Stellar::Erb

A robust, safe, and feature-rich wrapper for ERB (Embedded Ruby) template rendering outside of Rails.

Stellar::Erb provides a sophisticated yet easy-to-use solution for working with ERB templates in Ruby applications. It offers enhanced error handling, clean backtraces, and a flexible API that makes template rendering both powerful and maintainable.

• Safe Template Rendering: Built-in protection against common template injection vulnerabilities
• Rich Error Context: Detailed error messages with line numbers and surrounding code context
• Flexible Variable Passing: Support for both global and per-render local variables
• String Template Support: Render ERB directly from strings in addition to files
• Reusable Views: Create view instances for efficient template reuse
• Minimal Dependencies: Works standalone without requiring Rails

Add to your Gemfile:

gem 'stellar-erb'

Or install directly:

$ gem install stellar-erb

# template.erb
<div class="greeting">
  <h1>Hello, <%= name %>!</h1>
  <% if show_date %>
    <p>Today is <%= Date.today %></p>
  <% end %>
</div>

# Ruby code
result = Stellar::Erb.render('template.erb', 
  name: 'John',
  show_date: true
)

template_string = <<~ERB 
  <ul class="items">
    <% items.each do |item| %>
      <li><%= item.name %> - $<%= item.price %></li>
    <% end %>
  </ul>
ERB

result = Stellar::Erb.render_string(template_string, 
  items: [
    OpenStruct.new(name: 'Widget', price: 9.99),
    OpenStruct.new(name: 'Gadget', price: 19.99)
  ]
)

# Create a reusable view instance
header = Stellar::Erb::View.new('partials/header.erb', 
  company: 'Acme Corp',
  logo_url: '/images/logo.png'
)

# Render with different page-specific variables
page1 = header.render(title: 'Home Page')
page2 = header.render(title: 'About Us')

begin
  result = Stellar::Erb::View.render('template.erb', user: current_user)
rescue Stellar::Erb::Error => e
  puts "Template Error: #{e.message}"
  
  # Show context around the error
  puts "\nError Context:"
  puts e.context_lines.join("\n")
  
  # Access original error details
  puts "Line Number: #{e.line_number}"
  puts "Template Path: #{e.template_path}"
end

# Setup development environment
bin/setup

# Run tests
rake test

# Run specific test file
ruby -Ilib:test test/stellar/erb/view_test.rb

# Generate documentation
yard doc

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Add tests for your changes
4. Make your changes
5. Ensure tests pass (rake test)
6. Commit your changes (git commit -am 'Add amazing feature')
7. Push to the branch (git push origin feature/amazing-feature)
8. Create a Pull Request

flowchart TD
    A[Fork Repository] --> B[Clone Locally]
    B --> C[Install Dependencies]
    C --> D[Run Tests]
    D --> E{Tests Pass?}
    E -->|Yes| F[Create Feature Branch]
    E -->|No| D
    F --> G[Make Changes]
    G --> H[Run Tests]
    H --> I{Tests Pass?}
    I -->|Yes| J[Submit PR]
    I -->|No| G

Released under the MIT License. See LICENSE for details.

• Documentation: RubyDoc
• Issues: GitHub Issues
• Discussions: GitHub Discussions

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