migrated multi host connection pool from godropbox package

removing unneeded dependencies, which involved etcd versions.

6 files changed, 643 insertions, 0 deletions

diff --git a/weed/wdclient/net2/base_connection_pool.go b/weed/wdclient/net2/base_connection_pool.go
new file mode 100644
index 000000000..5cc037d0f
--- /dev/null
+++ b/weed/wdclient/net2/base_connection_pool.go
@@ -0,0 +1,159 @@
+package net2
+
+import (
+	"net"
+	"strings"
+	"time"
+
+	rp "github.com/chrislusf/seaweedfs/weed/wdclient/resource_pool"
+)
+
+const defaultDialTimeout = 1 * time.Second
+
+func defaultDialFunc(network string, address string) (net.Conn, error) {
+	return net.DialTimeout(network, address, defaultDialTimeout)
+}
+
+func parseResourceLocation(resourceLocation string) (
+	network string,
+	address string) {
+
+	idx := strings.Index(resourceLocation, " ")
+	if idx >= 0 {
+		return resourceLocation[:idx], resourceLocation[idx+1:]
+	}
+
+	return "", resourceLocation
+}
+
+// A thin wrapper around the underlying resource pool.
+type connectionPoolImpl struct {
+	options ConnectionOptions
+
+	pool rp.ResourcePool
+}
+
+// This returns a connection pool where all connections are connected
+// to the same (network, address)
+func newBaseConnectionPool(
+	options ConnectionOptions,
+	createPool func(rp.Options) rp.ResourcePool) ConnectionPool {
+
+	dial := options.Dial
+	if dial == nil {
+		dial = defaultDialFunc
+	}
+
+	openFunc := func(loc string) (interface{}, error) {
+		network, address := parseResourceLocation(loc)
+		return dial(network, address)
+	}
+
+	closeFunc := func(handle interface{}) error {
+		return handle.(net.Conn).Close()
+	}
+
+	poolOptions := rp.Options{
+		MaxActiveHandles:   options.MaxActiveConnections,
+		MaxIdleHandles:     options.MaxIdleConnections,
+		MaxIdleTime:        options.MaxIdleTime,
+		OpenMaxConcurrency: options.DialMaxConcurrency,
+		Open:               openFunc,
+		Close:              closeFunc,
+		NowFunc:            options.NowFunc,
+	}
+
+	return &connectionPoolImpl{
+		options: options,
+		pool:    createPool(poolOptions),
+	}
+}
+
+// This returns a connection pool where all connections are connected
+// to the same (network, address)
+func NewSimpleConnectionPool(options ConnectionOptions) ConnectionPool {
+	return newBaseConnectionPool(options, rp.NewSimpleResourcePool)
+}
+
+// This returns a connection pool that manages multiple (network, address)
+// entries.  The connections to each (network, address) entry acts
+// independently. For example ("tcp", "localhost:11211") could act as memcache
+// shard 0 and ("tcp", "localhost:11212") could act as memcache shard 1.
+func NewMultiConnectionPool(options ConnectionOptions) ConnectionPool {
+	return newBaseConnectionPool(
+		options,
+		func(poolOptions rp.Options) rp.ResourcePool {
+			return rp.NewMultiResourcePool(poolOptions, nil)
+		})
+}
+
+// See ConnectionPool for documentation.
+func (p *connectionPoolImpl) NumActive() int32 {
+	return p.pool.NumActive()
+}
+
+// See ConnectionPool for documentation.
+func (p *connectionPoolImpl) ActiveHighWaterMark() int32 {
+	return p.pool.ActiveHighWaterMark()
+}
+
+// This returns the number of alive idle connections.  This method is not part
+// of ConnectionPool's API.  It is used only for testing.
+func (p *connectionPoolImpl) NumIdle() int {
+	return p.pool.NumIdle()
+}
+
+// BaseConnectionPool can only register a single (network, address) entry.
+// Register should be call before any Get calls.
+func (p *connectionPoolImpl) Register(network string, address string) error {
+	return p.pool.Register(network + " " + address)
+}
+
+// BaseConnectionPool has nothing to do on Unregister.
