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use std::io::{BufRead, BufReader, Write}; use std::net::{self, TcpStream}; use std::path::PathBuf; use std::str::from_utf8; use std::time::Duration; use url; 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 { // Because not all platforms uspport 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), } } } /// 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 { 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")), } } } 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() .into_iter() .filter(|&(ref key, _)| key == "db") .next() { Some((_, db)) => unwrap_or!( db.parse::<i64>().ok(), fail!((ErrorKind::InvalidClientConfig, "Invalid database number")) ), None => 0, }, passwd: url.password().and_then(|pw| Some(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: BufReader<TcpStream>, open: bool, } #[cfg(unix)] struct UnixConnection { sock: BufReader<UnixStream>, open: bool, } enum ActualConnection { Tcp(TcpConnection), #[cfg(unix)] Unix(UnixConnection), } /// Represents a stateful redis TCP connection. pub struct Connection { con: ActualConnection, 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. pub struct Msg { payload: Value, channel: Value, pattern: Option<Value>, } impl ActualConnection { pub fn new(addr: &ConnectionAddr) -> RedisResult<ActualConnection> { Ok(match *addr { ConnectionAddr::Tcp(ref host, ref port) => { let host: &str = &*host; let tcp = TcpStream::connect((host, *port))?; let buffered = BufReader::new(tcp); ActualConnection::Tcp(TcpConnection { reader: buffered, open: true, }) } #[cfg(unix)] ConnectionAddr::Unix(ref path) => ActualConnection::Unix(UnixConnection { sock: BufReader::new(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 .get_mut() .write_all(bytes) .map_err(|e| RedisError::from(e)); 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 .get_mut() .write_all(bytes) .map_err(|e| RedisError::from(e)); match result { Err(e) => { if e.is_connection_dropped() { connection.open = false; } Err(e) } Ok(_) => Ok(Value::Okay), } } } } pub fn read_response(&mut self) -> RedisResult<Value> { let result = Parser::new(match *self { ActualConnection::Tcp(TcpConnection { ref mut reader, .. }) => { reader as &mut dyn BufRead } #[cfg(unix)] ActualConnection::Unix(UnixConnection { ref mut sock, .. }) => sock as &mut dyn BufRead, }) .parse_value(); // shutdown connection on protocol error match result { Err(ref e) if e.kind() == ErrorKind::ResponseError => match *self { ActualConnection::Tcp(ref mut connection) => { let _ = connection.reader.get_mut().shutdown(net::Shutdown::Both); connection.open = false; } #[cfg(unix)] ActualConnection::Unix(ref mut connection) => { let _ = connection.sock.get_mut().shutdown(net::Shutdown::Both); connection.open = false; } }, _ => (), } result } pub fn set_write_timeout(&self, dur: Option<Duration>) -> RedisResult<()> { match *self { ActualConnection::Tcp(TcpConnection { ref reader, .. }) => { reader.get_ref().set_write_timeout(dur)?; } #[cfg(unix)] ActualConnection::Unix(UnixConnection { ref sock, .. }) => { sock.get_ref().set_write_timeout(dur)?; } } Ok(()) } pub fn set_read_timeout(&self, dur: Option<Duration>) -> RedisResult<()> { match *self { ActualConnection::Tcp(TcpConnection { ref reader, .. }) => { reader.get_ref().set_read_timeout(dur)?; } #[cfg(unix)] ActualConnection::Unix(UnixConnection { ref sock, .. }) => { sock.get_ref().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) -> RedisResult<Connection> { let con = ActualConnection::new(&connection_info.addr)?; let mut rv = Connection { con: con, db: connection_info.db, pubsub: false, }; match connection_info.passwd { Some(ref passwd) => match cmd("AUTH").arg(&**passwd).query::<Value>(&mut rv) { Ok(Value::Okay) => {} _ => { fail!(( ErrorKind::AuthenticationFailed, "Password authentication failed" )); } }, None => {} } 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; } /// 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.con.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) } pub fn as_pubsub<'a>(&'a mut self) -> PubSub<'a> { // 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().map(|v| *v) { 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(()) } /// 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. pub fn is_open(&self) -> bool { self.con.is_open() } } impl ConnectionLike for Connection { fn req_packed_command(&mut self, cmd: &[u8]) -> RedisResult<Value> { if self.pubsub { self.exit_pubsub()?; } let con = &mut self.con; con.send_bytes(cmd)?; con.read_response() } fn req_packed_commands( &mut self, cmd: &[u8], offset: usize, count: usize, ) -> RedisResult<Vec<Value>> { if self.pubsub { self.exit_pubsub()?; } let con = &mut self.con; con.send_bytes(cmd)?; let mut rv = vec![]; for idx in 0..(offset + count) { let item = con.read_response()?; if idx >= offset { rv.push(item); } } Ok(rv) } fn get_db(&self) -> i64 { self.db } } /// 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<()> { let _: () = cmd("SUBSCRIBE").arg(channel).query(self.con)?; Ok(()) } /// Subscribes to a new channel with a pattern. pub fn psubscribe<T: ToRedisArgs>(&mut self, pchannel: T) -> RedisResult<()> { let _: () = cmd("PSUBSCRIBE").arg(pchannel).query(self.con)?; Ok(()) } /// Unsubscribes from a channel. pub fn unsubscribe<T: ToRedisArgs>(&mut self, channel: T) -> RedisResult<()> { let _: () = cmd("UNSUBSCRIBE").arg(channel).query(self.con)?; Ok(()) } /// Unsubscribes from a channel with a pattern. pub fn punsubscribe<T: ToRedisArgs>(&mut self, pchannel: T) -> RedisResult<()> { let _: () = cmd("PUNSUBSCRIBE").arg(pchannel).query(self.con)?; Ok(()) } /// 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 { let raw_msg: Vec<Value> = from_redis_value(&self.con.recv_response()?)?; let mut iter = raw_msg.into_iter(); let msg_type: String = from_redis_value(&unwrap_or!(iter.next(), continue))?; let mut pattern = None; let payload; let channel; if msg_type == "message" { channel = unwrap_or!(iter.next(), continue); payload = unwrap_or!(iter.next(), continue); } else if msg_type == "pmessage" { pattern = Some(unwrap_or!(iter.next(), continue)); channel = unwrap_or!(iter.next(), continue); payload = unwrap_or!(iter.next(), continue); } else { continue; } return Ok(Msg { payload: payload, channel: channel, pattern: pattern, }); } } /// 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 { /// 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. 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, PipelineCommands}; /// # 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: FromRedisValue, F: FnMut(&mut C, &mut Pipeline) -> RedisResult<Option<T>>, >( con: &mut C, keys: &[K], func: F, ) -> RedisResult<T> { let mut func = func; loop { let _: () = 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. let _: () = cmd("UNWATCH").query(con)?; return Ok(response); } } } }