config: Host support IPv4/IPv6 (#128)

* config: Host support IPv4/IPv6

* config: Add QINGSTOR_ENABLE_DUAL_STACK env variable

* config: Modify error message

config/config.go

@@ -19,6 +19,7 @@ package config
 import (
 	"errors"
 	"io/ioutil"
+	"net"
 	"net/http"
 	"net/url"
 	"os"
@@ -51,6 +52,8 @@ type Config struct {
 
 	EnableVirtualHostStyle bool `yaml:"enable_virtual_host_style"`
 
+	EnableDualStack bool `yaml:"enable_dual_stack"`
+
 	HTTPSettings HTTPClientSettings
 
 	Connection *http.Client
@@ -160,6 +163,20 @@ func (c *Config) Check() (err error) {
 		}
 	}
 
+	ip := net.ParseIP(c.Host)
+	if c.EnableVirtualHostStyle {
+		if ip != nil {
+			err = errors.New("Host is ip, cannot virtual host style")
+			return
+		}
+	}
+
+	if !c.EnableDualStack {
+		if ip != nil && ip.To4() == nil {
+			err = errors.New("Host is IPv6 address, enable_dual_stack should be true")
+			return
+		}
+	}
 	return
 }
 
@@ -227,12 +244,12 @@ func (c *Config) LoadConfigFromContent(content []byte) (err error) {
 		return
 	}
 
-	err = c.Check()
+	err = c.parseEndpoint()
 	if err != nil {
 		return
 	}
 
-	err = c.parseEndpoint()
+	err = c.Check()
 	if err != nil {
 		return
 	}
@@ -270,6 +287,10 @@ func (c *Config) readCredentialFromEnv() (err error) {
 	if err != nil {
 		return
 	}
+	c.EnableDualStack, err = strconv.ParseBool(os.Getenv(EnvEnableDualStack))
+	if err != nil {
+		return
+	}
 	return nil
 }
 
@@ -301,7 +322,11 @@ func (c *Config) InitHTTPClient() {
 	// when the network is "tcp" and the destination is a host name
 	// with both IPv4 and IPv6 addresses. This allows a client to
 	// tolerate networks where one address family is silently broken
-	dialer.DualStack = c.HTTPSettings.DualStack
+	dialer.DualStack = c.EnableDualStack
+	if !dialer.DualStack {
+		negativeValue, _ := time.ParseDuration("-300ms")
+		dialer.FallbackDelay = negativeValue
+	}
 	c.Connection = &http.Client{
 		// We do not use the timeout in http client,
 		// because this timeout is for the whole http body read/write,

config/config_test.go

@@ -129,3 +129,29 @@ func TestParseEndpoint(t *testing.T) {
 		})
 	}
 }
+
+func TestSupportIP(t *testing.T) {
+	// Host is ip address, enable virtual host style
+	c := Config{
+		AccessKeyID:            "AccessKeyID",
+		SecretAccessKey:        "SecretAccessKey",
+		Endpoint:               "https://192.168.0.1:443",
+		EnableVirtualHostStyle: true,
+	}
+	err := c.parseEndpoint()
+	assert.Nil(t, err)
+	err = c.Check()
+	assert.NotNil(t, err)
+
+	//
+	c = Config{
+		AccessKeyID:     "AccessKeyID",
+		SecretAccessKey: "SecretAccessKey",
+		Endpoint:        "https://2001:db8::68:443",
+		EnableDualStack: false,
+	}
+	err = c.parseEndpoint()
+	assert.Nil(t, err)
+	err = c.Check()
+	assert.NotNil(t, err)
+}

config/contract.go

@@ -57,6 +57,9 @@ const (
 
 	// EnvEnableVirtualHostStyle is config envrionment variable.
 	EnvEnableVirtualHostStyle = "QINGSTOR_ENABLE_VIRTUAL_HOST_STYLE"
+
+	// EnvEnableDualStack is config envrionment variable.
+	EnvEnableDualStack = "QINGSTOR_ENABLE_DUAL_STACK"
 )
 
 // GetUserConfigFilePath returns the user config file path.