+func (p *connectionPoolImpl) Unregister(network string, address string) error {
+	return nil
+}
+
+func (p *connectionPoolImpl) ListRegistered() []NetworkAddress {
+	result := make([]NetworkAddress, 0, 1)
+	for _, location := range p.pool.ListRegistered() {
+		network, address := parseResourceLocation(location)
+
+		result = append(
+			result,
+			NetworkAddress{
+				Network: network,
+				Address: address,
+			})
+	}
+	return result
+}
+
+// This gets an active connection from the connection pool.  Note that network
+// and address arguments are ignored (The connections with point to the
+// network/address provided by the first Register call).
+func (p *connectionPoolImpl) Get(
+	network string,
+	address string) (ManagedConn, error) {
+
+	handle, err := p.pool.Get(network + " " + address)
+	if err != nil {
+		return nil, err
+	}
+	return NewManagedConn(network, address, handle, p, p.options), nil
+}
+
+// See ConnectionPool for documentation.
+func (p *connectionPoolImpl) Release(conn ManagedConn) error {
+	return conn.ReleaseConnection()
+}
+
+// See ConnectionPool for documentation.
+func (p *connectionPoolImpl) Discard(conn ManagedConn) error {
+	return conn.DiscardConnection()
+}
+
+// See ConnectionPool for documentation.
+func (p *connectionPoolImpl) EnterLameDuckMode() {
+	p.pool.EnterLameDuckMode()
+}
diff --git a/weed/wdclient/net2/connection_pool.go b/weed/wdclient/net2/connection_pool.go
new file mode 100644
index 000000000..5b8d4d232
--- /dev/null
+++ b/weed/wdclient/net2/connection_pool.go
@@ -0,0 +1,97 @@
+package net2
+
+import (
+	"net"
+	"time"
+)
+
+type ConnectionOptions struct {
+	// The maximum number of connections that can be active per host at any
+	// given time (A non-positive value indicates the number of connections
+	// is unbounded).
+	MaxActiveConnections int32
+
+	// The maximum number of idle connections per host that are kept alive by
+	// the connection pool.
+	MaxIdleConnections uint32
+
+	// The maximum amount of time an idle connection can alive (if specified).
+	MaxIdleTime *time.Duration
+
+	// This limits the number of concurrent Dial calls (there's no limit when
+	// DialMaxConcurrency is non-positive).
+	DialMaxConcurrency int
+
+	// Dial specifies the dial function for creating network connections.
+	// If Dial is nil, net.DialTimeout is used, with timeout set to 1 second.
+	Dial func(network string, address string) (net.Conn, error)
+
+	// This specifies the now time function.  When the function is non-nil, the
+	// connection pool will use the specified function instead of time.Now to
+	// generate the current time.
+	NowFunc func() time.Time
+
+	// This specifies the timeout for any Read() operation.
+	// Note that setting this to 0 (i.e. not setting it) will make
+	// read operations block indefinitely.
+	ReadTimeout time.Duration
+
+	// This specifies the timeout for any Write() operation.
+	// Note that setting this to 0 (i.e. not setting it) will make
+	// write operations block indefinitely.
+	WriteTimeout time.Duration
+}
+
+func (o ConnectionOptions) getCurrentTime() time.Time {
+	if o.NowFunc == nil {
+		return time.Now()
+	} else {
+		return o.NowFunc()
+	}
+}
+
+// A generic interface for managed connection pool.  All connection pool
+// implementations must be threadsafe.
+type ConnectionPool interface {
+	// This returns the number of active connections that are on loan.
+	NumActive() int32
+
+	// This returns the highest number of active connections for the entire
+	// lifetime of the pool.
+	ActiveHighWaterMark() int32
+
+	// This returns the number of idle connections that are in the pool.
+	NumIdle() int
+
+	// This associates (network, address) to the connection pool; afterwhich,
+	// the user can get connections to (network, address).
+	Register(network string, address string) error
+
+	// This dissociate (network, address) from the connection pool;
+	// afterwhich, the user can no longer get connections to
+	// (network, address).
+	Unregister(network string, address string) error
+
+	// This returns the list of registered (network, address) entries.
+	ListRegistered() []NetworkAddress
+
+	// This gets an active connection from the connection pool.  The connection
+	// will remain active until one of the following is called:
+	//  1. conn.ReleaseConnection()
+	//  2. conn.DiscardConnection()
+	//  3. pool.Release(conn)
+	//  4. pool.Discard(conn)
+	Get(network string, address string) (ManagedConn, error)
+
+	// This releases an active connection back to the connection pool.
