use std::fmt;
use std::io::Write;
use std::net::{self, TcpStream, ToSocketAddrs};
use std::path::PathBuf;
use std::str::from_utf8;
use std::time::Duration;
use crate::cmd::{cmd, pipe, Pipeline};
use crate::parser::Parser;
use crate::types::{
from_redis_value, ErrorKind, FromRedisValue, RedisError, RedisResult, ToRedisArgs, Value,
};
#[cfg(unix)]
use std::os::unix::net::UnixStream;
static DEFAULT_PORT: u16 = 6379;
/// This function takes a redis URL string and parses it into a URL
/// as used by rust-url. This is necessary as the default parser does
/// not understand how redis URLs function.
pub fn parse_redis_url(input: &str) -> Result<url::Url, ()> {
match url::Url::parse(input) {
Ok(result) => match result.scheme() {
"redis" | "redis+unix" | "unix" => Ok(result),
_ => Err(()),
},
Err(_) => Err(()),
}
}
/// Defines the connection address.
///
/// Not all connection addresses are supported on all platforms. For instance
/// to connect to a unix socket you need to run this on an operating system
/// that supports them.
#[derive(Clone, Debug, PartialEq)]
pub enum ConnectionAddr {
/// Format for this is `(host, port)`.
Tcp(String, u16),
/// Format for this is the path to the unix socket.
Unix(PathBuf),
}
impl ConnectionAddr {
/// Checks if this address is supported.
///
/// Because not all platforms support all connection addresses this is a
/// quick way to figure out if a connection method is supported. Currently
/// this only affects unix connections which are only supported on unix
/// platforms and on older versions of rust also require an explicit feature
/// to be enabled.
pub fn is_supported(&self) -> bool {
match *self {
ConnectionAddr::Tcp(_, _) => true,
ConnectionAddr::Unix(_) => cfg!(unix),
}
}
}
impl fmt::Display for ConnectionAddr {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
ConnectionAddr::Tcp(ref host, port) => write!(f, "{}:{}", host, port),
ConnectionAddr::Unix(ref path) => write!(f, "{}", path.display()),
}
}
}
/// Holds the connection information that redis should use for connecting.
#[derive(Clone, Debug)]
pub struct ConnectionInfo {
/// A boxed connection address for where to connect to.
pub addr: Box<ConnectionAddr>,
/// The database number to use. This is usually `0`.
pub db: i64,
/// Optionally a password that should be used for connection.
pub passwd: Option<String>,
}
/// Converts an object into a connection info struct. This allows the
/// constructor of the client to accept connection information in a
/// range of different formats.
pub trait IntoConnectionInfo {
/// Converts the object into a connection info object.
fn into_connection_info(self) -> RedisResult<ConnectionInfo>;
}
impl IntoConnectionInfo for ConnectionInfo {
fn into_connection_info(self) -> RedisResult<ConnectionInfo> {
Ok(self)
}
}
impl<'a> IntoConnectionInfo for &'a str {
fn into_connection_info(self) -> RedisResult<ConnectionInfo> {
match parse_redis_url(self) {
Ok(u) => u.into_connection_info(),
Err(_) => fail!((ErrorKind::InvalidClientConfig, "Redis URL did not parse")),
}
}
}
impl IntoConnectionInfo for String {
fn into_connection_info(self) -> RedisResult<ConnectionInfo> {
match parse_redis_url(&self) {
Ok(u) => u.into_connection_info(),
Err(_) => fail!((ErrorKind::InvalidClientConfig, "Redis URL did not parse")),
}
}
}
fn url_to_tcp_connection_info(url: url::Url) -> RedisResult<ConnectionInfo> {
Ok(ConnectionInfo {
addr: Box::new(ConnectionAddr::Tcp(
match url.host() {
Some(host) => host.to_string(),
None => fail!((ErrorKind::InvalidClientConfig, "Missing hostname")),
},
url.port().unwrap_or(DEFAULT_PORT),
)),
db: match url.path().trim_matches('/') {
"" => 0,
path => unwrap_or!(
path.parse::<i64>().ok(),
fail!((ErrorKind::InvalidClientConfig, "Invalid database number"))
),
},
passwd: match url.password() {
Some(pw) => match percent_encoding::percent_decode(pw.as_bytes()).decode_utf8() {
Ok(decoded) => Some(decoded.into_owned()),
Err(_) => fail!((
ErrorKind::InvalidClientConfig,
"Password is not valid UTF-8 string"
)),
},
None => None,
},
})
}
#[cfg(unix)]
fn url_to_unix_connection_info(url: url::Url) -> RedisResult<ConnectionInfo> {
Ok(ConnectionInfo {
addr: Box::new(ConnectionAddr::Unix(unwrap_or!(
url.to_file_path().ok(),
fail!((ErrorKind::InvalidClientConfig, "Missing path"))
))),
db: match url.query_pairs().find(|&(ref key, _)| key == "db") {
Some((_, db)) => unwrap_or!(
db.parse::<i64>().ok(),
fail!((ErrorKind::InvalidClientConfig, "Invalid database number"))
),
None => 0,
},
passwd: url.password().map(|pw| pw.to_string()),
})
}
#[cfg(not(unix))]
fn url_to_unix_connection_info(_: url::Url) -> RedisResult<ConnectionInfo> {
fail!((
ErrorKind::InvalidClientConfig,
"Unix sockets are not available on this platform."
