Merge pull request #1632 from hashicorp/f-generate-sg-names

unique identifier helper for resources / generate AWS security group names

builtin/providers/aws/resource_aws_launch_configuration.go

@@ -364,16 +364,13 @@ func resourceAwsLaunchConfigurationCreate(d *schema.ResourceData, meta interface
  createLaunchConfigurationOpts.BlockDeviceMappings = blockDevices
  }
 
- var id string
+ var lcName string
  if v, ok := d.GetOk("name"); ok {
- id = v.(string)
+ lcName = v.(string)
  } else {
- hash := sha1.Sum([]byte(fmt.Sprintf("%#v", createLaunchConfigurationOpts)))
- configName := fmt.Sprintf("terraform-%s", base64.URLEncoding.EncodeToString(hash[:]))
- log.Printf("[DEBUG] Computed Launch config name: %s", configName)
- id = configName
+ lcName = resource.UniqueId()
  }
- createLaunchConfigurationOpts.LaunchConfigurationName = aws.String(id)
+ createLaunchConfigurationOpts.LaunchConfigurationName = aws.String(lcName)
 
  log.Printf(
  "[DEBUG] autoscaling create launch configuration: %#v", createLaunchConfigurationOpts)
@@ -382,7 +379,7 @@ func resourceAwsLaunchConfigurationCreate(d *schema.ResourceData, meta interface
  return fmt.Errorf("Error creating launch configuration: %s", err)
  }
 
- d.SetId(id)
+ d.SetId(lcName)
  log.Printf("[INFO] launch configuration ID: %s", d.Id())
 
  // We put a Retry here since sometimes eventual consistency bites

builtin/providers/aws/resource_aws_security_group.go

@@ -24,13 +24,15 @@ func resourceAwsSecurityGroup() *schema.Resource {
  Schema: map[string]*schema.Schema{
  "name": &schema.Schema{
  Type: schema.TypeString,
- Required: true,
+ Optional: true,
+ Computed: true,
  ForceNew: true,
  },
 
  "description": &schema.Schema{
  Type: schema.TypeString,
- Required: true,
+ Optional: true,
+ Default: "Managed by Terraform",
  },
 
  "vpc_id": &schema.Schema{
@@ -144,9 +146,7 @@ func resourceAwsSecurityGroup() *schema.Resource {
 func resourceAwsSecurityGroupCreate(d *schema.ResourceData, meta interface{}) error {
  conn := meta.(*AWSClient).ec2conn
 
- securityGroupOpts := &ec2.CreateSecurityGroupInput{
- GroupName: aws.String(d.Get("name").(string)),
- }
+ securityGroupOpts := &ec2.CreateSecurityGroupInput{}
 
  if v := d.Get("vpc_id"); v != nil {
  securityGroupOpts.VPCID = aws.String(v.(string))
@@ -156,6 +156,14 @@ func resourceAwsSecurityGroupCreate(d *schema.ResourceData, meta interface{}) er
  securityGroupOpts.Description = aws.String(v.(string))
  }
 
+ var groupName string
+ if v, ok := d.GetOk("name"); ok {
+ groupName = v.(string)
+ } else {
+ groupName = resource.UniqueId()
+ }
+ securityGroupOpts.GroupName = aws.String(groupName)
+
  log.Printf(
  "[DEBUG] Security Group create configuration: %#v", securityGroupOpts)
  createResp, err := conn.CreateSecurityGroup(securityGroupOpts)

builtin/providers/aws/resource_aws_security_group_test.go

@@ -3,6 +3,7 @@ package aws
 import (
  "fmt"
  "reflect"
+ "strings"
  "testing"
 
  "github.com/awslabs/aws-sdk-go/aws"
@@ -184,6 +185,35 @@ func TestAccAWSSecurityGroup_Change(t *testing.T) {
  })
 }
 
+func TestAccAWSSecurityGroup_generatedName(t *testing.T) {
+ var group ec2.SecurityGroup
+
+ resource.Test(t, resource.TestCase{
+ PreCheck: func() { testAccPreCheck(t) },
+ Providers: testAccProviders,
+ CheckDestroy: testAccCheckAWSSecurityGroupDestroy,
+ Steps: []resource.TestStep{
+ resource.TestStep{
+ Config: testAccAWSSecurityGroupConfig_generatedName,
+ Check: resource.ComposeTestCheckFunc(
+ testAccCheckAWSSecurityGroupExists("aws_security_group.web", &group),
+ resource.TestCheckResourceAttr(
+ "aws_security_group.web", "description", "Managed by Terraform"),
+ func(s *terraform.State) error {
+ if group.GroupName == nil {
+ return fmt.Errorf("bad: No SG name")
+ }
+ if !strings.HasPrefix(*group.GroupName, "terraform-") {
+ return fmt.Errorf("No terraform- prefix: %s", *group.GroupName)
+ }
+ return nil
+ },
+ ),
+ },
+ },
+ })
+}
+
 func testAccCheckAWSSecurityGroupDestroy(s *terraform.State) error {
  conn := testAccProvider.Meta().(*AWSClient).ec2conn
 
@@ -518,3 +548,18 @@ resource "aws_security_group" "foo" {
  }
 }
 `
+
+const testAccAWSSecurityGroupConfig_generatedName = `
+resource "aws_security_group" "web" {
+ ingress {
+ protocol = "tcp"
+ from_port = 80
+ to_port = 8000
+ cidr_blocks = ["10.0.0.0/8"]
+ }
+
+ tags {
+ Name = "tf-acc-test"
+ }
+}
+`

helper/resource/id.go

@@ -0,0 +1,41 @@
+package resource
+
+import (
+ "crypto/rand"
+ "encoding/base32"
+ "fmt"
+ "strings"
+)
+
+const UniqueIdPrefix = `terraform-`
+
+// Helper for a resource to generate a unique identifier
+//
+// This uses a simple RFC 4122 v4 UUID with some basic cosmetic filters
+// applied (base32, remove padding, downcase) to make visually distinguishing
+// identifiers easier.
+func UniqueId() string {
+ return fmt.Sprintf("%s%s", UniqueIdPrefix,
+ strings.ToLower(
+ strings.Replace(
+ base32.StdEncoding.EncodeToString(uuidV4()),
+ "=", "", -1)))
+}
+
+func uuidV4() []byte {
+ var uuid [16]byte
+
+ // Set all the other bits to randomly (or pseudo-randomly) chosen
+ // values.
+ rand.Read(uuid[:])
+
+ // Set the two most significant bits (bits 6 and 7) of the
+ // clock_seq_hi_and_reserved to zero and one, respectively.
+ uuid[8] = (uuid[8] | 0x80) & 0x8f
+
+ // Set the four most significant bits (bits 12 through 15) of the
+ // time_hi_and_version field to the 4-bit version number from Section 4.1.3.
+ uuid[6] = (uuid[6] | 0x40) & 0x4f
+
+ return uuid[:]
+}

helper/resource/id_test.go

@@ -0,0 +1,25 @@
+package resource
+
+import (
+ "strings"
+ "testing"
+)
+
+func TestUniqueId(t *testing.T) {
+ iterations := 10000
+ ids := make(map[string]struct{})
+ var id string
+ for i := 0; i < iterations; i++ {
+ id = UniqueId()
+
+ if _, ok := ids[id]; ok {
+ t.Fatalf("Got duplicated id! %s", id)
+ }
+
+ if !strings.HasPrefix(id, "terraform-") {
+ t.Fatalf("Unique ID didn't have terraform- prefix! %s", id)
+ }
+
+ ids[id] = struct{}{}
+ }
+}