+	Release(conn ManagedConn) error
+
+	// This discards an active connection from the connection pool.
+	Discard(conn ManagedConn) error
+
+	// Enter the connection pool into lame duck mode.  The connection pool
+	// will no longer return connections, and all idle connections are closed
+	// immediately (including active connections that are released back to the
+	// pool afterward).
+	EnterLameDuckMode()
+}
diff --git a/weed/wdclient/net2/doc.go b/weed/wdclient/net2/doc.go
new file mode 100644
index 000000000..f4d6552e4
--- /dev/null
+++ b/weed/wdclient/net2/doc.go
@@ -0,0 +1,6 @@
+// net2 is a collection of functions meant to supplement the capabilities
+// provided by the standard "net" package.
+package net2
+
+// copied from https://github.com/dropbox/godropbox/tree/master/net2
+// removed other dependencies
\ No newline at end of file
diff --git a/weed/wdclient/net2/ip.go b/weed/wdclient/net2/ip.go
new file mode 100644
index 000000000..60e46342f
--- /dev/null
+++ b/weed/wdclient/net2/ip.go
@@ -0,0 +1,177 @@
+package net2
+
+import (
+	"fmt"
+	"log"
+	"net"
+	"os"
+	"strings"
+	"sync"
+)
+
+var myHostname string
+var myHostnameOnce sync.Once
+
+// Like os.Hostname but caches first successful result, making it cheap to call it
+// over and over.
+// It will also crash whole process if fetching Hostname fails!
+func MyHostname() string {
+	myHostnameOnce.Do(func() {
+		var err error
+		myHostname, err = os.Hostname()
+		if err != nil {
+			log.Fatal(err)
+		}
+	})
+	return myHostname
+}
+
+var myIp4 *net.IPAddr
+var myIp4Once sync.Once
+
+// Resolves `MyHostname()` to an Ip4 address. Caches first successful result, making it
+// cheap to call it over and over.
+// It will also crash whole process if resolving the IP fails!
+func MyIp4() *net.IPAddr {
+	myIp4Once.Do(func() {
+		var err error
+		myIp4, err = net.ResolveIPAddr("ip4", MyHostname())
+		if err != nil {
+			log.Fatal(err)
+		}
+	})
+	return myIp4
+}
+
+var myIp6 *net.IPAddr
+var myIp6Once sync.Once
+
+// Resolves `MyHostname()` to an Ip6 address. Caches first successful result, making it
+// cheap to call it over and over.
+// It will also crash whole process if resolving the IP fails!
+func MyIp6() *net.IPAddr {
+	myIp6Once.Do(func() {
+		var err error
+		myIp6, err = net.ResolveIPAddr("ip6", MyHostname())
+		if err != nil {
+			log.Fatal(err)
+		}
+	})
+	return myIp6
+}
+
+// This returns the list of local ip addresses which other hosts can connect
+// to (NOTE: Loopback ip is ignored).
+// Also resolves Hostname to an address and adds it to the list too, so
+// IPs from /etc/hosts can work too.
+func GetLocalIPs() ([]*net.IP, error) {
+	hostname, err := os.Hostname()
+	if err != nil {
+		return nil, fmt.Errorf("Failed to lookup hostname: %v", err)
+	}
+	// Resolves IP Address from Hostname, this way overrides in /etc/hosts
+	// can work too for IP resolution.
+	ipInfo, err := net.ResolveIPAddr("ip4", hostname)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to resolve ip: %v", err)
+	}
+	ips := []*net.IP{&ipInfo.IP}
+
+	// TODO(zviad): Is rest of the code really necessary?
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return nil, fmt.Errorf( "Failed to get interface addresses: %v", err)
+	}
+	for _, addr := range addrs {
+		ipnet, ok := addr.(*net.IPNet)
+		if !ok {
+			continue
+		}
+
+		if ipnet.IP.IsLoopback() {
+			continue
+		}
+
+		ips = append(ips, &ipnet.IP)
+	}
+	return ips, nil
+}
+
+var localhostIPNets []*net.IPNet
+
+func init() {
+	for _, mask := range []string{"127.0.0.1/8", "::1/128"} {
+		_, ipnet, err := net.ParseCIDR(mask)
+		if err != nil {
+			panic(err)
+		}
+		localhostIPNets = append(localhostIPNets, ipnet)
+	}
+}
+
+func IsLocalhostIp(ipStr string) bool {
+	ip := net.ParseIP(ipStr)
+	if ip == nil {
+		return false
+	}
+	for _, ipnet := range localhostIPNets {
+		if ipnet.Contains(ip) {
+			return true
+		}
+	}
+	return false
+}
+
+// Given a host string, return true if the host is an ip (v4/v6) localhost.
