drupal-expert

CRITICAL: Before writing ANY custom code, ALWAYS research existing solutions first.

When a developer asks you to implement functionality:

1. Ask the developer: "Have you checked drupal.org for existing contrib modules that solve this?"
2. Offer to research: "I can help search for existing solutions before we build custom code."
3. Only proceed with custom code after confirming no suitable contrib module exists.

How to Research Contrib Modules

Search on [drupal.org/project/project_module](https://www.drupal.org/project/project_module):

Evaluate module health by checking:

• Drupal 10/11 compatibility
• Security coverage (green shield icon)
• Last commit date (active maintenance?)
• Number of sites using it
• Issue queue responsiveness
• Whether it's covered by Drupal's security team

Ask these questions:

• Is there a well-maintained contrib module for this?
• Can an existing module be extended rather than building from scratch?
• Is there a Drupal Recipe (10.3+) that bundles this functionality?
• Would a patch to an existing module be better than custom code?

1. Follow Drupal Coding Standards

• PSR-4 autoloading for all classes in src/
• Use PHPCS with Drupal/DrupalPractice standards
• Proper docblock comments on all functions and classes
• Use t() for all user-facing strings with proper placeholders:

- @variable - sanitized text

- %variable - sanitized and emphasized

- :variable - URL (sanitized)

2. Use Dependency Injection

• Never use \Drupal::service() in classes - inject via constructor
• Define services in *.services.yml
• Use ContainerInjectionInterface for forms and controllers
• Use ContainerFactoryPluginInterface for plugins

```php

// WRONG - static service calls

class MyController {

public function content() {

$user = \Drupal::currentUser();

}

}

// CORRECT - dependency injection

class MyController implements ContainerInjectionInterface {

public function __construct(

protected AccountProxyInterface $currentUser,

) {}

public static function create(ContainerInterface $container) {

return new static(

$container->get('current_user'),

);

}

}

```

3. Hooks vs Event Subscribers

Both are valid in modern Drupal. Choose based on context:

Use OOP Hooks when:

• Altering Drupal core/contrib behavior
• Following core conventions
• Hook order (module weight) matters

Use Event Subscribers when:

• Integrating with third-party libraries (PSR-14)
• Building features that bundle multiple customizations
• Working with Commerce or similar event-heavy modules

```php

// OOP Hook (Drupal 11+)

#[Hook('form_alter')]

public function formAlter(&$form, FormStateInterface $form_state, $form_id): void {

// ...

}

// Event Subscriber

public static function getSubscribedEvents() {

return [

KernelEvents::REQUEST => ['onRequest', 100],

];

}

```

4. Security First

• Never trust user input - always sanitize
• Use parameterized database queries (never concatenate)
• Check access permissions properly
• Use #markup with Xss::filterAdmin() or #plain_text
• Review OWASP top 10 for Drupal-specific risks

Tests are not optional for production code.

Test Types (Choose Appropriately)

| Type | Base Class | Use When |

|------|------------|----------|

| Unit | UnitTestCase | Testing isolated logic, no Drupal dependencies |

| Kernel | KernelTestBase | Testing services, entities, with minimal Drupal |

| Functional | BrowserTestBase | Testing user workflows, page interactions |

| FunctionalJS | WebDriverTestBase | Testing JavaScript/AJAX functionality |

Test File Location

```

my_module/

└── tests/

└── src/

├── Unit/ # Fast, isolated tests

├── Kernel/ # Service/entity tests

└── Functional/ # Full browser tests

```

When to Write Each Type

• Unit tests: Pure PHP logic, utility functions, data transformations
• Kernel tests: Services, database queries, entity operations, hooks
• Functional tests: Forms, controllers, access control, user flows
• FunctionalJS tests: Dynamic forms, AJAX, JavaScript behaviors

Running Tests

```bash

# Run specific test

./vendor/bin/phpunit modules/custom/my_module/tests/src/Unit/MyTest.php

# Run all module tests

./vendor/bin/phpunit modules/custom/my_module

# Run with coverage

./vendor/bin/phpunit --coverage-html coverage modules/custom/my_module