));
}
impl IntoConnectionInfo for url::Url {
fn into_connection_info(self) -> RedisResult<ConnectionInfo> {
if self.scheme() == "redis" {
url_to_tcp_connection_info(self)
} else if self.scheme() == "unix" || self.scheme() == "redis+unix" {
url_to_unix_connection_info(self)
} else {
fail!((
ErrorKind::InvalidClientConfig,
"URL provided is not a redis URL"
));
}
}
}
struct TcpConnection {
reader: TcpStream,
open: bool,
}
#[cfg(unix)]
struct UnixConnection {
sock: UnixStream,
open: bool,
}
enum ActualConnection {
Tcp(TcpConnection),
#[cfg(unix)]
Unix(UnixConnection),
}
/// Represents a stateful redis TCP connection.
pub struct Connection {
con: ActualConnection,
parser: Parser,
db: i64,
/// Flag indicating whether the connection was left in the PubSub state after dropping `PubSub`.
///
/// This flag is checked when attempting to send a command, and if it's raised, we attempt to
/// exit the pubsub state before executing the new request.
pubsub: bool,
}
/// Represents a pubsub connection.
pub struct PubSub<'a> {
con: &'a mut Connection,
}
/// Represents a pubsub message.
#[derive(Debug)]
pub struct Msg {
payload: Value,
channel: Value,
pattern: Option<Value>,
}
impl ActualConnection {
pub fn new(addr: &ConnectionAddr, timeout: Option<Duration>) -> RedisResult<ActualConnection> {
Ok(match *addr {
ConnectionAddr::Tcp(ref host, ref port) => {
let host: &str = &*host;
let tcp = match timeout {
None => TcpStream::connect((host, *port))?,
Some(timeout) => {
let mut tcp = None;
let mut last_error = None;
for addr in (host, *port).to_socket_addrs()? {
match TcpStream::connect_timeout(&addr, timeout) {
Ok(l) => {
tcp = Some(l);
break;
}
Err(e) => {
last_error = Some(e);
}
};
}
match (tcp, last_error) {
(Some(tcp), _) => tcp,
(None, Some(e)) => {
fail!(e);
}
(None, None) => {
fail!((
ErrorKind::InvalidClientConfig,
"could not resolve to any addresses"
));
}
}
}
};
ActualConnection::Tcp(TcpConnection {
reader: tcp,
open: true,
})
}
#[cfg(unix)]
ConnectionAddr::Unix(ref path) => ActualConnection::Unix(UnixConnection {
sock: UnixStream::connect(path)?,
open: true,
}),
#[cfg(not(unix))]
ConnectionAddr::Unix(ref _path) => {
fail!((
ErrorKind::InvalidClientConfig,
"Cannot connect to unix sockets \
on this platform"
));
}
})
}
pub fn send_bytes(&mut self, bytes: &[u8]) -> RedisResult<Value> {
match *self {
ActualConnection::Tcp(ref mut connection) => {
let res = connection.reader.write_all(bytes).map_err(RedisError::from);
match res {
Err(e) => {
if e.is_connection_dropped() {
connection.open = false;
}
Err(e)
}
Ok(_) => Ok(Value::Okay),
}
}
#[cfg(unix)]
ActualConnection::Unix(ref mut connection) => {
let result = connection.sock.write_all(bytes).map_err(RedisError::from);
match result {
Err(e) => {
if e.is_connection_dropped() {
connection.open = false;
}
Err(e)
}
Ok(_) => Ok(Value::Okay),
}
}
}
}
pub fn set_write_timeout(&self, dur: Option<Duration>) -> RedisResult<()> {
match *self {
ActualConnection::Tcp(TcpConnection { ref reader, .. }) => {
reader.set_write_timeout(dur)?;
}
#[cfg(unix)]
ActualConnection::Unix(UnixConnection { ref sock, .. }) => {
sock.set_write_timeout(dur)?;
}
}
Ok(())
}
pub fn set_read_timeout(&self, dur: Option<Duration>) -> RedisResult<()> {
match *self {
ActualConnection::Tcp(TcpConnection { ref reader, .. }) => {