+func IsLocalhost(host string) bool {
+	return IsLocalhostIp(host) ||
+		host == "localhost" ||
+		host == "ip6-localhost" ||
+		host == "ipv6-localhost"
+}
+
+// Resolves hostnames in addresses to actual IP4 addresses. Skips all invalid addresses
+// and all addresses that can't be resolved.
+// `addrs` are assumed to be of form: ["<hostname>:<port>", ...]
+// Returns an error in addition to resolved addresses if not all resolutions succeed.
+func ResolveIP4s(addrs []string) ([]string, error) {
+	resolvedAddrs := make([]string, 0, len(addrs))
+	var lastErr error
+
+	for _, server := range addrs {
+		hostPort := strings.Split(server, ":")
+		if len(hostPort) != 2 {
+			lastErr = fmt.Errorf("Skipping invalid address: %s", server)
+			continue
+		}
+
+		ip, err := net.ResolveIPAddr("ip4", hostPort[0])
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		resolvedAddrs = append(resolvedAddrs, ip.IP.String()+":"+hostPort[1])
+	}
+	return resolvedAddrs, lastErr
+}
+
+func LookupValidAddrs() (map[string]bool, error) {
+	hostName, err := os.Hostname()
+	if err != nil {
+		return nil, err
+	}
+	addrs, err := net.LookupHost(hostName)
+	if err != nil {
+		return nil, err
+	}
+	validAddrs := make(map[string]bool)
+	validAddrs[hostName] = true
+	for _, addr := range addrs {
+		validAddrs[addr] = true
+	}
+	// Special case localhost/127.0.0.1 so that this works on devVMs. It should
+	// have no affect in production.
+	validAddrs["127.0.0.1"] = true
+	validAddrs["localhost"] = true
+	return validAddrs, nil
+}
diff --git a/weed/wdclient/net2/managed_connection.go b/weed/wdclient/net2/managed_connection.go
new file mode 100644
index 000000000..a886210d1
--- /dev/null
+++ b/weed/wdclient/net2/managed_connection.go
@@ -0,0 +1,185 @@
+package net2
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"errors"
+	"github.com/chrislusf/seaweedfs/weed/wdclient/resource_pool"
+)
+
+// Dial's arguments.
+type NetworkAddress struct {
+	Network string
+	Address string
+}
+
+// A connection managed by a connection pool.  NOTE: SetDeadline,
+// SetReadDeadline and SetWriteDeadline are disabled for managed connections.
+// (The deadlines are set by the connection pool).
+type ManagedConn interface {
+	net.Conn
+
+	// This returns the original (network, address) entry used for creating
+	// the connection.
+	Key() NetworkAddress
+
+	// This returns the underlying net.Conn implementation.
+	RawConn() net.Conn
+
+	// This returns the connection pool which owns this connection.
+	Owner() ConnectionPool
+
+	// This indictes a user is done with the connection and releases the
+	// connection back to the connection pool.
+	ReleaseConnection() error
+
+	// This indicates the connection is an invalid state, and that the
+	// connection should be discarded from the connection pool.
+	DiscardConnection() error
+}
+
+// A physical implementation of ManagedConn
+type managedConnImpl struct {
+	addr    NetworkAddress
+	handle  resource_pool.ManagedHandle
+	pool    ConnectionPool
+	options ConnectionOptions
+}
+
+// This creates a managed connection wrapper.
+func NewManagedConn(
+	network string,
+	address string,
+	handle resource_pool.ManagedHandle,
+	pool ConnectionPool,
+	options ConnectionOptions) ManagedConn {
+
+	addr := NetworkAddress{
+		Network: network,
+		Address: address,
+	}
+
+	return &managedConnImpl{
+		addr:    addr,
+		handle:  handle,
+		pool:    pool,
+		options: options,
+	}
+}
+
+func (c *managedConnImpl) rawConn() (net.Conn, error) {
+	h, err := c.handle.Handle()
+	return h.(net.Conn), err
+}
+
+// See ManagedConn for documentation.