```

```

my_module/

├── my_module.info.yml

├── my_module.module # Hooks only (keep thin)

├── my_module.services.yml # Service definitions

├── my_module.routing.yml # Routes

├── my_module.permissions.yml # Permissions

├── my_module.libraries.yml # CSS/JS libraries

├── config/

│ ├── install/ # Default config

│ ├── optional/ # Optional config (dependencies)

│ └── schema/ # Config schema (REQUIRED for custom config)

├── src/

│ ├── Controller/

│ ├── Form/

│ ├── Plugin/

│ │ ├── Block/

│ │ └── Field/

│ ├── Service/

│ ├── EventSubscriber/

│ └── Hook/ # OOP hooks (Drupal 11+)

├── templates/ # Twig templates

└── tests/

└── src/

├── Unit/

├── Kernel/

└── Functional/

```

Service Definition

```yaml

services:

my_module.my_service:

class: Drupal\my_module\Service\MyService

arguments: ['@entity_type.manager', '@current_user', '@logger.factory']

```

Route with Permission

```yaml

my_module.page:

path: '/my-page'

defaults:

_controller: '\Drupal\my_module\Controller\MyController::content'

_title: 'My Page'

requirements:

_permission: 'access content'

```

Plugin (Block Example)

```php

#[Block(

id: "my_block",

admin_label: new TranslatableMarkup("My Block"),

)]

class MyBlock extends BlockBase implements ContainerFactoryPluginInterface {

// Always use ContainerFactoryPluginInterface for DI in plugins

}

```

Config Schema (Required!)

```yaml

# config/schema/my_module.schema.yml

my_module.settings:

type: config_object

label: 'My Module settings'

mapping:

enabled:

type: boolean

label: 'Enabled'

limit:

type: integer

label: 'Limit'

```

Always use the database abstraction layer:

```php

// CORRECT - parameterized query

$query = $this->database->select('node', 'n');

$query->fields('n', ['nid', 'title']);

$query->condition('n.type', $type);

$query->range(0, 10);

$results = $query->execute();

// NEVER do this - SQL injection risk

$result = $this->database->query("SELECT * FROM node WHERE type = '$type'");

```

Always add cache metadata to render arrays:

```php

$build['content'] = [

'#markup' => $content,

'#cache' => [

'tags' => ['node_list', 'user:' . $uid],

'contexts' => ['user.permissions', 'url.query_args'],

'max-age' => 3600,

],

];

```

Cache Tag Conventions

• node:123 - specific node
• node_list - any node list
• user:456 - specific user
• config:my_module.settings - configuration

Before writing custom code, use Drush generators to scaffold boilerplate code.

Drush's code generation features follow Drupal best practices and coding standards, reducing errors and accelerating development. Always prefer CLI tools over manual file creation for standard Drupal structures.

Content Types and Fields

CRITICAL: Use CLI commands to create content types and fields instead of manual configuration or PHP code.

#### Create Content Types

```bash

# Interactive mode - Drush prompts for all details

drush generate content-entity

# Create via PHP eval (for scripts/automation)

drush php:eval "

\$type = \Drupal\node\Entity\NodeType::create([

'type' => 'article',

'name' => 'Article',

'description' => 'Articles with images and tags',

'new_revision' => TRUE,

'display_submitted' => TRUE,

'preview_mode' => 1,

]);

\$type->save();

echo 'Content type created.';

"

```

#### Create Fields

```bash

# Interactive mode (recommended for first-time use)

drush field:create

# Non-interactive mode with all parameters

drush field:create node article \

--field-name=field_subtitle \

--field-label="Subtitle" \

--field-type=string \

--field-widget=string_textfield \

--is-required=0 \

--cardinality=1

# Create a reference field

drush field:create node article \

--field-name=field_tags \

--field-label="Tags" \

--field-type=entity_reference \

--field-widget=entity_reference_autocomplete \

--cardinality=-1 \

--target-type=taxonomy_term

# Create an image field

drush field:create node article \

--field-name=field_image \

--field-label="Image" \

--field-type=image \

--field-widget=image_image \

--is-required=0 \

--cardinality=1

```

Common field types:

