Dependencies and Configuration

Relevant source files

• CHANGELOG.md
• README.md
• lib/solid/process/class_methods.rb
• lib/solid/process/config.rb
• lib/solid/process/version.rb
• test/solid/process/config_test.rb
• test/solid/process/dependencies/assignment_alias_test.rb
• test/solid/process/dependencies/result_test.rb
• test/solid/process/result_test.rb

This document covers the dependency injection system and global configuration mechanisms in the Solid::Process framework. It explains how to configure default base classes for inputs and dependencies, how to define and inject dependencies into processes, and how the framework validates dependency interfaces.

For information about input validation and data modeling patterns, see Input and Data Modeling. For details about the core process execution flow, see Solid::Process - The Core Abstraction.

Configuration System

The Solid::Process framework provides a global configuration system through the Solid::Process::Config class that allows customization of default base classes for inputs and dependencies.

Global Configuration Structure

Sources: lib/solid/process/config.rb1-35 lib/solid/process/class_methods.rb1-42

The configuration system uses a singleton pattern where Config.instance provides the global configuration object. The SolidModel lambda validates that configured classes include the Solid::Model module.

Configuration Methods

The framework provides several methods for accessing and modifying configuration:

Method	Purpose	Example Usage
Solid::Process.config	Access current configuration	Solid::Process.config.input_class
Solid::Process.configuration	Configure with block	`Solid::Process.configuration {
Solid::Process.configure	Alias for configuration	Same as above

Sources: test/solid/process/config_test.rb14-42

Dependency Injection System

The dependency injection system allows processes to declare external dependencies that can be validated and customized for different environments.

Dependency Definition Patterns

Sources: lib/solid/process/class_methods.rb11-37

Dependencies are defined using either the dependencies method with a block, or by assigning a pre-existing class using dependencies=. The framework automatically creates a Dependencies constant within the process class.

Dependency Interface Validation

Dependencies can validate their own interfaces to ensure they provide required methods:

Sources: test/support/040_user_creation_with_dependencies.rb7-12

Repository Pattern Example

The framework commonly uses the repository pattern for database dependencies:

Component	Responsibility	Implementation
dependencies.repository	Data access interface	Default: ::User
Interface validation	Ensures required methods	respond_to?(:create!), respond_to?(:exists?)
Default values	Fallback implementations	default: ::User

Sources: test/support/040_user_creation_with_dependencies.rb4-13

Class Method API

The ClassMethods module provides the DSL for defining inputs and dependencies within process classes.

Input Definition Flow

Sources: lib/solid/process/class_methods.rb11-20

Dependencies Definition Flow

Sources: lib/solid/process/class_methods.rb28-36

Configuration Customization

Custom Base Classes

You can configure custom base classes for inputs and dependencies globally:

Sources: test/solid/process/config_test.rb44-96

Assignment vs Block Definition

The framework supports two patterns for defining dependencies and inputs:

Pattern	Usage	When to Use
Class Assignment	self.deps = MyDepsClass	Pre-existing, reusable dependency classes
Block Definition	deps { attribute :repo }	Process-specific, inline definitions

Sources: test/solid/process/dependencies/assignment_alias_test.rb10-23

Alias Methods

The framework provides convenient aliases for common operations:

Primary Method	Alias	Purpose
dependencies	deps	Shorter syntax for dependency access
dependencies=	deps=	Shorter syntax for dependency assignment
dependencies_class	deps_class	Configuration alias

Sources: lib/solid/process/class_methods.rb39-40 lib/solid/process/config.rb26-27

Practical Usage Patterns

With Dependencies vs Without Dependencies

The framework supports both patterns - processes with external dependencies and self-contained processes:

Sources: test/support/040_user_creation_with_dependencies.rb1-61 test/support/030_user_creation_without_deps.rb1-50

Validation and Error Handling

Dependencies support the full validation framework available to Solid::Input:

Validation Type	Example	Purpose
Presence	validates :repository, presence: true	Ensure required dependencies
Custom validation	validate :repository_interface	Interface compliance checking
Format validation	validates :api_key, format: {...}	String format requirements

Sources: test/support/040_user_creation_with_dependencies.rb7-12