reader.set_read_timeout(dur)?;
}
#[cfg(unix)]
ActualConnection::Unix(UnixConnection { ref sock, .. }) => {
sock.set_read_timeout(dur)?;
}
}
Ok(())
}
pub fn is_open(&self) -> bool {
match *self {
ActualConnection::Tcp(TcpConnection { open, .. }) => open,
#[cfg(unix)]
ActualConnection::Unix(UnixConnection { open, .. }) => open,
}
}
}
pub fn connect(
connection_info: &ConnectionInfo,
timeout: Option<Duration>,
) -> RedisResult<Connection> {
let con = ActualConnection::new(&connection_info.addr, timeout)?;
let mut rv = Connection {
con,
parser: Parser::new(),
db: connection_info.db,
pubsub: false,
};
if let Some(ref passwd) = connection_info.passwd {
match cmd("AUTH").arg(&**passwd).query::<Value>(&mut rv) {
Ok(Value::Okay) => {}
_ => {
fail!((
ErrorKind::AuthenticationFailed,
"Password authentication failed"
));
}
}
}
if connection_info.db != 0 {
match cmd("SELECT")
.arg(connection_info.db)
.query::<Value>(&mut rv)
{
Ok(Value::Okay) => {}
_ => fail!((
ErrorKind::ResponseError,
"Redis server refused to switch database"
)),
}
}
Ok(rv)
}
/// Implements the "stateless" part of the connection interface that is used by the
/// different objects in redis-rs. Primarily it obviously applies to `Connection`
/// object but also some other objects implement the interface (for instance
/// whole clients or certain redis results).
///
/// Generally clients and connections (as well as redis results of those) implement
/// this trait. Actual connections provide more functionality which can be used
/// to implement things like `PubSub` but they also can modify the intrinsic
/// state of the TCP connection. This is not possible with `ConnectionLike`
/// implementors because that functionality is not exposed.
pub trait ConnectionLike {
/// Sends an already encoded (packed) command into the TCP socket and
/// reads the single response from it.
fn req_packed_command(&mut self, cmd: &[u8]) -> RedisResult<Value>;
/// Sends multiple already encoded (packed) command into the TCP socket
/// and reads `count` responses from it. This is used to implement
/// pipelining.
fn req_packed_commands(
&mut self,
cmd: &[u8],
offset: usize,
count: usize,
) -> RedisResult<Vec<Value>>;
/// Returns the database this connection is bound to. Note that this
/// information might be unreliable because it's initially cached and
/// also might be incorrect if the connection like object is not
/// actually connected.
fn get_db(&self) -> i64;
/// Does this connection support pipelining?
#[doc(hidden)]
fn supports_pipelining(&self) -> bool {
true
}
/// Check that all connections it has are available (`PING` internally).
fn check_connection(&mut self) -> bool;
/// Returns the connection status.
///
/// The connection is open until any `read_response` call recieved an
/// invalid response from the server (most likely a closed or dropped
/// connection, otherwise a Redis protocol error). When using unix
/// sockets the connection is open until writing a command failed with a
/// `BrokenPipe` error.
fn is_open(&self) -> bool;
}
/// A connection is an object that represents a single redis connection. It
/// provides basic support for sending encoded commands into a redis connection
/// and to read a response from it. It's bound to a single database and can
/// only be created from the client.