• string - Plain text
• string_long - Long text (textarea)
• text_long - Formatted text
• text_with_summary - Body field with summary
• integer - Whole numbers
• decimal - Decimal numbers
• boolean - Checkbox
• datetime - Date/time
• email - Email address
• link - URL
• image - Image upload
• file - File upload
• entity_reference - Reference to other entities
• list_string - Select list
• telephone - Phone number

Common field widgets:

• string_textfield - Single line text
• string_textarea - Multi-line text
• text_textarea - Formatted text area
• text_textarea_with_summary - Body with summary
• number - Number input
• checkbox - Single checkbox
• options_select - Select dropdown
• options_buttons - Radio buttons/checkboxes
• datetime_default - Date picker
• email_default - Email input
• link_default - URL input
• image_image - Image upload
• file_generic - File upload
• entity_reference_autocomplete - Autocomplete reference

#### Manage Fields

```bash

# List all fields on a content type

drush field:info node article

# List available field types

drush field:types

# List available field widgets

drush field:widgets

# List available field formatters

drush field:formatters

# Delete a field

drush field:delete node.article.field_subtitle

```

Generate Module Scaffolding

```bash

# Generate a complete module

drush generate module

# Prompts for: module name, description, package, dependencies

# Generate a controller

drush generate controller

# Prompts for: module, class name, route path, services to inject

# Generate a simple form

drush generate form-simple

# Creates form with submit/validation, route, and menu link

# Generate a config form

drush generate form-config

# Creates settings form with automatic config storage

# Generate a block plugin

drush generate plugin:block

# Creates block plugin with dependency injection support

# Generate a service

drush generate service

# Creates service class and services.yml entry

# Generate a hook implementation

drush generate hook

# Creates hook in .module file or OOP hook class (D11)

# Generate an event subscriber

drush generate event-subscriber

# Creates subscriber class and services.yml entry

```

Generate Entity Types

```bash

# Generate a custom content entity

drush generate entity:content

# Creates entity class, storage, access control, views integration

# Generate a config entity

drush generate entity:configuration

# Creates config entity with list builder and forms

```

Generate Common Patterns

```bash

# Generate a plugin (various types)

drush generate plugin:field:formatter

drush generate plugin:field:widget

drush generate plugin:field:type

drush generate plugin:block

drush generate plugin:condition

drush generate plugin:filter

# Generate a Drush command

drush generate drush:command-file

# Generate a test

drush generate test:unit

drush generate test:kernel

drush generate test:browser

```

Create Test Content

Use Devel Generate for test data instead of manual entry:

```bash

# Generate 50 nodes

drush devel-generate:content 50 --bundles=article,page --kill

# Generate taxonomy terms

drush devel-generate:terms 100 tags --kill

# Generate users

drush devel-generate:users 20

# Generate media entities

drush devel-generate:media 30 --bundles=image,document

```

Workflow Best Practices

1. Always start with generators:

```bash

# Create module structure first

drush generate module

# Then generate specific components

drush generate controller

drush generate form-config

drush generate service

```

2. Use field:create for all field additions:

```bash

# Never manually create field config files

# Use drush field:create instead

drush field:create node article --field-name=field_subtitle

```

3. Export configuration after CLI changes:

```bash

# After creating fields/content types via CLI

drush config:export -y

```

4. Document your scaffolding in README:

```markdown

This module was scaffolded with:

• drush generate module
• drush generate controller
• drush field:create node article --field-name=field_custom

```

Avoiding Common Mistakes

DON'T manually create:

• Content type config files (node.type.*.yml)
• Field config files (field.field..yml, field.storage..yml)
• View mode config (core.entity_view_display.*.yml)
• Form mode config (core.entity_form_display.*.yml)

DO use CLI commands:

• drush generate for code scaffolding
• drush field:create for fields
• drush php:eval for content types
• drush config:export to capture changes

Integration with DDEV/Docker

```bash

# When using DDEV

ddev drush generate module

ddev drush field:create node article

# When using Docker Compose

docker compose exec php drush generate module

docker compose exec php drush field:create node article

# When using DDEV with custom commands

ddev exec drush generate controller

```

Non-Interactive Mode for Automation and AI Agents

CRITICAL: Drush generators are interactive by default. Use these techniques to bypass prompts for automation, CI/CD pipelines, and AI-assisted development.

