Troubleshooting AWS Proton

Learn to troubleshoot issues with AWS Proton.

Deployment errors that reference AWS CloudFormation dynamic parameters

If you see deployment errors that reference your CloudFormation dynamic variables, verify that they are Jinja escaped. These errors can be caused by Jinja misinterpretation of your dynamic variables. The CloudFormation dynamic parameter syntax is very similar the Jinja syntax you use with your AWS Proton parameters.

Example CloudFormation dynamic variable syntax:

'{{resolve:secretsmanager:MySecret:SecretString:password:EXAMPLE1-90ab-cdef-fedc-ba987EXAMPLE}}'.

Example AWS Proton parameter Jinja syntax:

'{{ service_instance.environment.outputs.env-outputs }}'.

To avoid these misinterpretation errors, Jinja escape your CloudFormation dynamic parameters as shown in the following examples.

This example is from the AWS CloudFormation User Guide. The AWS Secrets Manager secret-name and json-key segments can be used to retrieve the sign-in credentials stored in the secret.

MyRDSInstance:
  Type: AWS::RDS::DBInstance
  Properties:
    DBName: 'MyRDSInstance'
      AllocatedStorage: '20'
      DBInstanceClass: db.t2.micro
      Engine: mysql
      MasterUsername: '{{resolve:secretsmanager:MyRDSSecret:SecretString:username}}'
      MasterUserPassword: '{{resolve:secretsmanager:MyRDSSecret:SecretString:password}}'

To escape the CloudFormation dynamic parameters you can use two different methods:

• Enclose a block between {% raw %} and {% endraw %}:

  '{% raw %}'
  MyRDSInstance:
    Type: AWS::RDS::DBInstance
    Properties:
      DBName: 'MyRDSInstance'
        AllocatedStorage: '20'
        DBInstanceClass: db.t2.micro
        Engine: mysql
        MasterUsername: '{{resolve:secretsmanager:MyRDSSecret:SecretString:username}}'
        MasterUserPassword: '{{resolve:secretsmanager:MyRDSSecret:SecretString:password}}'
  '{% endraw %}'

• Enclose a parameter between "{{ }}":

  MyRDSInstance:
    Type: AWS::RDS::DBInstance
    Properties:
      DBName: 'MyRDSInstance'
        AllocatedStorage: '20'
        DBInstanceClass: db.t2.micro
        Engine: mysql
        MasterUsername: "{{ '{{resolve:secretsmanager:MyRDSSecret:SecretString:username}}' }}"
        MasterUserPassword: "{{ '{{resolve:secretsmanager:MyRDSSecret:SecretString:password}}' }}"
  

For information, see Jinja escaping.