sketch out an api

file.go

@@ -0,0 +1,112 @@
+package hdfs
+
+import "os"
+
+const clientName = "go-hdfs"
+
+// HdfsFile represents a file or directory in HDFS. It implements the Writer,
+// SectionReader, and Closer interfaces, but not SectionWriter or Seeker.
+type HdfsFile struct {
+	name string
+	closed bool
+}
+
+// Open returns an HdfsFile which can be used for reading.
+func Open(name string) (file *HdfsFile, err error) {
+	return &HdfsFile{name, true}, nil
+}
+
+// Create creates the named file, overwriting it if it already exists.
+// The file can then be used for reading and writing.
+func Create(name string, perm os.FileMode) (file *HdfsFile, err error) {
+	return &HdfsFile{name, true}, nil
+}
+
+// Name returns the name of the file.
+func (f *HdfsFile) Name() string {
+	return f.name
+}
+
+// Read reads up to len(b) bytes from the HdfsFile. It returns the number of bytes
+// read and an error, if any. EOF is signaled by a zero count with err set to
+// io.EOF.
+func (f *HdfsFile) Read(b []byte) (n int, err error) {
+	return 0, nil
+}
+
+// ReadAt reads len(b) bytes from the HdfsFile starting at byte offset off. It
+// returns the number of bytes read and the error, if any. ReadAt always returns
+// a non-nil error when n < len(b). At end of file, that error is io.EOF.
+func (f *HdfsFile) ReadAt(b []byte, off int64) (n int, err error) {
+	return 0, nil
+}
+
+// Readdir reads the contents of the directory associated with file and returns
+// a slice of up to n os.FileInfo values, as would be returned by Stat, in
+// directory order. Subsequent calls on the same file will yield further
+// os.FileInfos.
+//
+// If n > 0, Readdir returns at most n os.FileInfo values. In this case, if
+// Readdir returns an empty slice, it will return a non-nil error explaining
+// why. At the end of a directory, the error is io.EOF.
+//
+// If n <= 0, Readdir returns all the os.FileInfo from the directory in a single
+// slice. In this case, if Readdir succeeds (reads all the way to the end of
+// the directory), it returns the slice and a nil error. If it encounters an
+// error before the end of the directory, Readdir returns the os.FileInfo read
+// until that point and a non-nil error.
+func (f *HdfsFile) Readdir(n int) (fi []os.FileInfo, err error) {
+	return []os.FileInfo{}, nil
+}
+
+// Readdirnames reads and returns a slice of names from the directory f.
+//
+// If n > 0, Readdirnames returns at most n names. In this case, if Readdirnames
+// returns an empty slice, it will return a non-nil error explaining why. At the
+// end of a directory, the error is io.EOF.
+//
+// If n <= 0, Readdirnames returns all the names from the directory in a single
+// slice. In this case, if Readdirnames succeeds (reads all the way to the end
+// of the directory), it returns the slice and a nil error. If it encounters an
+// error before the end of the directory, Readdirnames returns the names read
+// until that point and a non-nil error.
+func (f *HdfsFile) Readdirnames(n int) (names []string, err error) {
+	return []string{}, nil
+}
+
+// Write writes len(b) bytes to the HdfsFile. It returns the number of bytes written
+// and an error, if any. Write returns a non-nil error when n != len(b).
+//
+// Unlike a regular os.File, the contents will be buffered into memory
+func (f *HdfsFile) Write(b []byte) (n int, err error) {
+	return 0, nil
+}
+
+// WriteAt writes len(b) bytes to the HdfsFile starting at byte offset off.
+// It returns the number of bytes written and an error, if any. WriteAt returns
+// a non-nil error when n != len(b).
+func (f *HdfsFile) WriteAt(b []byte, off int64) (n int, err error) {
+	return 0, nil
+}
+
+// WriteString is like Write, but writes the contents of string s rather than a
+// slice of bytes.
+func (f *HdfsFile) WriteString(s string) (ret int, err error) {
+	return 0, nil
+}
+
+// Chmod changes the mode of the file to mode.
+func (f *HdfsFile) Chmod(mode os.FileMode) error {
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+func (f *HdfsFile) Chown(uid, gid int) error {
+	return nil
+}
+
+// Close closes the HdfsFile.
+func (f *HdfsFile) Close() error {
+	return nil
+}
+

hdfs.go

@@ -0,0 +1,80 @@
+package hdfs
+
+import "os"
+
+// Represents a connection to an HDFS Namenode
+type Client struct {
+	namenode string
+}
+
+// New returns a connected Client, or an error if it can't connect
+func New(namenode string) (*Client, error) {
+	return &Client{namenode}, nil
+}
+
+// Chmod changes the mode of the named file to mode.
+func (c *Client) Chmod(name string, mode os.FileMode) error {
+	return nil
+}
+
+// Chown changes the numeric uid and gid of the named file.
+func (c *Client) Chown(name string, uid, gid int) error {
+	return nil
+}
+
+// Mkdir creates a new directory with the specified name and permission bits.
+func (c *Client) Mkdir(name string, perm os.FileMode) error {
+	return nil
+}
+
+// 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.
+func (c *Client) MkdirAll(path string, perm os.FileMode) error {
+	return nil
+}
+
+// Remove removes the named file or directory.
+func (c *Client) Remove(name string) error {
+	return nil
+}
+
+// Rename renames (moves) a file.
+func (c *Client) Rename(oldpath, newpath string) error {
+	return nil
+}
+
+// Stat returns an os.FileInfo describing the named file.
+func (c *Client) Stat(name string) (fi os.FileInfo, err error) {
+	return nil, nil
+}
+
+// ReadDir reads the directory named by dirname and returns a list of sorted
+// directory entries.
+func ReadDir(dirname string) ([]os.FileInfo, error) {
+	return []os.FileInfo{}, nil
+}
+
+// ReadFile reads the file named by filename and returns the contents.
+func ReadFile(filename string) ([]byte, error) {
+	return []byte{}, nil
+}
+
+// WriteFile writes data to a file named by filename. If the file already
+// exists, it will be overwritten
+func WriteFile(filename string, data []byte, perm os.FileMode) error {
+	return nil
+}
+
+// CopyToLocal copies the HDFS file specified by src to the local file at dst.
+// If dst already exists, it will be overwritten.
+func CopyToLocal(src string, dst string, perm os.FileMode) error {
+	return nil
+}
+
+// CopyToHdfs copies the local file at src to a new HDFS file at dst. If it
+// already exists, it will be overwritten.
+func CopyToHdfs(src string, dst string, perm os.FileMode) error {
+	return nil
+}