1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162

use futures::{try_ready, Async, Future, Poll};
use redis::aio::{Connection, ConnectionLike};
use redis::{IntoConnectionInfo, RedisError, RedisFuture, RedisResult};
pub use tokio_resource_pool::{Builder, CheckOutFuture};
use tokio_resource_pool::{CheckOut, Manage, Pool, RealDependencies, Status};

/// Manages the lifecycle of connections to a single Redis server.
pub struct RedisManager {
    client: redis::Client,
}

impl RedisManager {
    /// Creates a new `RedisManager` from anything that can be converted to a `ConnectionInfo`.
    ///
    /// # Example
    ///
    /// ```
    /// # use tokio_redis_pool::RedisManager;
    /// # use redis::RedisResult;
    /// # fn main() -> RedisResult<()> {
    /// let manager = RedisManager::new("redis://127.0.0.1:6379")?;
    /// # Ok(())
    /// # }
    /// ```
    pub fn new(params: impl IntoConnectionInfo) -> RedisResult<Self> {
        let client = redis::Client::open(params)?;
        Ok(Self { client })
    }
}

impl Manage for RedisManager {
    type Resource = Connection;

    type Dependencies = RealDependencies;

    type CheckOut = RedisCheckOut;

    type Error = RedisError;

    type CreateFuture = Box<dyn Future<Item = Self::Resource, Error = Self::Error> + Send>;

    fn create(&self) -> Self::CreateFuture {
        Box::new(self.client.get_async_connection())
    }

    fn status(&self, _: &Self::Resource) -> Status {
        Status::Valid
    }

    type RecycleFuture = RecycleFuture;

    fn recycle(&self, connection: Self::Resource) -> Self::RecycleFuture {
        let inner = redis::cmd("PING").query_async::<_, ()>(connection);
        RecycleFuture { inner }
    }
}

/// A resource `Pool` specialized for Redis connections.
pub type RedisPool = Pool<RedisManager>;

/// A check out of a Redis connection from the pool.
///
/// It implements `ConnectionLike`, so you can pass it directly to functions such as
/// `Pipeline::query`.
///
/// # Example
///
/// ```
/// # use futures::future::Future;
/// # use redis::RedisResult;
/// # use tokio_redis_pool::{Builder, RedisManager, RedisPool};
/// # let manager = RedisManager::new("redis://127.0.0.1:6379").unwrap();
/// # let pool = Builder::new().build(4, manager);
/// tokio::run(
///     pool
///         .check_out()
///         .and_then(|connection| redis::cmd("INFO").query_async::<_, redis::InfoDict>(connection))
///         .map(|(_checked_out_connection, info)| println!("{:#?}", info))
///         .map_err(|error| eprintln!("{}", error)),
/// );
/// ```
pub struct RedisCheckOut {
    inner: CheckOut<RedisManager>,
}

impl ConnectionLike for RedisCheckOut {
    fn req_packed_command(
        self,
        cmd: Vec<u8>,
    ) -> Box<dyn Future<Item = (Self, redis::Value), Error = RedisError> + Send> {
        let borrower = move |connection: Connection| connection.req_packed_command(cmd);
        Box::new(self.inner.lend(borrower))
    }

    fn req_packed_commands(
        self,
        cmd: Vec<u8>,
        offset: usize,
        count: usize,
    ) -> Box<dyn Future<Item = (Self, Vec<redis::Value>), Error = RedisError> + Send> {
        let borrower =
            move |connection: Connection| connection.req_packed_commands(cmd, offset, count);
        Box::new(self.inner.lend(borrower))
    }

    fn get_db(&self) -> i64 {
        self.inner.get_db()
    }
}

impl From<CheckOut<RedisManager>> for RedisCheckOut {
    fn from(inner: CheckOut<RedisManager>) -> Self {
        Self { inner }
    }
}

pub struct RecycleFuture {
    inner: RedisFuture<(Connection, ())>,
}

impl Future for RecycleFuture {
    type Item = Option<Connection>;

    type Error = RedisError;

    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
        let (connection, ()) = try_ready!(self.inner.poll());
        Ok(Async::Ready(Some(connection)))
    }
}

#[cfg(test)]
mod tests {
    use super::{Builder, RedisManager};
    use futures::future::Future;

    #[test]
    fn checkout_and_read() {
        let redis_url = "redis://127.0.0.1/";
        {
            let mut client = redis::Client::open(redis_url).unwrap();
            redis::cmd("HSET")
                .arg("greetings")
                .arg("english")
                .arg("hello")
                .execute(&mut client);
        }

        let manager = RedisManager::new(redis_url).unwrap();
        let pool = Builder::new().build(4, manager);
        let mut runtime = tokio::runtime::Runtime::new().unwrap();

        let result = runtime.block_on(pool.check_out().and_then(|connection| {
            redis::cmd("HGET")
                .arg("greetings")
                .arg("english")
                .query_async::<_, String>(connection)
                .map(|(_, v)| v)
        }));
        assert_eq!(Ok("hello".to_string()), result);
    }
}