+func (c *managedConnImpl) RawConn() net.Conn {
+	h, _ := c.handle.Handle()
+	return h.(net.Conn)
+}
+
+// See ManagedConn for documentation.
+func (c *managedConnImpl) Key() NetworkAddress {
+	return c.addr
+}
+
+// See ManagedConn for documentation.
+func (c *managedConnImpl) Owner() ConnectionPool {
+	return c.pool
+}
+
+// See ManagedConn for documentation.
+func (c *managedConnImpl) ReleaseConnection() error {
+	return c.handle.Release()
+}
+
+// See ManagedConn for documentation.
+func (c *managedConnImpl) DiscardConnection() error {
+	return c.handle.Discard()
+}
+
+// See net.Conn for documentation
+func (c *managedConnImpl) Read(b []byte) (n int, err error) {
+	conn, err := c.rawConn()
+	if err != nil {
+		return 0, err
+	}
+
+	if c.options.ReadTimeout > 0 {
+		deadline := c.options.getCurrentTime().Add(c.options.ReadTimeout)
+		_ = conn.SetReadDeadline(deadline)
+	}
+	n, err = conn.Read(b)
+	if err != nil {
+		var localAddr string
+		if conn.LocalAddr() != nil {
+			localAddr = conn.LocalAddr().String()
+		} else {
+			localAddr = "(nil)"
+		}
+
+		var remoteAddr string
+		if conn.RemoteAddr() != nil {
+			remoteAddr = conn.RemoteAddr().String()
+		} else {
+			remoteAddr = "(nil)"
+		}
+		err = fmt.Errorf("Read error from host: %s <-> %s: %v", localAddr, remoteAddr, err)
+	}
+	return
+}
+
+// See net.Conn for documentation
+func (c *managedConnImpl) Write(b []byte) (n int, err error) {
+	conn, err := c.rawConn()
+	if err != nil {
+		return 0, err
+	}
+
+	if c.options.WriteTimeout > 0 {
+		deadline := c.options.getCurrentTime().Add(c.options.WriteTimeout)
+		_ = conn.SetWriteDeadline(deadline)
+	}
+	n, err = conn.Write(b)
+	if err != nil {
+		err = fmt.Errorf("Write error: %v", err)
+	}
+	return
+}
+
+// See net.Conn for documentation
+func (c *managedConnImpl) Close() error {
+	return c.handle.Discard()
+}
+
+// See net.Conn for documentation
+func (c *managedConnImpl) LocalAddr() net.Addr {
+	conn, _ := c.rawConn()
+	return conn.LocalAddr()
+}
+
+// See net.Conn for documentation
+func (c *managedConnImpl) RemoteAddr() net.Addr {
+	conn, _ := c.rawConn()
+	return conn.RemoteAddr()
+}
+
+// SetDeadline is disabled for managed connection (The deadline is set by
+// us, with respect to the read/write timeouts specified in ConnectionOptions).
+func (c *managedConnImpl) SetDeadline(t time.Time) error {
+	return errors.New("Cannot set deadline for managed connection")
+}
+
+// SetReadDeadline is disabled for managed connection (The deadline is set by
+// us with respect to the read timeout specified in ConnectionOptions).
+func (c *managedConnImpl) SetReadDeadline(t time.Time) error {
+	return errors.New("Cannot set read deadline for managed connection")
+}
+
+// SetWriteDeadline is disabled for managed connection (The deadline is set by
+// us with respect to the write timeout specified in ConnectionOptions).
+func (c *managedConnImpl) SetWriteDeadline(t time.Time) error {
+	return errors.New("Cannot set write deadline for managed connection")
+}
diff --git a/weed/wdclient/net2/port.go b/weed/wdclient/net2/port.go
new file mode 100644
index 000000000..f83adba28
--- /dev/null
+++ b/weed/wdclient/net2/port.go
@@ -0,0 +1,19 @@
+package net2
+
+import (
+	"net"
+	"strconv"
+)
+
+// Returns the port information.
+func GetPort(addr net.Addr) (int, error) {
+	_, lport, err := net.SplitHostPort(addr.String())
+	if err != nil {
+		return -1, err
+	}
+	lportInt, err := strconv.Atoi(lport)
+	if err != nil {
+		return -1, err
+	}
+	return lportInt, nil
+}