Move connection pool to own package

client/pool/default.go

@@ -0,0 +1,114 @@
+package pool
+
+import (
+	"sync"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/micro/go-micro/transport"
+)
+
+type pool struct {
+	size int
+	ttl  time.Duration
+	tr   transport.Transport
+
+	sync.Mutex
+	conns map[string][]*poolConn
+}
+
+type poolConn struct {
+	transport.Client
+	id      string
+	created time.Time
+}
+
+func newPool(options Options) *pool {
+	return &pool{
+		size:  options.Size,
+		tr:    options.Transport,
+		ttl:   options.TTL,
+		conns: make(map[string][]*poolConn),
+	}
+}
+
+func (p *pool) Close() error {
+	p.Lock()
+	for k, c := range p.conns {
+		for _, conn := range c {
+			conn.Client.Close()
+		}
+		delete(p.conns, k)
+	}
+	p.Unlock()
+	return nil
+}
+
+// NoOp the Close since we manage it
+func (p *poolConn) Close() error {
+	return nil
+}
+
+func (p *poolConn) Id() string {
+	return p.id
+}
+
+func (p *poolConn) Created() time.Time {
+	return p.created
+}
+
+func (p *pool) Get(addr string, opts ...transport.DialOption) (Conn, error) {
+	p.Lock()
+	conns := p.conns[addr]
+
+	// while we have conns check age and then return one
+	// otherwise we'll create a new conn
+	for len(conns) > 0 {
+		conn := conns[len(conns)-1]
+		conns = conns[:len(conns)-1]
+		p.conns[addr] = conns
+
+		// if conn is old kill it and move on
+		if d := time.Since(conn.Created()); d > p.ttl {
+			conn.Client.Close()
+			continue
+		}
+
+		// we got a good conn, lets unlock and return it
+		p.Unlock()
+
+		return conn, nil
+	}
+
+	p.Unlock()
+
+	// create new conn
+	c, err := p.tr.Dial(addr, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return &poolConn{
+		Client:  c,
+		id:      uuid.New().String(),
+		created: time.Now(),
+	}, nil
+}
+
+func (p *pool) Release(conn Conn, err error) error {
+	// don't store the conn if it has errored
+	if err != nil {
+		return conn.(*poolConn).Client.Close()
+	}
+
+	// otherwise put it back for reuse
+	p.Lock()
+	conns := p.conns[conn.Remote()]
+	if len(conns) >= p.size {
+		p.Unlock()
+		return conn.(*poolConn).Client.Close()
+	}
+	p.conns[conn.Remote()] = append(conns, conn.(*poolConn))
+	p.Unlock()
+
+	return nil
+}

client/pool/default_test.go

@@ -1,4 +1,4 @@
-package client
+package pool
 
 import (
 	"testing"
@@ -9,12 +9,17 @@ import (
 )
 
 func testPool(t *testing.T, size int, ttl time.Duration) {
-	// zero pool
-	p := newPool(size, ttl)
-
 	// mock transport
 	tr := memory.NewTransport()
 
+	options := Options{
+		TTL:       ttl,
+		Size:      size,
+		Transport: tr,
+	}
+	// zero pool
+	p := newPool(options)
+
 	// listen
 	l, err := tr.Listen(":0")
 	if err != nil {
@@ -43,7 +48,7 @@ func testPool(t *testing.T, size int, ttl time.Duration) {
 
 	for i := 0; i < 10; i++ {
 		// get a conn
-		c, err := p.getConn(l.Addr(), tr)
+		c, err := p.Get(l.Addr())
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -67,7 +72,7 @@ func testPool(t *testing.T, size int, ttl time.Duration) {
 		}
 
 		// release the conn
-		p.release(l.Addr(), c, nil)
+		p.Release(c, nil)
 
 		p.Lock()
 		if i := len(p.conns[l.Addr()]); i > size {
@@ -78,7 +83,7 @@ func testPool(t *testing.T, size int, ttl time.Duration) {
 	}
 }
 
-func TestRPCPool(t *testing.T) {
+func TestClientPool(t *testing.T) {
 	testPool(t, 0, time.Minute)
 	testPool(t, 2, time.Minute)
 }

client/pool/options.go

@@ -0,0 +1,33 @@
+package pool
+
+import (
+	"time"
+
+	"github.com/micro/go-micro/transport"
+)
+
+type Options struct {
+	Transport transport.Transport
+	TTL       time.Duration
+	Size      int
+}
+
+type Option func(*Options)
+
+func Size(i int) Option {
+	return func(o *Options) {
+		o.Size = i
+	}
+}
+
+func Transport(t transport.Transport) Option {
+	return func(o *Options) {
+		o.Transport = t
+	}
+}
+
+func TTL(t time.Duration) Option {
+	return func(o *Options) {
+		o.TTL = t
+	}
+}

client/pool/pool.go

@@ -0,0 +1,35 @@
+// Package pool is a connection pool
+package pool
+
+import (
+	"time"
+
+	"github.com/micro/go-micro/transport"
+)
+
+// Pool is an interface for connection pooling
+type Pool interface {
+	// Close the pool
+	Close() error
+	// Get a connection
+	Get(addr string, opts ...transport.DialOption) (Conn, error)
+	// Releaes the connection
+	Release(c Conn, status error) error
+}
+
+type Conn interface {
+	// unique id of connection
+	Id() string
+	// time it was created
+	Created() time.Time
+	// embedded connection
+	transport.Client
+}
+
+func NewPool(opts ...Option) Pool {
+	var options Options
+	for _, o := range opts {
+		o(&options)
+	}
+	return newPool(options)
+}