///
/// You generally do not much with this object other than passing it to
/// `Cmd` objects.
impl Connection {
/// Sends an already encoded (packed) command into the TCP socket and
/// does not read a response. This is useful for commands like
/// `MONITOR` which yield multiple items. This needs to be used with
/// care because it changes the state of the connection.
pub fn send_packed_command(&mut self, cmd: &[u8]) -> RedisResult<()> {
self.con.send_bytes(cmd)?;
Ok(())
}
/// Fetches a single response from the connection. This is useful
/// if used in combination with `send_packed_command`.
pub fn recv_response(&mut self) -> RedisResult<Value> {
self.read_response()
}
/// Sets the write timeout for the connection.
///
/// If the provided value is `None`, then `send_packed_command` call will
/// block indefinitely. It is an error to pass the zero `Duration` to this
/// method.
pub fn set_write_timeout(&self, dur: Option<Duration>) -> RedisResult<()> {
self.con.set_write_timeout(dur)
}
/// Sets the read timeout for the connection.
///
/// If the provided value is `None`, then `recv_response` call will
/// block indefinitely. It is an error to pass the zero `Duration` to this
/// method.
pub fn set_read_timeout(&self, dur: Option<Duration>) -> RedisResult<()> {
self.con.set_read_timeout(dur)
}
/// Creates a [`PubSub`] instance for this connection.
pub fn as_pubsub(&mut self) -> PubSub<'_> {
// NOTE: The pubsub flag is intentionally not raised at this time since
// running commands within the pubsub state should not try and exit from
// the pubsub state.
PubSub::new(self)
}
fn exit_pubsub(&mut self) -> RedisResult<()> {
let res = self.clear_active_subscriptions();
if res.is_ok() {
self.pubsub = false;
} else {
// Raise the pubsub flag to indicate the connection is "stuck" in that state.
self.pubsub = true;
}
res
}
/// Get the inner connection out of a PubSub
///
/// Any active subscriptions are unsubscribed. In the event of an error, the connection is
/// dropped.
fn clear_active_subscriptions(&mut self) -> RedisResult<()> {
// Responses to unsubscribe commands return in a 3-tuple with values
// ("unsubscribe" or "punsubscribe", name of subscription removed, count of remaining subs).
// The "count of remaining subs" includes both pattern subscriptions and non pattern
// subscriptions. Thus, to accurately drain all unsubscribe messages received from the
// server, both commands need to be executed at once.
{
// Prepare both unsubscribe commands
let unsubscribe = cmd("UNSUBSCRIBE").get_packed_command();
let punsubscribe = cmd("PUNSUBSCRIBE").get_packed_command();
// Grab a reference to the underlying connection so that we may send
// the commands without immediately blocking for a response.
let con = &mut self.con;
// Execute commands
con.send_bytes(&unsubscribe)?;
con.send_bytes(&punsubscribe)?;
}
// Receive responses
//
// There will be at minimum two responses - 1 for each of punsubscribe and unsubscribe
// commands. There may be more responses if there are active subscriptions. In this case,
// messages are received until the _subscription count_ in the responses reach zero.
let mut received_unsub = false;
let mut received_punsub = false;
loop {
let res: (Vec<u8>, (), isize) = from_redis_value(&self.recv_response()?)?;
match res.0.first() {
Some(&b'u') => received_unsub = true,
Some(&b'p') => received_punsub = true,
_ => (),
}
if received_unsub && received_punsub && res.2 == 0 {
break;
}
}
// Finally, the connection is back in its normal state since all subscriptions were
// cancelled *and* all unsubscribe messages were received.