#### Method 1: --answers with JSON (Recommended)

Pass all answers as a JSON object. This is the most reliable method for complete automation:

```bash

# Generate a complete module non-interactively

drush generate module --answers='{

"name": "My Custom Module",

"machine_name": "my_custom_module",

"description": "A custom module for specific functionality",

"package": "Custom",

"dependencies": "",

"install_file": "no",

"libraries": "no",

"permissions": "no",

"event_subscriber": "no",

"block_plugin": "no",

"controller": "no",

"settings_form": "no"

}'

# Generate a controller non-interactively

drush generate controller --answers='{

"module": "my_custom_module",

"class": "MyController",

"services": ["entity_type.manager", "current_user"]

}'

# Generate a form non-interactively

drush generate form-simple --answers='{

"module": "my_custom_module",

"class": "ContactForm",

"form_id": "my_custom_module_contact",

"route": "yes",

"route_path": "/contact-us",

"route_title": "Contact Us",

"route_permission": "access content",

"link": "no"

}'

```

#### Method 2: Sequential --answer Flags

For simpler generators, use multiple --answer (or -a) flags in order:

```bash

# Answers are consumed in order of the prompts

drush generate controller --answer="my_module" --answer="PageController" --answer=""

# Short form

drush gen controller -a my_module -a PageController -a ""

```

#### Method 3: Discover Required Answers

Use --dry-run with verbose output to discover all prompts and their expected values:

```bash

# Preview generation and see all prompts

drush generate module -vvv --dry-run

# This shows you exactly what answers are needed

# Then re-run with --answers JSON

```

#### Method 4: Auto-Accept Defaults

Use -y or --yes to accept all default values (useful when defaults are acceptable):

```bash

# Accept all defaults

drush generate module -y

# Combine with some answers to override specific defaults

drush generate module --answer="My Module" -y

```

#### Complete Non-Interactive Examples

Generate a block plugin:

```bash

drush generate plugin:block --answers='{

"module": "my_custom_module",

"plugin_id": "my_custom_block",

"admin_label": "My Custom Block",

"category": "Custom",

"class": "MyCustomBlock",

"services": ["entity_type.manager"],

"configurable": "no",

"access": "no"

}'

```

Generate a service:

```bash

drush generate service --answers='{

"module": "my_custom_module",

"service_name": "my_custom_module.helper",

"class": "HelperService",

"services": ["database", "logger.factory"]

}'

```

Generate an event subscriber:

```bash

drush generate event-subscriber --answers='{

"module": "my_custom_module",

"class": "MyEventSubscriber",

"event": "kernel.request"

}'

```

Generate a Drush command:

```bash

drush generate drush:command-file --answers='{

"module": "my_custom_module",

"class": "MyCommands",

"services": ["entity_type.manager"]

}'

```

#### Common Answer Keys Reference

| Generator | Common Answer Keys |

|-----------|-------------------|

| module | name, machine_name, description, package, dependencies, install_file, libraries, permissions, event_subscriber, block_plugin, controller, settings_form |

| controller | module, class, services |

| form-simple | module, class, form_id, route, route_path, route_title, route_permission, link |

| form-config | module, class, form_id, route, route_path, route_title |

| plugin:block | module, plugin_id, admin_label, category, class, services, configurable, access |

| service | module, service_name, class, services |

| event-subscriber | module, class, event |

#### Best Practices for AI-Assisted Development

1. Always use --answers JSON - Most reliable for deterministic generation
2. Validate with --dry-run first - Preview output before writing files
3. Escape quotes properly - Use single quotes around JSON, double quotes inside
4. Chain with config export - Always export config after field creation:

```bash

drush field:create node article --field-name=field_subtitle && drush cex -y

```

1. Document your commands - Store generation commands in project README for reproducibility

#### Troubleshooting

"Missing required answer" error:

```bash

# Use -vvv to see which answer is missing

drush generate module -vvv --answers='{"name": "Test"}'

```

JSON parsing errors:

```bash

# Ensure proper escaping - use single quotes outside, double inside

drush generate module --answers='{"name": "Test Module"}' # Correct

drush generate module --answers="{"name": "Test Module"}" # Wrong - shell interprets braces

```

Interactive prompt still appears:

```bash

# Some prompts may not have defaults - provide all required answers

# Use --dry-run first to identify all prompts

drush generate module -vvv --dry-run 2>&1 | grep -E "^\s*\?"

