Struct hdrs::Client

pub struct Client { /* private fields */ }

Client holds the underlying connection to hdfs clusters.

The connection will be disconnected while Drop, so their is no need to terminate it manually.

Note

Hadoop will have it’s own filesystem logic which may return the same filesystem instance while hdfsConnect. If we call hdfsDisconnect, all clients that hold this filesystem instance will meet java.io.IOException: Filesystem closed during I/O operations.

So it’s better for us to not call hdfsDisconnect manually. Aka, don’t implement Drop to disconnect the connection.

Reference: IOException: Filesystem closed exception when running oozie workflo

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .with_kerberos_ticket_cache_path("/tmp/krb5_111")
    .connect();

Implementations

impl Client

pub fn open_file(&self) -> OpenOptions

Open will create a stream builder for later IO operations.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let open_options = fs.open_file();

pub fn remove_file(&self, path: &str) -> Result<()>

Delete a file.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let _ = fs.remove_file("/tmp/hello.txt");

pub fn rename_file(&self, old_path: &str, new_path: &str) -> Result<()>

Rename a file.

ATTENTION: the destination directory must exist.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let _ = fs.rename_file("/tmp/hello.txt._COPY_", "/tmp/hello.txt");

pub fn remove_dir(&self, path: &str) -> Result<()>

Delete a dir.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let _ = fs.remove_dir("/tmp/xxx");

pub fn remove_dir_all(&self, path: &str) -> Result<()>

Delete a dir recursively.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let _ = fs.remove_dir_all("/tmp/xxx/");

pub fn metadata(&self, path: &str) -> Result<Metadata>

Stat a path to get file info.

Examples

Stat a path to file info

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let fi = fs.metadata("/tmp/hello.txt");

Stat a non-exist path

use std::io;

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let fi = fs.metadata("/tmp/not-exist.txt");
assert!(fi.is_err());
assert_eq!(fi.unwrap_err().kind(), io::ErrorKind::NotFound)

pub fn read_dir(&self, path: &str) -> Result<Readdir>

readdir will read file entries from a file.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let fis = fs.read_dir("/tmp/hello/");

pub fn create_dir(&self, path: &str) -> Result<()>

mkdir create dir and all it’s parent directories.

The behavior is similar to mkdir -p /path/to/dir.

Examples

use hdrs::{Client, ClientBuilder};

let fs = ClientBuilder::new("default")
    .with_user("default")
    .connect()
    .expect("client connect succeed");
let _ = fs.create_dir("/tmp");

Trait Implementations

impl Debug for Client

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Send for Client

HDFS’s client handle is thread safe.

impl Sync for Client