Common Issues in Hanami

Hanami-related problems often arise due to incorrect route configurations, missing templates, ORM misconfigurations, dependency version conflicts, or improper production settings. Identifying and resolving these challenges improves application reliability and performance.

Common Symptoms

  • Routes returning 404 errors despite correct definitions.
  • Views not rendering or missing template errors.
  • Database connection failures or migrations not applying.
  • Gem dependency conflicts preventing the application from running.
  • Deployment failures on cloud platforms or Docker environments.

Root Causes and Architectural Implications

1. Routing and Controller Issues

Incorrectly defined routes, missing controller actions, or improper HTTP method usage can cause 404 errors.

# Check defined routes
bundle exec hanami routes

2. View Rendering Problems

Incorrect template file names, missing partials, or rendering engine misconfigurations can cause views to fail.

# Verify template file location
app/views/home/index.html.erb

3. Database Connectivity Issues

Misconfigured database settings, incorrect environment variables, or unexecuted migrations can prevent database access.

# Check database configuration
cat config/database.yml

4. Dependency and Gem Conflicts

Incompatible gem versions or missing dependencies can cause the application to fail during startup.

# Resolve dependency conflicts
bundle install --full-index

5. Deployment and Environment Configuration Failures

Incorrect environment variables, missing assets, or improper server configurations can cause deployment issues.

# Precompile assets before deployment
bundle exec hanami assets precompile

Step-by-Step Troubleshooting Guide

Step 1: Fix Routing and Controller Issues

Ensure routes are correctly defined and match expected controller actions.

# Generate a route list to debug
bundle exec hanami routes

Step 2: Debug View Rendering Errors

Ensure correct view templates exist and match the expected naming conventions.

# Regenerate missing templates
bundle exec hanami generate view home#index

Step 3: Resolve Database Connection Failures

Ensure database credentials are correct and migrations are applied.

# Run pending migrations
bundle exec hanami db migrate

Step 4: Fix Dependency Conflicts

Resolve gem version conflicts by updating or reinstalling dependencies.

# Update all dependencies
bundle update

Step 5: Debug Deployment and Configuration Errors

Ensure all required environment variables are set and assets are compiled correctly.

# Set up production environment variables
export HANAMI_ENV=production

Conclusion

Optimizing Hanami applications requires resolving routing issues, ensuring view templates render correctly, fixing database connectivity, managing gem dependencies efficiently, and configuring deployment settings properly. By following these best practices, developers can maintain a reliable and scalable Ruby application.

FAQs

1. Why is my Hanami route returning a 404 error?

Check route definitions using `bundle exec hanami routes` and ensure the correct HTTP method is used.

2. How do I fix missing view templates?

Ensure the template file exists in the `app/views` directory and follows the correct naming conventions.

3. Why is my database connection failing?

Verify database credentials, check if the database is running, and apply pending migrations.

4. How do I resolve gem dependency conflicts?

Run `bundle update` to update gems and ensure version compatibility.

5. What should I check if my Hanami deployment fails?

Ensure environment variables are set, assets are precompiled, and the correct server configuration is used.