support http connect timeout setting (#27)

* connection support timeout settings.

* use transport dial timeout to replace http timeout.

* fix config test.

config/config.go

@@ -24,6 +24,8 @@ import (
 
 	"github.com/yunify/qingcloud-sdk-go/logger"
 	"github.com/yunify/qingcloud-sdk-go/utils"
+	"time"
+	"net"
 )
 
 // A Config stores a configuration of this sdk.
@@ -36,6 +38,7 @@ type Config struct {
 	Protocol          string `yaml:"protocol"`
 	URI               string `yaml:"uri"`
 	ConnectionRetries int    `yaml:"connection_retries"`
+	ConnectionTimeout int    `yaml:"connection_timeout"`
 
 	LogLevel string `yaml:"log_level"`
 
@@ -66,7 +69,16 @@ func NewDefault() (*Config, error) {
 	if err != nil {
 		return nil, err
 	}
-	config.Connection = &http.Client{}
+
+	timeout := time.Duration(config.ConnectionTimeout) * time.Second
+	transport := &http.Transport{
+		Dial: func (network, addr string) (net.Conn, error) {
+		return net.DialTimeout(network, addr, timeout)
+		},
+	}
+	config.Connection = &http.Client{
+		Transport:transport,
+	}
 
 	return config, nil
 }
@@ -126,5 +138,15 @@ func (c *Config) LoadConfigFromContent(content []byte) error {
 
 	logger.SetLevel(c.LogLevel)
 
+	timeout := time.Duration(c.ConnectionTimeout) * time.Second
+	transport := &http.Transport{
+		Dial: func (network, addr string) (net.Conn, error) {
+			return net.DialTimeout(network, addr, timeout)
+		},
+	}
+	c.Connection = &http.Client{
+		Transport:transport,
+	}
+
 	return nil
-}
+}

config/contract.go

@@ -35,6 +35,7 @@ port: 443
 protocol: 'https'
 uri: '/iaas'
 connection_retries: 3
+connection_timeout: 30
 
 # Valid log levels are "debug", "info", "warn", "error", and "fatal".
 log_level: 'warn'