- remove Lease.IDOptions and update corresponding struct / function

- add NewReleaseFromLease and update Client.Release() accordingly
- update lease_test.go accordingly
- remove example_lease_test.go

Signed-off-by: Hu Jun <hujun.work@gmail.com>

1 files changed, 24 insertions, 33 deletions

diff --git a/dhcpv4/nclient4/lease.go b/dhcpv4/nclient4/lease.go
index 838e39b..bd684b0 100644
--- a/dhcpv4/nclient4/lease.go
+++ b/dhcpv4/nclient4/lease.go
@@ -1,4 +1,4 @@
-//This is lease support for nclient4
+// This is lease support for nclient4
 
 package nclient4
 
@@ -10,51 +10,42 @@ import (
 	"github.com/insomniacslk/dhcp/dhcpv4"
 )
 
-//Lease contains a DHCPv4 lease after DORA.
-//note: Lease doesn't include binding interface name
+// Lease contains a DHCPv4 lease after DORA.
+// note: Lease doesn't include binding interface name
 type Lease struct {
 	Offer        *dhcpv4.DHCPv4
 	ACK          *dhcpv4.DHCPv4
 	CreationTime time.Time
-	IDOptions    dhcpv4.Options //DHCPv4 options to identify the client like client-id, option82/remote-id
 }
 
-// WithClientIDOptions configures a list of DHCPv4 option code that DHCP server
-// uses to identify client, beside the MAC address.
-func WithClientIDOptions(cidl dhcpv4.OptionCodeList) ClientOpt {
-	return func(c *Client) (err error) {
-		c.clientIDOptions = cidl
-		return
-	}
-}
-
-//Release send DHCPv4 release messsage to server, based on specified lease.
-//release is sent as unicast per RFC2131, section 4.4.4.
-//Note: some DHCP server requries of using assigned IP address as source IP,
-//use nclient4.WithUnicast to create client for such case.
-func (c *Client) Release(lease *Lease) error {
-	if lease == nil {
-		return fmt.Errorf("lease is nil")
-	}
-	modList := []dhcpv4.Modifier{
+// NewReleaseFromLease creates a DHCPv4 Release message from the lease.
+// default Release message without any Modifer is created as following:
+//  - option Message Type is Release
+//  - ClientIP is set to lease.ACK.YourIPAddr
+//  - ClientHWAddr is set to lease.ACK.ClientHWAddr
+//  - Unicast
+//  - option Server Identifier is set to ServerIdentifier of lease.ACK
+func NewReleaseFromLease(lease *Lease, modifiers ...dhcpv4.Modifier) (*dhcpv4.DHCPv4, error) {
+	return dhcpv4.New(dhcpv4.PrependModifiers(modifiers,
 		dhcpv4.WithMessageType(dhcpv4.MessageTypeRelease),
 		dhcpv4.WithClientIP(lease.ACK.YourIPAddr),
 		dhcpv4.WithHwAddr(lease.ACK.ClientHWAddr),
 		dhcpv4.WithBroadcast(false),
 		dhcpv4.WithOption(dhcpv4.OptServerIdentifier(lease.ACK.ServerIdentifier())),
-	}
+	)...)
+}
 
-	req, err := dhcpv4.New(modList...)
-	if err != nil {
-		return err
+// Release send DHCPv4 release messsage to server, based on specified lease.
+// release is sent as unicast per RFC2131, section 4.4.4.
+// Note: some DHCP server requries of using assigned IP address as source IP,
+// use nclient4.WithUnicast to create client for such case.
+func (c *Client) Release(lease *Lease, modifiers ...dhcpv4.Modifier) error {
+	if lease == nil {
+		return fmt.Errorf("lease is nil")
 	}
-	//This is to make sure use same client identification options used during
-	//DORA, so that DHCP server could identify the required lease
-	for t := range lease.IDOptions {
-		req.UpdateOption(
-			dhcpv4.OptGeneric(dhcpv4.GenericOptionCode(t),
-				lease.IDOptions.Get(dhcpv4.GenericOptionCode(t))),
-		)
+	req, err := NewReleaseFromLease(lease, modifiers...)
+	if err != nil {
+		return fmt.Errorf("fail to create release request,%w", err)
 	}
 	_, err = c.conn.WriteTo(req.ToBytes(), &net.UDPAddr{IP: lease.ACK.Options.Get(dhcpv4.OptionServerIdentifier), Port: ServerPort})
 	if err == nil {