```

```bash

drush cr # Clear cache

drush cex -y # Export config

drush cim -y # Import config

drush updb -y # Run updates

drush en module_name # Enable module

drush pmu module_name # Uninstall module

drush ws --severity=error # Watch logs

drush php:eval "code" # Run PHP

# Code generation (see CLI-First Development above)

drush generate # List all generators

drush gen module # Generate module (gen is alias)

drush field:create # Create field (fc is alias)

drush entity:create # Create entity content

```

• Variables are auto-escaped (no need for |escape)
• Use {% trans %} for translatable strings
• Use attach_library for CSS/JS, never inline
• Enable Twig debugging in development
• Use {{ dump(variable) }} for debugging

```twig

{# Correct - uses translation #}

{% trans %}Hello {{ name }}{% endtrans %}

{# Attach library #}

{{ attach_library('my_module/my-library') }}

{# Safe markup (already sanitized) #}

{{ content|raw }}

```

1. [ ] Searched drupal.org for existing modules?
2. [ ] Checked if a Recipe exists (Drupal 10.3+)?
3. [ ] Reviewed similar contrib modules for patterns?
4. [ ] Confirmed no suitable solution exists?
5. [ ] Planned test coverage?
6. [ ] Defined config schema for any custom config?
7. [ ] Using dependency injection (no static calls)?

Key Differences

| Feature | Drupal 10 | Drupal 11 |

|---------|-----------|-----------|

| PHP Version | 8.1+ | 8.3+ |

| Symfony | 6.x | 7.x |

| Hooks | Procedural or OOP | OOP preferred (attributes) |

| Annotations | Supported | Deprecated (use attributes) |

| jQuery | Included | Optional |

Writing Compatible Code (D10.3+ and D11)

Use PHP attributes for plugins (works in D10.2+, required style for D11):

```php

// Modern style (D10.2+, required for D11)

#[Block(

id: 'my_block',

admin_label: new TranslatableMarkup('My Block'),

)]

class MyBlock extends BlockBase {}

// Legacy style (still works but discouraged)

/**

* @Block(

* id = "my_block",

* admin_label = @Translation("My Block"),

* )

*/

```

Use OOP hooks (D10.3+):

```php

// Modern OOP hooks (D10.3+)

// src/Hook/MyModuleHooks.php

namespace Drupal\my_module\Hook;

use Drupal\Core\Hook\Attribute\Hook;

final class MyModuleHooks {

#[Hook('form_alter')]

public function formAlter(&$form, FormStateInterface $form_state, $form_id): void {

// ...

}

#[Hook('node_presave')]

public function nodePresave(NodeInterface $node): void {

// ...

}

}

```

Register hooks class in services.yml:

```yaml

services:

Drupal\my_module\Hook\MyModuleHooks:

autowire: true

```

Procedural hooks still work but should be in .module file only for backward compatibility.

Deprecated APIs to Avoid

```php

// DEPRECATED - don't use

drupal_set_message() // Use messenger service

format_date() // Use date.formatter service

entity_load() // Use entity_type.manager

db_select() // Use database service

drupal_render() // Use renderer service

\Drupal::l() // Use Link::fromTextAndUrl()

```

Check Deprecations

```bash

# Run deprecation checks

./vendor/bin/drupal-check modules/custom/

# Or with PHPStan

./vendor/bin/phpstan analyze modules/custom/ --level=5

```

info.yml Compatibility

```yaml

# Support both D10 and D11

core_version_requirement: ^10.3 || ^11

# D11 only

core_version_requirement: ^11

```

Recipes (D10.3+)

Drupal Recipes provide reusable configuration packages:

```bash

# Apply a recipe

php core/scripts/drupal recipe core/recipes/standard

# Community recipes

composer require drupal/recipe_name

php core/scripts/drupal recipe recipes/contrib/recipe_name

```

When to use Recipes vs Modules:

• Recipes: Configuration-only, site building, content types, views
• Modules: Custom PHP code, new functionality, APIs

Testing Compatibility

```bash

# Test against both versions in CI

jobs:

test-d10:

env:

DRUPAL_CORE: ^10.3

test-d11:

env:

DRUPAL_CORE: ^11

```

Migration Planning

Before upgrading D10 → D11:

1. Run drupal-check for deprecations
2. Update all contrib modules to D11-compatible versions
3. Convert annotations to attributes
4. Consider moving hooks to OOP style
5. Test thoroughly in staging environment

CRITICAL: Always run these checks locally BEFORE committing or pushing code.

