0666 (before umask), truncating
+	// it if it already exists. If successful, methods on the returned File can
+	// be used for I/O; the associated file descriptor has mode O_RDWR.
+	Create(ctx context.Context, filename string) (File, error)
+	// OpenFile is the generalized open call; most users will use Open or Create
+	// instead. It opens the named file with specified flag (O_RDONLY etc.) and
+	// perm, (0666 etc.) if applicable. If successful, methods on the returned
+	// File can be used for I/O.
+	OpenFile(ctx context.Context, filename string, flag int, perm os.FileMode) (File, error)
+	// Stat returns a FileInfo describing the named file.
+	Stat(ctx context.Context, filename string) (os.FileInfo, error)
+	// Rename renames (moves) oldpath to newpath. If newpath already exists and
+	// is not a directory, Rename replaces it. OS-specific restrictions may
+	// apply when oldpath and newpath are in different directories.
+	Rename(ctx context.Context, oldpath, newpath string) error
+	// Remove removes the named file or directory.
+	Remove(ctx context.Context, filename string) error
+	// Join joins any number of path elements into a single path, adding a
+	// Separator if necessary. Join calls filepath.Clean on the result; in
+	// particular, all empty strings are ignored. On Windows, the result is a
+	// UNC path if and only if the first path element is a UNC path.
+	Join(elem ...string) string
+
+	// ReadDir reads the directory named by d(irname and returns a list of
+	// directory entries sorted by filename.
+	ReadDir(ctx context.Context, path string) ([]os.FileInfo, error)
+	// MkdirAll creates a directory named path, along with any necessary
+	// parents, and returns nil, or else returns an error. The permission bits
+	// perm are used for all directories that MkdirAll creates. If path is/
+	// already a directory, MkdirAll does nothing and returns nil.
+	MkdirAll(ctx context.Context, filename string, perm os.FileMode) error
+
+	// Lstat returns a FileInfo describing the named file. If the file is a
+	// symbolic link, the returned FileInfo describes the symbolic link. Lstat
+	// makes no attempt to follow the link.
+	Lstat(ctx context.Context, filename string) (os.FileInfo, error)
+	// Symlink creates a symbolic-link from link to target. target may be an
+	// absolute or relative path, and need not refer to an existing node.
+	// Parent directories of link are created as necessary.
+	Symlink(ctx context.Context, target, link string) error
+	// Readlink returns the target path of link.
+	Readlink(ctx context.Context, link string) (string, error)
+}
+
+type File interface {
+	// Name returns the name of the file as presented to Open.
+	Name() string
+	ctxio.Writer
+	// ctxio.Reader
+	ctxio.ReaderAt
+	io.Seeker
+	ctxio.Closer
+
+	// Truncate the file.
+	Truncate(ctx context.Context, size int64) error
+}
+
+// Change abstract the FileInfo change related operations in a storage-agnostic
+// interface as an extension to the Basic interface
+type Change interface {
+	// Chmod changes the mode of the named file to mode. If the file is a
+	// symbolic link, it changes the mode of the link's target.
+	Chmod(ctx context.Context, name string, mode os.FileMode) error
+	// Lchown changes the numeric uid and gid of the named file. If the file is
+	// a symbolic link, it changes the uid and gid of the link itself.
+	Lchown(ctx context.Context, name string, uid, gid int) error
+	// Chtimes changes the access and modification times of the named file,
+	// similar to the Unix utime() or utimes() functions.
+	//
+	// The underlying filesystem may truncate or round the values to a less
+	// precise time unit.
+	Chtimes(ctx context.Context, name string, atime time.Time, mtime time.Time) error
+}