Ok(())
}
/// Fetches a single response from the connection.
fn read_response(&mut self) -> RedisResult<Value> {
let result = match self.con {
ActualConnection::Tcp(TcpConnection { ref mut reader, .. }) => {
self.parser.parse_value(reader)
}
#[cfg(unix)]
ActualConnection::Unix(UnixConnection { ref mut sock, .. }) => {
self.parser.parse_value(sock)
}
};
// shutdown connection on protocol error
match result {
Err(ref e) if e.kind() == ErrorKind::ResponseError => match self.con {
ActualConnection::Tcp(ref mut connection) => {
let _ = connection.reader.shutdown(net::Shutdown::Both);
connection.open = false;
}
#[cfg(unix)]
ActualConnection::Unix(ref mut connection) => {
let _ = connection.sock.shutdown(net::Shutdown::Both);
connection.open = false;
}
},
_ => (),
}
result
}
}
impl ConnectionLike for Connection {
fn req_packed_command(&mut self, cmd: &[u8]) -> RedisResult<Value> {
if self.pubsub {
self.exit_pubsub()?;
}
self.con.send_bytes(cmd)?;
self.read_response()
}
fn req_packed_commands(
&mut self,
cmd: &[u8],
offset: usize,
count: usize,
) -> RedisResult<Vec<Value>> {
if self.pubsub {
self.exit_pubsub()?;
}
self.con.send_bytes(cmd)?;
let mut rv = vec![];
for idx in 0..(offset + count) {
let item = self.read_response()?;
if idx >= offset {
rv.push(item);
}
}
Ok(rv)
}
fn get_db(&self) -> i64 {
self.db
}
fn is_open(&self) -> bool {
self.con.is_open()
}
fn check_connection(&mut self) -> bool {
cmd("PING").query::<String>(self).is_ok()
}
}
/// The pubsub object provides convenient access to the redis pubsub
/// system. Once created you can subscribe and unsubscribe from channels
/// and listen in on messages.
///
/// Example:
///
/// ```rust,no_run
/// # fn do_something() -> redis::RedisResult<()> {
/// let client = redis::Client::open("redis://127.0.0.1/")?;
/// let mut con = client.get_connection()?;
/// let mut pubsub = con.as_pubsub();
/// pubsub.subscribe("channel_1")?;
/// pubsub.subscribe("channel_2")?;
///
/// loop {
/// let msg = pubsub.get_message()?;
/// let payload : String = msg.get_payload()?;
/// println!("channel '{}': {}", msg.get_channel_name(), payload);
/// }
/// # }
/// ```
impl<'a> PubSub<'a> {
fn new(con: &'a mut Connection) -> Self {
Self { con }
}
/// Subscribes to a new channel.
pub fn subscribe<T: ToRedisArgs>(&mut self, channel: T) -> RedisResult<()> {
Ok(cmd("SUBSCRIBE").arg(channel).query(self.con)?)
}
/// Subscribes to a new channel with a pattern.
pub fn psubscribe<T: ToRedisArgs>(&mut self, pchannel: T) -> RedisResult<()> {
Ok(cmd("PSUBSCRIBE").arg(pchannel).query(self.con)?)
}
/// Unsubscribes from a channel.
pub fn unsubscribe<T: ToRedisArgs>(&mut self, channel: T) -> RedisResult<()> {
Ok(cmd("UNSUBSCRIBE").arg(channel).query(self.con)?)
}
/// Unsubscribes from a channel with a pattern.
pub fn punsubscribe<T: ToRedisArgs>(&mut self, pchannel: T) -> RedisResult<()> {
Ok(cmd("PUNSUBSCRIBE").arg(pchannel).query(self.con)?)
}
/// Fetches the next message from the pubsub connection. Blocks until
/// a message becomes available. This currently does not provide a
/// wait not to block :(
///
/// The message itself is still generic and can be converted into an
/// appropriate type through the helper methods on it.
pub fn get_message(&mut self) -> RedisResult<Msg> {
loop {
if let Some(msg) = Msg::from_value(&self.con.recv_response()?) {
return Ok(msg);
} else {
continue;
}
}
}
/// Sets the read timeout for the connection.
