get the cloudformation stack output by outputkey

cloudformation_stack_output.sh

#!/usr/bin/env bash
set -euo pipefail
IFS=$'\n\t'

key="ServiceEndpointWebsocket"
stack_name="sh-ws-demo-backend-dev"

aws cloudformation describe-stacks --stack-name "${stack_name}" \
    --query "Stacks[0].Outputs[?OutputKey=='${key}'].OutputValue" \
    --output text

# {
#     "Stacks": [
#         {
#             "StackId": "arn:aws:cloudformation:us-east-2:668805947503:stack/sh-ws-demo-backend-dev/81cbddb0-e3c4-11ed-aff0-02a190a45eed",
#             "StackName": "sh-ws-demo-backend-dev",
#             "ChangeSetId": "arn:aws:cloudformation:us-east-2:668805947503:changeSet/sh-ws-demo-backend-dev-change-set/55c1d391-757c-48c0-92f4-63c9d8844cc0",
#             "Description": "The AWS CloudFormation template for this Serverless application",
#             "CreationTime": "2023-04-25T23:54:25.010000+00:00",
#             "LastUpdatedTime": "2023-04-27T22:02:47.514000+00:00",
#             "RollbackConfiguration": {},
#             "StackStatus": "UPDATE_COMPLETE",
#             "DisableRollback": false,
#             "NotificationARNs": [],
#             "Capabilities": [
#                 "CAPABILITY_IAM",
#                 "CAPABILITY_NAMED_IAM"
#             ],
#             "Outputs": [
#                 {
#                     "OutputKey": "ConnectionManagerLambdaFunctionQualifiedArn",
#                     "OutputValue": "arn:aws:lambda:us-east-2:668805947503:function:sh-ws-demo-backend-dev-connectionManager:29",
#                     "Description": "Current Lambda function version",
#                     "ExportName": "sls-sh-ws-demo-backend-dev-ConnectionManagerLambdaFunctionQualifiedArn"
#                 },
#                 {
#                     "OutputKey": "SnsUnderscorerouterLambdaFunctionQualifiedArn",
#                     "OutputValue": "arn:aws:lambda:us-east-2:668805947503:function:sh-ws-demo-backend-dev-sns_router:9",
#                     "Description": "Current Lambda function version",
#                     "ExportName": "sls-sh-ws-demo-backend-dev-SnsUnderscorerouterLambdaFunctionQualifiedArn"
#                 },
#                 {
#                     "OutputKey": "DefaultMessageLambdaFunctionQualifiedArn",
#                     "OutputValue": "arn:aws:lambda:us-east-2:668805947503:function:sh-ws-demo-backend-dev-defaultMessage:29",
#                     "Description": "Current Lambda function version",
#                     "ExportName": "sls-sh-ws-demo-backend-dev-DefaultMessageLambdaFunctionQualifiedArn"
#                 },
#                 {
#                     "OutputKey": "ServiceEndpointWebsocket",
#                     "OutputValue": "wss://xbbv6yjs83.execute-api.us-east-2.amazonaws.com/dev",
#                     "Description": "URL of the service endpoint",
#                     "ExportName": "sls-sh-ws-demo-backend-dev-ServiceEndpointWebsocket"
#                 },
#                 {
#                     "OutputKey": "ServerlessDeploymentBucketName",
#                     "OutputValue": "sh-ws-demo-backend-dev-serverlessdeploymentbucket-soectn0wn1vo",
#                     "ExportName": "sls-sh-ws-demo-backend-dev-ServerlessDeploymentBucketName"
#                 }
#             ],
#             "Tags": [
#                 {
#                     "Key": "STAGE",
#                     "Value": "dev"
#                 }
#             ],
#             "EnableTerminationProtection": false,
#             "DriftInformation": {
#                 "StackDriftStatus": "NOT_CHECKED"
#             }
#         }
#     ]
# }
#