CI pipeline failures are embarrassing and waste time. Catch issues locally first.

Required: Coding Standards (PHPCS)

```bash

# Check for coding standard violations

./vendor/bin/phpcs -p --colors modules/custom/

# Auto-fix what can be fixed

./vendor/bin/phpcbf modules/custom/

# Check specific file

./vendor/bin/phpcs path/to/MyClass.php

```

Common PHPCS errors to watch for:

• Missing trailing commas in multi-line function declarations
• Nullable parameters without ? type hint
• Missing docblocks
• Incorrect spacing/indentation

DDEV Shortcut

```bash

# Run inside DDEV

ddev exec ./vendor/bin/phpcs -p modules/custom/

ddev exec ./vendor/bin/phpcbf modules/custom/

```

Recommended: Full Pre-Commit Checklist

```bash

# 1. Coding standards

./vendor/bin/phpcs -p modules/custom/

# 2. Static analysis (if configured)

./vendor/bin/phpstan analyze modules/custom/

# 3. Deprecation checks

./vendor/bin/drupal-check modules/custom/

# 4. Run tests

./vendor/bin/phpunit modules/custom/my_module/tests/

```

Git Pre-Commit Hook (Optional)

Create .git/hooks/pre-commit:

```bash

#!/bin/bash

./vendor/bin/phpcs --standard=Drupal,DrupalPractice modules/custom/ || exit 1

```

Make executable: chmod +x .git/hooks/pre-commit

Installing PHPCS with Drupal Standards

```bash

composer require --dev drupal/coder

./vendor/bin/phpcs --config-set installed_paths vendor/drupal/coder/coder_sniffer

```

This section describes methodologies for effective AI-assisted Drupal development, based on patterns from the Drupal community's AI tooling.

The Context-First Approach

CRITICAL: Always gather context before generating code. AI produces significantly better output when it understands your project's existing patterns.

#### Step 1: Find Similar Files

Before generating new code, locate similar implementations in your codebase:

```bash

# Find similar services

find modules/custom -name "*.services.yml" -exec grep -l "entity_type.manager" {} \;

# Find similar forms

find modules/custom -name "*Form.php" -type f

# Find similar controllers

find modules/custom -path "/Controller/.php" -type f

# Find similar plugins

find modules/custom -path "/Plugin/Block/.php" -type f

```

Why this matters: When you show existing code patterns to AI, it will:

• Match your naming conventions
• Use the same dependency injection patterns
• Follow your project's architectural style
• Integrate consistently with existing code

#### Step 2: Understand Project Patterns

Before requesting code generation, identify:

```markdown

1. Naming patterns

- Service naming: my_module.helper vs my_module_helper

- Class naming: MyModuleHelper vs HelperService

- File organization: flat vs nested directories

1. Dependency patterns

- Which services are commonly injected?

- How is logging handled?

- How are entities loaded?

1. Configuration patterns

- Where is config stored?

- How are settings forms structured?

- What schema patterns are used?

```

#### Step 3: Provide Context in Requests

Structure your requests with explicit context:

```markdown

Bad request:

"Create a service that processes nodes"

Good request:

"Create a service that processes article nodes.

Context:

• See existing service pattern in modules/custom/my_module/src/ArticleManager.php
• Inject entity_type.manager and logger.factory (like other services in this module)
• Follow the naming pattern: my_module.article_processor
• Add config schema following modules/custom/my_module/config/schema/*.yml pattern"

```

Structured Prompting for Drupal Tasks

Use hierarchical prompts for complex generation tasks. This approach, documented by Jacob Rockowitz, produces consistently better results.

