Concepts
Accessing application configuration data is a critical part of cloud application development and operations, as it allows you to manage your application’s settings and secrets efficiently and securely. AWS offers several services for this purpose, and understanding their use and applicability is essential for the AWS Certified Developer – Associate Exam (DVA-C02). The following sections will explore three of these services: AWS AppConfig, AWS Secrets Manager, and AWS Systems Manager Parameter Store.
AWS AppConfig
AWS AppConfig is a feature of AWS Systems Manager that allows developers to safely manage, access, and quickly roll out changes to configurations and features in applications running on AWS infrastructure.
How to Access Configuration Data with AWS AppConfig:
- Create a Configuration Profile – Define configurations for your applications within AppConfig.
- Deploy the Configuration – Using AppConfig’s deployment strategies, safely roll out changes to a subset of your instances or all at once.
- Access the Configuration – Your application can retrieve the latest configuration data using the AWS SDK or CLI.
Example:
import boto3
appconfig_client = boto3.client(‘appconfig’)
# Retrieve the configuration data
configuration = appconfig_client.get_configuration(
Application=’YourAppId’,
Environment=’YourEnvironmentName’,
Configuration=’YourConfigProfile’,
ClientId=’YourClientId’
)
# Use the configuration data in your application
config_data = configuration[‘Content’].read()
AWS Secrets Manager
AWS Secrets Manager helps you protect access to your applications, services, and IT resources without the upfront investment and on-going maintenance costs of operating your own infrastructure.
How to Access Secrets with AWS Secrets Manager:
- Store Secrets – Store database credentials, API keys, or other secrets within the Secrets Manager.
- Retrieve Secrets – Access these secrets programmatically using the AWS SDK in your application.
- Rotate Secrets – Automatically rotate the secrets without making changes to your applications.
Example:
import boto3
import json
secrets_client = boto3.client(‘secretsmanager’)
# Retrieve secret value
get_secret_value_response = secrets_client.get_secret_value(
SecretId=’YourSecretId’
)
# Parse and use the secrets
if ‘SecretString’ in get_secret_value_response:
secret = get_secret_value_response[‘SecretString’]
secret_dict = json.loads(secret)
# Example usage: the secret value for ‘username’
username = secret_dict[‘username’]
AWS Systems Manager Parameter Store
The AWS Systems Manager Parameter Store provides secure, hierarchical storage for configuration data management and secrets management.
How to Access Parameters with Parameter Store:
- Store Data – Securely store data, whether plain-text data like database strings, or secrets such as passwords, encrypted through KMS.
- Retrieve Data – Use the AWS SDK or CLI to programmatically access these parameters.
- Hierarchical Storage – Organize and manage parameters with hierarchy (path) so that configurations can be managed at varying levels of complexity.
Example:
import boto3
ssm_client = boto3.client(‘ssm’)
# Retrieve parameter value
parameter = ssm_client.get_parameter(
Name=’/path/to/your/parameter’,
WithDecryption=True # Set to True to retrieve secret data
)
# Access the parameter value
parameter_value = parameter[‘Parameter’][‘Value’]
Comparison of AppConfig, Secrets Manager, and Parameter Store
| Feature | AWS AppConfig | AWS Secrets Manager | AWS Systems Manager Parameter Store |
|---|---|---|---|
| Configurations | Designed for feature flags and settings | Designed for secret materials like credentials, tokens | Supports both configurations and secrets |
| Encryption | Securely stores with AWS KMS encryption | Securely stores secrets, supports automatic rotations | Secure storage with optional KMS encryption |
| Hierarchy | Supports environments and configurations | Flat structure without hierarchy | Supports hierarchical storage of parameters |
| Versioning | Supports versioning of configurations | Supports versioning of secrets | Supports versioning of parameters |
| Direct AWS Integration | Directly integrates with applications using the AppConfig client/runtime | Accessible via AWS SDKs, CLI, and console | Accessible via AWS SDKs, CLI, and console |
| Pricing | Charged per number of hosted configurations and deployments | Charged based on number of secrets and API calls | Charged based on number of parameters stored and API calls |
In conclusion, AWS AppConfig is optimal for managing application configurations and feature flags, AWS Secrets Manager for managing and rotating secrets, and AWS Systems Manager Parameter Store for a mix of hierarchical configurations and secrets. When preparing for the DVA-C02 exam, it’s essential to understand how to access and manage application configurations and secrets on AWS, as well as the use-cases and benefits of each service.
Answer the Questions in Comment Section
True or False: AWS AppConfig supports the deployment of configurations across applications hosted on both, AWS and on-premises environments.
