Get AWS::StackName without the generated random hash - amazon-web-services

Question

How can one get the AWS::StackName without the random generate part?
I create a stack: aws cloudformation create-stack --stack-name test
The stack name returned when evaluated using AWS:StackName will included a random generated part, e.g. test-KB0IKRIHP9PH
What I really want returned is the parameter without the generated part, in this case test,
omitting -KB0IKRIHP9PH
My use case for this is, when my containers startup, they need to get database
credential from a pre created named secret. With the random part in place the service all fail to start initially until the secrets are created.
In the code below I assign the StackName to an environment variable.
TaskDefinition:
Type: AWS::ECS::TaskDefinition
Properties:
ContainerDefinitions:
- Name: website-service
Environment:
- Name: ENVIRONMENT_VAR
Value: !Join ["", ["CF_", {"Ref": "AWS::StackName"}]]
Here is an update as requested, to show how I create the stack. I am using a MakeFile...
create-test: s3
#ip_address=$$(dig #resolver1.opendns.com ANY myip.opendns.com +short); \
read -s -p "Enter DB Root Password: " pswd; \
[[ -z $$pswd ]] && exit 1 || \
aws cloudformation create-stack \
--capabilities CAPABILITY_IAM CAPABILITY_NAMED_IAM \
--stack-name test \
--template-body file://master.yaml \
--parameters ParameterKey=DBRootPassword,ParameterValue=$$pswd \
ParameterKey=DBHostAccessCidr,ParameterValue=$$ip_address/32

Answer 1

I test this with a simple template:
AWSTemplateFormatVersion: 2010-09-09
Resources:
Bucket:
Type: AWS::S3::Bucket
Outputs:
Stack:
Value: !Sub ${AWS::StackName}
The Stack output variable exactly matched the name of the stack that I created. There were no random characters.
I launched the stack via the console.

Answer 2

If AWS::StackName is in the form of test-KB0IKRIHP9PH, then you can get test and perform the Join as follows:
Environment:
- Name: ENVIRONMENT_VAR
Value: !Join ["", ["CD_", !Select [0, !Split ['-', !Ref "AWS::StackName"] ] ] ]

Answer 3

Nested Stack Names contain a random hash.
To overcome the problem, pass the AWS::StackName as a parameter to the nested stack, from the root/master stack.
In the example below, the AWS::StackName is passed as a parameter.
master.yaml
Resources:
S3:
Type: AWS::CloudFormation::Stack
Properties:
TemplateURL: https://s3-ap-southeast-2.amazonaws.com/...s3.yaml
Parameters:
ParamStackName: !Ref AWS::StackName
s3.yaml Notice: !Ref AWS::StackName while nested, will include a random hash.
Parameters:
ParamStackName:
Type: String
Resources:
MyS3:
Type: AWS::S3::Bucket
Properties:
# Using !Ref AWS::StackName will include the random hash
BucketName: !Ref ParamStackName