client/rpc_client.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/google/uuid"
 	"github.com/micro/go-micro/broker"
+	"github.com/micro/go-micro/client/pool"
 	"github.com/micro/go-micro/client/selector"
 	"github.com/micro/go-micro/codec"
 	"github.com/micro/go-micro/errors"
@@ -22,17 +23,23 @@ import (
 type rpcClient struct {
 	once sync.Once
 	opts Options
-	pool *pool
+	pool pool.Pool
 	seq  uint64
 }
 
 func newRpcClient(opt ...Option) Client {
 	opts := newOptions(opt...)
 
+	p := pool.NewPool(
+		pool.Size(opts.PoolSize),
+		pool.TTL(opts.PoolTTL),
+		pool.Transport(opts.Transport),
+	)
+
 	rc := &rpcClient{
 		once: sync.Once{},
 		opts: opts,
-		pool: newPool(opts.PoolSize, opts.PoolTTL),
+		pool: p,
 		seq:  0,
 	}
 
@@ -90,13 +97,13 @@ func (r *rpcClient) call(ctx context.Context, node *registry.Node, req Request,
 	}
 
 	var grr error
-	c, err := r.pool.getConn(address, r.opts.Transport, transport.WithTimeout(opts.DialTimeout))
+	c, err := r.pool.Get(address, transport.WithTimeout(opts.DialTimeout))
 	if err != nil {
 		return errors.InternalServerError("go.micro.client", "connection error: %v", err)
 	}
 	defer func() {
 		// defer execution of release
-		r.pool.release(address, c, grr)
+		r.pool.Release(c, grr)
 	}()
 
 	seq := atomic.LoadUint64(&r.seq)
@@ -245,17 +252,22 @@ func (r *rpcClient) stream(ctx context.Context, node *registry.Node, req Request
 func (r *rpcClient) Init(opts ...Option) error {
 	size := r.opts.PoolSize
 	ttl := r.opts.PoolTTL
+	tr := r.opts.Transport
 
 	for _, o := range opts {
 		o(&r.opts)
 	}
 
 	// update pool configuration if the options changed
-	if size != r.opts.PoolSize || ttl != r.opts.PoolTTL {
+	if size != r.opts.PoolSize || ttl != r.opts.PoolTTL || tr != r.opts.Transport {
-		r.pool.Lock()
+		// close existing pool
-		r.pool.size = r.opts.PoolSize
+		r.pool.Close()
-		r.pool.ttl = int64(r.opts.PoolTTL.Seconds())
+		// create new pool
-		r.pool.Unlock()
+		r.pool = pool.NewPool(
+			pool.Size(r.opts.PoolSize),
+			pool.TTL(r.opts.PoolTTL),
+			pool.Transport(r.opts.Transport),
+		)
 	}
 
 	return nil

client/rpc_pool.go

@@ -1,87 +0,0 @@
-package client
-
-import (
-	"sync"
-	"time"
-
-	"github.com/micro/go-micro/transport"
-)
-
-type pool struct {
-	size int
-	ttl  int64
-
-	sync.Mutex
-	conns map[string][]*poolConn
-}
-
-type poolConn struct {
-	transport.Client
-	created int64
-}
-
-func newPool(size int, ttl time.Duration) *pool {
-	return &pool{
-		size:  size,
-		ttl:   int64(ttl.Seconds()),
-		conns: make(map[string][]*poolConn),
-	}
-}
-
-// NoOp the Close since we manage it
-func (p *poolConn) Close() error {
-	return nil
-}
-
-func (p *pool) getConn(addr string, tr transport.Transport, opts ...transport.DialOption) (*poolConn, error) {
-	p.Lock()
-	conns := p.conns[addr]
-	now := time.Now().Unix()
-
-	// while we have conns check age and then return one
-	// otherwise we'll create a new conn
-	for len(conns) > 0 {
-		conn := conns[len(conns)-1]
-		conns = conns[:len(conns)-1]
-		p.conns[addr] = conns
-
-		// if conn is old kill it and move on
-		if d := now - conn.created; d > p.ttl {
-			conn.Client.Close()
-			continue
-		}
-
-		// we got a good conn, lets unlock and return it
-		p.Unlock()
-
-		return conn, nil
-	}
-
-	p.Unlock()
-
-	// create new conn
-	c, err := tr.Dial(addr, opts...)
-	if err != nil {
-		return nil, err
-	}
-	return &poolConn{c, time.Now().Unix()}, nil
-}
-
-func (p *pool) release(addr string, conn *poolConn, err error) {
-	// don't store the conn if it has errored
-	if err != nil {
-		conn.Client.Close()
-		return
-	}
-
-	// otherwise put it back for reuse
-	p.Lock()
-	conns := p.conns[addr]
-	if len(conns) >= p.size {
-		p.Unlock()
-		conn.Client.Close()
-		return
-	}
-	p.conns[addr] = append(conns, conn)
-	p.Unlock()
-}