Feature subnet

docs/resources/softlayer_subnet.md

@@ -0,0 +1,110 @@
+#### `softlayer_subnet`
+
+`softlayer_subnet` provides portable and static subnets that consist of either IPv4 and IPv6 addresses. Users are able to create 
+public portable subnets, private portable subnets, and public static subnets with an IPv4 option and public portable subnets and public static 
+subnets with an IPv6 option. 
+
+The portable IPv4 subnet is created as a seconday subnet on a VLAN. IP addresses in the portable subnet can be assigned as secondary IP 
+ addresses for SoftLayer resources in the VLAN. Each portable subnet has a default gateway IP address, network IP address, and broadcast 
+ IP address. For example, if a portable subnet is `10.0.0.0/30`, `10.0.0.0` is a network IP address, `10.0.0.1` is a default gateway IP address, 
+ and `10.0.0.3` is a broadcast IP address. Therefore, only `10.0.0.2` can be assigned to SoftLayer resources as a secondary IP address. 
+ Number of usuable IP addresses is `capacity` - 3. If `capacity` is 4, the number of usuable IP addresses is 4 - 3 = 1. If `capacity` is 8, the 
+ number of usuable IP addresses is 8 - 3 = 5. For additional details, refer to [Static and Portable IP blocks](https://knowledgelayer.softlayer.com/articles/static-and-portable-ip-blocks).
+
+The static IPv4 subnet provides secondary IP addresses for primary IP addresses. It provides secondary IP addresses for SoftLayer resources such as 
+virtual servers, bare metal servers, and netscaler VPXs. Suppose that a virtual server requires secondary IP addresses. Then, users can create 
+a static subnet on the public IP address of the virtual server. Unlike the portable subnet, `capacity` is same with a number of usuable IP address. 
+For example, if a static subnet is `10.0.0.0/30`, `capacity` is 4 and four IP addresses(10.0.0.0 ~ 10.0.0.3) can be used as secondary IP addresses. 
+For additional details, refer to [Subnet](https://knowledgelayer.softlayer.com/topic/subnets).
+
+Both the public portable IPv6 subnet and the public static IP only accept `64` as a value of `capacity` attribute. They provide 2^64 IP addresses. For additional detail, refer to [IPv6 address](http://blog.softlayer.com/tag/ipv6)
+
+The following example will create a private portable subnet which has one available IPv4 address. 
+##### Example Usage of portable subnet
+
+```hcl
+# Create a new portable subnet
+resource "softlayer_subnet" "portable_subnet" {
+  type = "Portable"
+  private = true
+  ip_version = 4
+  capacity = 4
+  vlan_id = 1234567
+  notes = "portable_subnet"
+}
+```
+
+The following example will create a public static subnet which has four available IPv4 address.
+##### Example Usage of static subnet
+
+```hcl
+# Create a new static subnet
+resource "softlayer_subnet" "static_subnet" {
+  type = "Static"
+  private = false
+  ip_version = 4
+  capacity = 4
+  endpoint_ip="151.1.1.1"
+  notes = "static_subnet_updated"
+}
+```
+
+Sometimes, users need to get IP addresses on a subnet. Terraform built-in functions can be used to get IP addresses from `subnet`. 
+The following example returns first IP address in the subnet `test`:
+```hcl
+resource "softlayer_subnet" "test" {
+  type = "Static"
+  private = false
+  ip_version = 4
+  capacity = 4
+  endpoint_ip="159.8.181.82"
+}
+
+# Use a built-in function cidrhost with index 0.
+output "first_ip_address" {
+  value = "${cidrhost(softlayer_subnet.test.subnet,0)}"
+}
+```
+
+##### Argument Reference
+
+The following arguments are supported:
+
+* `private` | *boolean*
+    * Set the network property of the subnet if it is public or private.
+    * **Required**
+* `type` | *string*
+    * Set the type of the subnet. Accepted values are Portable and Static.
+    * **Required**
+* `ip_version` | *int*
+    * Set the IP version of the subnet. Accepted values are 4 and 6.
+    * *Default*: true
+    * **Optional**
+* `capacity` | *int*
+    * Set the size of the subnet.
+    * Accepted values for a public portable IPv4 subnet are 4, 8, 16, and 32.
+    * Accepted values for a private portable IPv4 subnet are 4, 8, 16, 32, and 64.
+    * Accepted values for a public static IPv4 subnet are 1, 2, 4, 8, 16, and 32.
+    * Accepted value for a public portable IPv6 subnet is 64. /64 block is created and 2^64 IP addresses are provided.
+    * Accepted value for a public static IPv6 subnet is 64.  /64 block is created and 2^64 IP addresses are provided.
+    * **Required** 
+* `vlan_id` | *int*
+    * VLAN id for portable subnet. It should be configured when the subnet is a portable subnet. Both public VLAN ID and private VLAN ID can 
+    be configured. Accepted values can be found [here](https://control.softlayer.com/network/vlans). Click on the desired VLAN and note the 
+    ID on the resulting URL. Or, you can also [refer to a VLAN by name using a data source](https://github.com/softlayer/terraform-provider-softlayer/blob/master/docs/datasources/softlayer_vlan.md). 
+    * **Optional**
+* `endpoint_ip` | *string*
+    * Target primary IP address for static subnet. It should be configured when the subnet is a static subnet. Only public IP address can be 
+    configured as a `endpoint_ip`. It can be public IP address of virtual servers, bare metal servers, and netscaler VPXs. `static subnet` will 
+    be created on VLAN where `endpoint_ip` is located in.
+    * **Optional**
+* `notes` | *string*
+    * Set comments for the subnet.
+    * **Optional**
+
+##### Attributes Reference
+
+The following attributes are exported:
+
+* `id` - id of the subnet.
+* `subnet` - It rovides IP address/netmask format (ex. 10.10.10.10/28). It can be used to get an available IP address in `subnet`. 

softlayer/provider.go

@@ -79,6 +79,7 @@ func Provider() terraform.ResourceProvider {
 			"softlayer_file_storage":                resourceSoftLayerFileStorage(),
 			"softlayer_block_storage":               resourceSoftLayerBlockStorage(),
 			"softlayer_dns_secondary":               resourceSoftLayerDnsSecondary(),
+			"softlayer_subnet":                      resourceSoftLayerSubnet(),
 		},
 
 		ConfigureFunc: providerConfigure,