connpool

README

Server Example

Client Dial using connections pool Example

这个是什么

这个是一个客户端的连接池。其原理就是建立一个简单的线程安全队列，提前建立好MIN_SIZE（默认128个）个连接，当调用Read()或者Write()函数的时候，会从队列中取一个，然后写入或者读取，然后再放回队列中，方便下一次复用。只有当你调用Close()函数，建立的连接才能被安全的关闭。

为什么要这么设计

1.允许在不同goroutine中对TCP连接进行Read，Write。也就是说，你不必再拘束于一个TCP连接，你可以同时写入多个或者读取多个，而且这是线程安全的。（为什么？因为每个连接都是独立的，互不影响）

2.上述并发读写很美妙，但是会出现一个问题，当goroutine太多，超过系统HARD LIMIT/SOFT LIMIT时候，触发Too many open files等错误，为解决此问题，连接池会限制最大连接数，当池子中已经没有可用连接，会等候连接入队进行重利用，当超过TIMEOUT时间后，仍没有入队连接，会尝试建立连接。

Documentation

Index

• Constants
• func GetSysMax() int32
• func Wrapper(p *Pool) net.Conn
• type Conn
  • func (cn *Conn) Close() error
  • func (cn *Conn) LocalAddr() net.Addr
  • func (cn *Conn) Read(b []byte) (n int, err error)
  • func (cn *Conn) RemoteAddr() net.Addr
  • func (cn *Conn) SetDeadline(t time.Time) error
  • func (cn *Conn) SetReadDeadline(t time.Time) error
  • func (cn *Conn) SetWriteDeadline(t time.Time) error
  • func (cn *Conn) Write(b []byte) (n int, err error)
• type Opts
  • func DefaultOpts() Opts
  • func (o Opts) Parse() (*net.Dialer, time.Duration, int32, context.Context)
  • func (o Opts) WithContext(c context.Context)
  • func (o Opts) WithDialer(d *net.Dialer)
  • func (o Opts) WithMinSize(m int32)
  • func (o Opts) WithTimeout(t time.Duration)
• type Pool
  • func New(remoteAddr string, opts Opts) *Pool
  • func (p *Pool) Close()
  • func (p *Pool) Flush()
  • func (p *Pool) Get() (net.Conn, error)
  • func (p *Pool) Len() int32
  • func (p *Pool) Put(c net.Conn)
  • func (p *Pool) SetDeadline(t time.Time)
  • func (p *Pool) SetReadDeadline(t time.Time)
  • func (p *Pool) SetWriteDeadline(t time.Time)

Constants

const (
	MIN_SIZE = 128
)

Functions

func GetSysMax

func GetSysMax() int32

func Wrapper

func Wrapper(p *Pool) net.Conn

Types

type Conn

type Conn struct {
	// contains filtered or unexported fields
}

func (*Conn) Close

func (cn *Conn) Close() error

func (*Conn) LocalAddr

func (cn *Conn) LocalAddr() net.Addr

func (*Conn) Read

func (cn *Conn) Read(b []byte) (n int, err error)

func (*Conn) RemoteAddr

func (cn *Conn) RemoteAddr() net.Addr

func (*Conn) SetDeadline

func (cn *Conn) SetDeadline(t time.Time) error

func (*Conn) SetReadDeadline

func (cn *Conn) SetReadDeadline(t time.Time) error

func (*Conn) SetWriteDeadline

func (cn *Conn) SetWriteDeadline(t time.Time) error

func (*Conn) Write

func (cn *Conn) Write(b []byte) (n int, err error)

type Opts

type Opts []interface{}

func DefaultOpts

func DefaultOpts() Opts

func (Opts) Parse

func (o Opts) Parse() (*net.Dialer, time.Duration, int32, context.Context)

func (Opts) WithContext

func (o Opts) WithContext(c context.Context)

func (Opts) WithDialer

func (o Opts) WithDialer(d *net.Dialer)

func (Opts) WithMinSize

func (o Opts) WithMinSize(m int32)

func (Opts) WithTimeout

func (o Opts) WithTimeout(t time.Duration)

type Pool

type Pool struct {
	Deadline struct {
		// contains filtered or unexported fields
	}
	// contains filtered or unexported fields
}

func New

func New(remoteAddr string, opts Opts) *Pool

func (*Pool) Close

func (p *Pool) Close()

func (*Pool) Flush

func (p *Pool) Flush()

Flush dequeues all TCP Connections and close them.

func (*Pool) Get

func (p *Pool) Get() (net.Conn, error)

Get one TCP connection from the pool.

If the connection reaches the max limit, poll until one enqueue during TIMEOUT.

If not, set up a new one

func (*Pool) Len

func (p *Pool) Len() int32

func (*Pool) Put

func (p *Pool) Put(c net.Conn)

Put the TCP connection into the pool.

func (*Pool) SetDeadline

func (p *Pool) SetDeadline(t time.Time)

func (*Pool) SetReadDeadline

func (p *Pool) SetReadDeadline(t time.Time)

func (*Pool) SetWriteDeadline

func (p *Pool) SetWriteDeadline(t time.Time)