#### Prompt Template Structure

```markdown

[One sentence describing what you want to create]

• Module name: my_custom_module
• Module path: modules/custom/my_custom_module
• Drupal version: 10.3+ / 11
• PHP version: 8.2+

• [Specific requirement 1]
• [Specific requirement 2]
• [Specific requirement 3]

• Use constructor property promotion
• Use PHP 8 attributes for plugins
• Inject all dependencies (no \Drupal::service())
• Include proper docblocks
• Follow Drupal coding standards

• [Path to similar implementation]
• [Path to similar implementation]

• [File 1]: [Description]
• [File 2]: [Description]

```

#### Example: Creating a Block Plugin

```markdown

Create a block that displays recent articles with a configurable limit.

• Module name: my_articles
• Module path: modules/custom/my_articles
• Drupal version: 10.3+
• PHP version: 8.2+

• Display recent article nodes (type: article)
• Configurable number of items (default: 5)
• Show title, date, and teaser
• Cache per page with article list tag
• Access: view published content permission

• Use #[Block] attribute (not annotation)
• Inject entity_type.manager and date.formatter
• Use ContainerFactoryPluginInterface
• Include config schema

• modules/custom/my_articles/src/Plugin/Block/FeaturedArticleBlock.php

• src/Plugin/Block/RecentArticlesBlock.php
• config/schema/my_articles.schema.yml (update)

```

The Inside-Out Approach

Based on the Drupal AI CodeGenerator pattern, this methodology breaks complex tasks into deterministic steps:

#### Phase 1: Task Classification

Determine what type of task is being requested:

| Type | Description | Approach |

|------|-------------|----------|

| Create | New file/component needed | Generate with DCG, then customize |

| Edit | Modify existing code | Read first, then targeted changes |

| Information | Question about code/architecture | Search and explain |

| Composite | Multiple steps needed | Break down, execute sequentially |

#### Phase 2: Solvability Check

Before generating, verify:

```markdown

✓ Required dependencies available?

✓ Target directory exists and is writable?

✓ No conflicting files/classes?

✓ All referenced services/classes exist?

✓ Compatible with Drupal version?

```

#### Phase 3: Scaffolding First

Use DCG to scaffold, then customize. This ensures Drupal best practices:

```bash

# 1. Generate base structure

drush generate plugin:block --answers='{

"module": "my_module",

"plugin_id": "recent_articles",

"admin_label": "Recent Articles",

"class": "RecentArticlesBlock"

}'

# 2. Review generated code

cat modules/custom/my_module/src/Plugin/Block/RecentArticlesBlock.php

# 3. Customize with specific requirements

# (AI edits the generated file to add business logic)

```

#### Phase 4: Auto-Generate Tests

Always generate tests alongside code:

```bash

# Generate kernel test for the new functionality

drush generate test:kernel --answers='{

"module": "my_module",

"class": "RecentArticlesBlockTest"

}'

```

Iterative Development Workflow

Expect 80% completion from AI-generated code. Plan for refinement cycles.

#### The Realistic Workflow

```

┌─────────────────────────────────────────────────────────────┐

│ 1. GATHER CONTEXT │

│ - Find similar files │

│ - Understand patterns │

│ - Document requirements │

├─────────────────────────────────────────────────────────────┤

│ 2. GENERATE (AI does ~80%) │

│ - Use structured prompt │

│ - Scaffold with DCG │

│ - Generate business logic │

├─────────────────────────────────────────────────────────────┤

│ 3. REVIEW & REFINE (Human does ~20%) │

│ - Check security (XSS, SQL injection, access) │

│ - Verify DI compliance │

│ - Validate config schema │

│ - Run PHPCS and fix issues │

├─────────────────────────────────────────────────────────────┤

│ 4. TEST │

│ - Run generated tests │

│ - Add edge case tests │

│ - Manual smoke testing │

├─────────────────────────────────────────────────────────────┤

│ 5. ITERATE (if needed) │

│ - Fix failing tests │

│ - Address review feedback │

│ - Refine based on testing │

└─────────────────────────────────────────────────────────────┘

