Merge pull request #17 from gerred/add-uuidv4

Add UUIDv4 function

README.md

@@ -106,6 +106,7 @@ parse, it returns the time unaltered. See `time.ParseDuration` for info on durat
 - replace: Replace an old with a new in a string: `$name | replace " " "-"`
 - plural: Choose singular or plural based on length: `len $fish | plural
   "one anchovy" "many anchovies"`
+- uuidv4: Generate a UUID v4 string
 
 ### String Slice Functions:
 

functions.go

@@ -181,6 +181,7 @@ import (
 	"time"
 
 	util "github.com/aokoli/goutils"
+	uuid "github.com/satori/go.uuid"
 )
 
 // Produce the function map.
@@ -239,6 +240,7 @@ var nonhermeticFunctions = []string{
 	"randAlpha",
 	"randAscii",
 	"randNumeric",
+	"uuidv4",
 
 	// OS
 	"env",
@@ -365,6 +367,9 @@ var genericMap = map[string]interface{}{
 
 	// Crypto:
 	"genPrivateKey": generatePrivateKey,
+
+	// UUIDs:
+	"uuidv4": uuidv4,
 }
 
 func split(sep, orig string) map[string]string {
@@ -795,3 +800,8 @@ func untilStep(start, stop, step int) []int {
 	}
 	return v
 }
+
+// uuidv4 provides a safe and secure UUID v4 implementation
+func uuidv4() string {
+	return fmt.Sprintf("%s", uuid.NewV4())
+}

functions_test.go

@@ -529,6 +529,27 @@ func TestGenPrivateKey(t *testing.T) {
 	}
 }
 
+func TestUUIDGeneration(t *testing.T) {
+	tpl := `{{uuidv4}}`
+	out, err := runRaw(tpl, nil)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if len(out) != 36 {
+		t.Error("Expected UUID of length 36")
+	}
+
+	out2, err := runRaw(tpl, nil)
+	if err != nil {
+		t.Error(err)
+	}
+
+	if out == out2 {
+		t.Error("Expected subsequent UUID generations to be different")
+	}
+}
+
 func runt(tpl, expect string) error {
 	return runtv(tpl, expect, map[string]string{})
 }

glide.yaml

@@ -1,3 +1,5 @@
 package: github.com/Masterminds/sprig
 import:
 - package: github.com/aokoli/goutils
+- package: github.com/satori/go.uuid
+  version: ^1.1.0