- (A) True
- (B) False
Answer: A
Explanation: AWS AppConfig can indeed be used to deploy configurations across applications hosted on AWS as well as those hosted on-premises.
Which AWS service is primarily used for storing and managing secrets?
- (A) AWS AppConfig
- (B) AWS Parameter Store
- (C) AWS Secrets Manager
- (D) AWS CloudFormation
Answer: C
Explanation: AWS Secrets Manager is specifically designed for storing, managing, and retrieving secrets.
Which AWS service allows you to store, manage, and retrieve configuration parameters and secrets for your applications at scale?
- (A) AWS Elastic Beanstalk
- (B) AWS Parameter Store
- (C) AWS CodeDeploy
- (D) AWS Lambda
Answer: B
Explanation: AWS Systems Manager Parameter Store (often referred to as AWS Parameter Store) provides the capabilities to store, manage, and retrieve configuration parameters and secrets.
True or False: AWS Systems Manager Parameter Store automatically encrypts the stored parameters using AWS Key Management Service (KMS).
- (A) True
- (B) False
Answer: B
Explanation: AWS Parameter Store supports both plain text and encrypted parameters. For encrypted parameters, encryption must be specified, and KMS can be used for this purpose.
When should you use AWS AppConfig instead of AWS Secrets Manager?
- (A) When managing secrets like database credentials
- (B) When managing application parameters that do not contain secrets
- (C) When you need automated rotation for secrets
- (D) When you require secret storage with built-in auditing
Answer: B
Explanation: AWS AppConfig is better suited for managing application parameters that aren’t secrets, while AWS Secrets Manager is designed for handling actual secrets like credentials.
True or False: With AWS AppConfig, you can validate your configuration data against a schema before deploying it to your application.
- (A) True
- (B) False
Answer: A
Explanation: AWS AppConfig allows you to validate your configuration data against a schema or a set of Lambda functions before deployment.
Which of the following features are available in AWS Parameter Store? (Select two)
- (A) Automated secrets rotation
- (B) Integration with AWS Identity and Access Management (IAM)
- (C) Real-time configuration updates
- (D) Hierarchical organization of parameters
Answer: B, D
Explanation: AWS Parameter Store integrates with IAM for access control and allows hierarchical organization of parameters. Automated secrets rotation is a feature of AWS Secrets Manager.
What is the primary use of AWS AppConfig?
- (A) Deploying infrastructure as code
- (B) Continuous deployment of application code
- (C) Managing application configurations during runtime
- (D) Automated build and test for application code
Answer: C
Explanation: AWS AppConfig is designed to enable developers to manage and deploy application configurations during runtime without affecting performance.
True or False: AWS AppConfig is suitable for storing sensitive information like database passwords.
- (A) True
- (B) False
Answer: B
Explanation: AWS AppConfig isn’t suited for storing sensitive information. Sensitive information should be stored using AWS Secrets Manager.
In AWS Systems Manager, what is “Parameter Store” primarily used for?
- (A) Managing machine images (AMIs)
- (B) Storing configuration data and secrets
- (C) Defining infrastructure as code
- (D) Monitoring and logging
Answer: B
Explanation: Parameter Store, a service within AWS Systems Manager, is used for storing and managing configuration data and secrets.
Which AWS service is serverless and allows you to manage application configuration and secrets without provisioning infrastructure?
- (A) AWS Lambda
- (B) AWS AppConfig
- (C) AWS Secrets Manager
- (D) Both B and C
Answer: D
Explanation: Both AWS AppConfig and AWS Secrets Manager are serverless offerings allowing the management of configuration and secrets without managing infrastructure.
True or False: AWS AppConfig can perform a gradual deployment of configuration changes across a set of targets to mitigate risks.
- (A) True
- (B) False
Answer: A
Explanation: AWS AppConfig supports a gradual rollout of configuration changes, which can be used to mitigate risks associated with deploying new configurations.
Great post! I’ve been using AWS Secrets Manager for managing sensitive information. It’s really easy to integrate with Lambda.
AWS Parameter Store all the way! It’s perfect for storing configuration data that doesn’t change frequently.
Does anyone have experience using AWS AppConfig? I’m curious about its benefits over other configuration management tools.
I appreciate the blog post! Really helped me understand the differences.
I think the cost of Secrets Manager can get high if you store a lot of secrets. Parameter Store might be more cost-effective.
Thanks for the post! Just what I needed for my exam prep.
Anyone tried integrating these services with CI/CD pipelines?
Loved the article! Thanks for sharing your knowledge.