resource: use regex replace to match the stack name for cloudformation

resource/stack.go

@@ -2,6 +2,7 @@ package resource
 
 import (
  "fmt"
+ "regexp"
  "strings"
  "time"
 
@@ -100,6 +101,9 @@ func (s Stack) CloudformationParametersType() ([]*cloudformation.Parameter, erro
  return params, nil
 }
 
+// CloudformationStackName returns the corresponding stack name to create in cloudformation.
+//
+// The name needs to match [a-zA-Z][-a-zA-Z0-9]*|arn:[-a-zA-Z0-9:/._+]*
 func (s Stack) CloudformationStackName() *string {
  // Replace:
  // - "/" with "-", "/" appears in the path
@@ -112,6 +116,16 @@ func (s Stack) CloudformationStackName() *string {
  name = name + "-" + s.Region
  }
 
+ // Stack name needs to start with [a-zA-Z]
+ // Remove leading characters that are not alphabetic
+ firstAlphaRegex := regexp.MustCompile(`^[^a-zA-Z]*`)
+ name = firstAlphaRegex.ReplaceAllString(name, "")
+
+ // Ensure the first character is alphabetic (already guaranteed by the previous step)
+ // Remove or replace all characters that do not match [-a-zA-Z0-9]
+ validCharsRegex := regexp.MustCompile(`[^-a-zA-Z0-9]+`)
+ name = validCharsRegex.ReplaceAllString(name, "-")
+
  return &name
 }
 

resource/stack_test.go

@@ -41,3 +41,40 @@ func setFields(s *Stack) {
  }
  }
 }
+
+func TestCloudformationStackName(t *testing.T) {
+ tests := []struct {
+ input Stack
+
+ want string
+ }{
+ {
+ input: Stack{
+ Name: "name",
+ Path: "path",
+ Region: "us-west-2",
+ },
+ want: "name-path-us-west-2",
+ },
+ {
+ input: Stack{
+ Path: "./path",
+ Region: "us-west-2",
+ },
+ want: "path-us-west-2",
+ },
+ {
+ input: Stack{
+ Name: "@danny",
+ Path: "./path",
+ Region: "us-west-2",
+ },
+ want: "danny---path-us-west-2",
+ },
+ }
+
+ for _, tc := range tests {
+ assert.Equal(t, tc.want, *tc.input.CloudformationStackName())
+ }
+
+}