Rails 8.0 Credentials: The Ultimate Guide to Secure Configuration Management

In the ever-evolving landscape of web development, Ruby on Rails continues to prioritize security and developer experience.

The removal of config.read_encrypted_secrets in Rails 8.0 marks a significant shift in how applications handle sensitive configuration data.

This change reflects the framework's commitment to more robust, streamlined secret management and pushes developers towards a more secure and standardized approach to handling credentials.

Encrypted secrets have been a part of Rails for several years, providing a way to store sensitive information like API keys, database passwords, and other confidential configuration details.

However, the credentials system introduced in Rails 5.2 has proven to be a more flexible and secure alternative.

With Rails 8.0, the old encrypted secrets method is being phased out completely, making it crucial for developers to understand and implement the new approach.

Why Remove Encrypted Secrets and Adopt Credentials?

The migration from encrypted secrets to credentials is driven by several key considerations:

1. Enhanced Security

The credentials system provides a more robust encryption mechanism. Unlike the previous encrypted secrets approach, which used a single encryption key, the new system offers:

• More granular key management

• Better integration with environment-specific configurations

• Improved key rotation capabilities

2. Simplified Configuration

The credentials approach simplifies how developers manage sensitive information:

• Centralized credential management

• Easier integration with version control

• Clearer separation of environment-specific configurations

Old Encrypted Secrets Approach:

# config/secrets.yml.enc
# Entire secrets file encrypted
Rails.application.secrets.database_password

New Credentials Approach:

# config/credentials.yml.enc
# More structured and flexible
Rails.application.credentials.database[:password]

3. Better Developer Workflow

The credentials system provides a more intuitive workflow:

• Built-in editor for managing credentials

• Easier sharing across development teams

• More predictable configuration management

New Tools in Ruby on Rails 8 Dependent on Credentials

Rails 8.0 introduces several new features and tools that leverage the credentials system:

1. Environment-Specific Credentials

# config/credentials/development.yml.enc
# config/credentials/production.yml.enc
database:
  username: dev_user
  password: secure_dev_password

# Access credentials
Rails.application.credentials.database[:username]

2. Encrypted Credentials for External Services

# config/credentials.yml.enc
aws:
  access_key_id: your_access_key
  secret_access_key: your_secret_key

stripe:
  publishable_key: pk_test_your_key
  secret_key: sk_test_your_secret_key

# Accessing service credentials
Rails.application.credentials.aws[:access_key_id]
Rails.application.credentials.stripe[:secret_key]

3. Credentials Encryption Key Management

# In config/master.key (gitignored)
# Stores the encryption key for credentials

# Environment variable alternative
# Set RAILS_MASTER_KEY in production environments
ENV['RAILS_MASTER_KEY']

How to Transition

Step 1: Prepare Your Application

Before migrating, ensure you're running Rails 7.x and have the credentials system in place:

# Open credentials file
rails credentials:edit

# For environment-specific credentials
rails credentials:edit --environment development
rails credentials:edit --environment production

Step 2: Migrate Existing Secrets

# Old approach
Rails.application.secrets.database_password

# New approach
Rails.application.credentials.database[:password]

Step 3: Update Configuration Files

# config/application.rb
class Application < Rails::Application
  # Remove old secret_key_base configuration
  # config.secret_key_base will now be managed via credentials
end

Step 4: Update Deployment Configurations

For production environments, ensure you set the master key:

• Heroku: heroku config:set RAILS_MASTER_KEY=your_master_key

• Docker: Mount the config/master.key or set RAILS_MASTER_KEY

• Cloud Platforms: Use their secret management tools

Common Pitfalls to Avoid

• Do not commit config/master.key to version control

• Always use environment-specific credentials

• Rotate your encryption keys periodically

• Use different keys for different environments

Why Use or Not Use Figaro vs. Credentials in Rails 8

Pros of Using Figaro

1. Simplicity: Figaro provides a straightforward configuration approach with minimal setup.

2. Environment Variable Support: Easy integration with environment variables.

3. Backward Compatibility: Works well with older Rails versions.

Cons of Figaro Compared to Credentials

1. Less Native Integration: Unlike credentials, Figaro is a third-party gem.

2. Limited Encryption: Lacks the robust encryption mechanism of Rails credentials.

3. Maintenance Overhead: Requires additional gem management.

Comparison Table

Code Comparison:

Figaro Approach:

# Gemfile
gem 'figaro'

# config/application.yml
development:
  DATABASE_PASSWORD: dev_password

# Usage
Figaro.env.database_password

Rails Credentials Approach:

# config/credentials.yml.enc
database:
  password: secure_password

# Usage
Rails.application.credentials.database[:password]

Recommendation

For Rails 8.0 and newer applications, it's strongly recommended to use the native credentials system due to:

• Direct Rails integration

• Superior security features

• Long-term support

• No additional gem dependencies

Frequently Asked Questions (FAQs)

Q1: How do I edit credentials in Rails?

A: Use the built-in editor:

rails credentials:edit
# For specific environment
rails credentials:edit --environment development

Q2: What happens if I lose my master key?

A: You'll lose access to encrypted credentials. Always:

• Securely backup your master key

• Use environment-specific key management

• Have a key rotation strategy

Q3: Can I use different credentials for different environments?

A: Yes! Rails supports environment-specific credentials:

# config/credentials/development.yml.enc
# config/credentials/production.yml.enc
# config/credentials/test.yml.enc

Q4: How secure are Rails credentials?

A: Highly secure due to:

• AES-256-GCM encryption

• Secure key management

• No plain-text secrets in version control

• Environment-specific configurations

Q5: Can I use environment variables with credentials?

A: Yes, you can combine both:

# Credentials file
database:
  password: <%= ENV['DATABASE_PASSWORD'] %>

# Or in code
password = Rails.application.credentials.database[:password] || ENV['DATABASE_PASSWORD']

Q6: What's the best way to share credentials in a team?

A: Recommended approaches:

1. Use a secure secret management service

2. Share master key through secure channels

3. Use environment-specific credential files

4. Implement strict access controls

Q7: How do I migrate from encrypted secrets to credentials?

A: Migration steps:

1. Generate new credentials file

2. Manually transfer secrets

3. Update application code references

4. Remove old secrets.yml.enc

5. Test thoroughly in each environment

Q8: Are credentials only for sensitive information?

A: While primarily for sensitive data, you can use credentials for:

• API keys

• Database configurations

• External service credentials

• Environment-specific settings

Pro Tip: Only store truly sensitive information in credentials. Use environment variables or configuration files for less critical settings.

Conclusion

The removal of config.read_encrypted_secrets in Rails 8.0 is more than just a technical change—it's a strategic move towards more secure, manageable, and developer-friendly configuration management.

By adopting the credentials system, developers gain:

• Enhanced security

• Better configuration management

• More flexible secret handling

• Improved team collaboration

While the transition requires some effort, the long-term benefits of the new credentials system far outweigh the initial migration challenges.

Rails continues to demonstrate its commitment to providing developers with tools that prioritize both security and developer experience.

Recommendation: Start planning your migration to the credentials system today. Update your applications gradually, test thoroughly, and embrace the more robust secret management approach in Rails 8.0.