///
/// If the provided value is `None`, then `get_message` call will
/// block indefinitely. It is an error to pass the zero `Duration` to this
/// method.
pub fn set_read_timeout(&self, dur: Option<Duration>) -> RedisResult<()> {
self.con.set_read_timeout(dur)
}
}
impl<'a> Drop for PubSub<'a> {
fn drop(&mut self) {
let _ = self.con.exit_pubsub();
}
}
/// This holds the data that comes from listening to a pubsub
/// connection. It only contains actual message data.
impl Msg {
/// Tries to convert provided [`Value`] into [`Msg`].
pub fn from_value(value: &Value) -> Option<Self> {
let raw_msg: Vec<Value> = from_redis_value(value).ok()?;
let mut iter = raw_msg.into_iter();
let msg_type: String = from_redis_value(&iter.next()?).ok()?;
let mut pattern = None;
let payload;
let channel;
if msg_type == "message" {
channel = iter.next()?;
payload = iter.next()?;
} else if msg_type == "pmessage" {
pattern = Some(iter.next()?);
channel = iter.next()?;
payload = iter.next()?;
} else {
return None;
}
Some(Msg {
payload,
channel,
pattern,
})
}
/// Returns the channel this message came on.
pub fn get_channel<T: FromRedisValue>(&self) -> RedisResult<T> {
from_redis_value(&self.channel)
}
/// Convenience method to get a string version of the channel. Unless
/// your channel contains non utf-8 bytes you can always use this
/// method. If the channel is not a valid string (which really should
/// not happen) then the return value is `"?"`.
pub fn get_channel_name(&self) -> &str {
match self.channel {
Value::Data(ref bytes) => from_utf8(bytes).unwrap_or("?"),
_ => "?",
}
}
/// Returns the message's payload in a specific format.
pub fn get_payload<T: FromRedisValue>(&self) -> RedisResult<T> {
from_redis_value(&self.payload)
}
/// Returns the bytes that are the message's payload. This can be used
/// as an alternative to the `get_payload` function if you are interested
/// in the raw bytes in it.
pub fn get_payload_bytes(&self) -> &[u8] {
match self.payload {
Value::Data(ref bytes) => bytes,
_ => b"",
}
}
/// Returns true if the message was constructed from a pattern
/// subscription.
#[allow(clippy::wrong_self_convention)]
pub fn from_pattern(&self) -> bool {
self.pattern.is_some()
}
/// If the message was constructed from a message pattern this can be
/// used to find out which one. It's recommended to match against
/// an `Option<String>` so that you do not need to use `from_pattern`
/// to figure out if a pattern was set.
pub fn get_pattern<T: FromRedisValue>(&self) -> RedisResult<T> {
match self.pattern {
None => from_redis_value(&Value::Nil),
Some(ref x) => from_redis_value(x),
}
}
}
/// This function simplifies transaction management slightly. What it
/// does is automatically watching keys and then going into a transaction
/// loop util it succeeds. Once it goes through the results are
/// returned.
///
/// To use the transaction two pieces of information are needed: a list
/// of all the keys that need to be watched for modifications and a
/// closure with the code that should be execute in the context of the
/// transaction. The closure is invoked with a fresh pipeline in atomic
/// mode. To use the transaction the function needs to return the result
/// from querying the pipeline with the connection.
///
/// The end result of the transaction is then available as the return
/// value from the function call.
///
/// Example:
///
/// ```rust,no_run
/// use redis::Commands;
/// # fn do_something() -> redis::RedisResult<()> {
/// # let client = redis::Client::open("redis://127.0.0.1/").unwrap();
/// # let mut con = client.get_connection().unwrap();
/// let key = "the_key";
/// let (new_val,) : (isize,) = redis::transaction(&mut con, &[key], |con, pipe| {
/// let old_val : isize = con.get(key)?;
/// pipe
/// .set(key, old_val + 1).ignore()
/// .get(key).query(con)
/// })?;
/// println!("The incremented number is: {}", new_val);
/// # Ok(()) }
/// ```
pub fn transaction<
C: ConnectionLike,
K: ToRedisArgs,
T,
F: FnMut(&mut C, &mut Pipeline) -> RedisResult<Option<T>>,
>(
con: &mut C,
keys: &[K],
func: F,
) -> RedisResult<T> {
let mut func = func;
loop {
cmd("WATCH").arg(keys).query::<()>(con)?;
let mut p = pipe();
let response: Option<T> = func(con, p.atomic())?;
match response {
None => {
continue;
}
Some(response) => {
// make sure no watch is left in the connection, even if
// someone forgot to use the pipeline.
cmd("UNWATCH").query::<()>(con)?;
return Ok(response);
}
}
}
}