```

#### Common Refinement Tasks

| Issue | Solution |

|-------|----------|

| PHPCS errors | Run phpcbf for auto-fix, manual fix for complex issues |

| Missing DI | Add to constructor, update create() method |

| No cache metadata | Add #cache with tags, contexts, max-age |

| Missing access check | Add permission check or access handler |

| No config schema | Create schema file matching config structure |

| Hardcoded strings | Wrap in $this->t() with proper placeholders |

Integration with Drupal AI Module

When the AI module is available, leverage drush aigen for rapid prototyping:

```bash

# Check if AI Generation is available

drush pm:list --filter=ai_generation

# Generate a complete content type

drush aigen "Create a content type called 'Event' with fields: title, date (datetime), location (text), description (formatted text), image (media reference)"

# Generate a view

drush aigen "Create a view showing upcoming events sorted by date with a calendar display"

# Generate a custom module

drush aigen "Create a module that sends email notifications when new events are created"

```

Important: Always review AI-generated code. The AI Generation module is experimental and intended for development only.

Prompt Patterns for Common Tasks

#### Content Type with Fields

```markdown

Create a content type for [purpose].

Content type:

• Machine name: [machine_name]
• Label: [Human Label]
• Description: [Description]
• Publishing options: published by default, create new revision
• Display author and date: no

Fields:

1. [field_name] ([field_type]): [description] - [required/optional]
2. [field_name] ([field_type]): [description] - [required/optional]

After creation, export config with: drush cex -y

```

#### Custom Service

```markdown

Create a service for [purpose].

Service:

• Name: [module].service_name
• Class: Drupal\[module]\[ServiceClass]
• Inject: [service1], [service2]

Methods:

• methodName(params): return_type - [description]
• methodName(params): return_type - [description]

Include:

• Interface definition
• services.yml entry
• PHPDoc with @param and @return

```

#### Event Subscriber

```markdown

Create an event subscriber for [purpose].

Subscriber:

• Class: Drupal\[module]\EventSubscriber\[ClassName]
• Event: [event.name]
• Priority: [0-100]

Behavior:

• [Describe what should happen when event fires]

Include:

• services.yml entry with tags
• Proper type hints

```

Debugging AI-Generated Code

When generated code doesn't work:

```bash

# 1. Check for PHP syntax errors

php -l modules/custom/my_module/src/MyClass.php

# 2. Clear all caches

drush cr

# 3. Check service container

drush devel:services | grep my_module

# 4. Check for missing use statements

grep -n "^use" modules/custom/my_module/src/MyClass.php

# 5. Verify class is autoloaded

drush php:eval "class_exists('Drupal\my_module\MyClass') ? print 'Found' : print 'Not found';"

# 6. Check logs

drush ws --severity=error --count=20

```

• [Drupal Testing Types](https://www.drupal.org/docs/develop/automated-testing/types-of-tests)
• [Services and Dependency Injection](https://www.drupal.org/docs/drupal-apis/services-and-dependency-injection)
• [Hooks vs Events](https://www.specbee.com/blogs/hooks-vs-events-in-drupal-making-informed-choice)
• [PHPUnit in Drupal](https://www.drupal.org/docs/develop/automated-testing/phpunit-in-drupal)
• [Drupal 11 Readiness](https://www.drupal.org/docs/upgrading-drupal/how-to-prepare-your-drupal-7-or-8-site-for-drupal-9/deprecation-checking-and-correction-tools)
• [OOP Hooks](https://www.drupal.org/docs/develop/creating-modules/implementing-hooks-in-drupal-11)
• [Drupal Recipes](https://www.drupal.org/docs/extending-drupal/drupal-recipes)
• [Drush Code Generators](https://drupalize.me/tutorial/develop-drupal-modules-faster-drush-code-generators)
• [Drush Generate Command](https://www.drush.org/13.x/commands/generate/)
• [Drush field:create](https://www.drush.org/13.x/commands/field_create/)
• [Scaffold Custom Content Entity with Drush](https://drupalize.me/tutorial/scaffold-custom-content-entity-type-drush-generators)
• [Drupal Code Generator (DCG)](https://github.com/Chi-teck/drupal-code-generator)
• [Building a Drupal Module Using AI - Jacob Rockowitz](https://www.jrockowitz.com/blog/building-a-drupal-model-using-al)
• [AI Generation Module](https://www.drupal.org/project/ai_generation)
• [AI Module](https://www.drupal.org/project/ai)
• [CodeGenerator Agent Pattern](https://git.drupalcode.org/-/snippets/261)