Requirement Diagram

Requirement diagrams help you document and visualize system requirements, their relationships, and how they are satisfied by design elements. This is valuable for requirements traceability in engineering projects.

Basic Example

requirementDiagram
    requirement UserAuthentication {
        id: REQ-001
        text: Users must authenticate before accessing the system
        risk: high
        verifymethod: test
    }

    element AuthService {
        type: module
    }

    AuthService - satisfies -> UserAuthentication

What You Get

Requirement diagrams have full IDE support:

• Syntax highlighting - Color-coded requirements, elements, and relationships
• Code completion - Suggestions for requirement types and verification methods
• Refactoring - Rename requirements and elements across the diagram
• Find usages - Track where requirements are referenced
• Code Vision - See relationship counts at a glance
• Navigation bar - Quick access to requirements in large documents
• Code folding - Collapse requirement definitions
• Formatting - Auto-format your diagram code
• Inspections - Detect undefined references and missing properties

Quick Syntax Reference

Requirement types:

• requirement - Functional requirement
• functionalRequirement - Functional requirement (explicit)
• performanceRequirement - Performance constraint
• interfaceRequirement - Interface specification
• physicalRequirement - Physical constraint
• designConstraint - Design limitation

Requirement properties:

requirementDiagram
    requirement Example {
        id: REQ-002
        text: Description of the requirement
        risk: low
        verifymethod: analysis
    }

Risk levels: low, medium, high

Verification methods: analysis, inspection, test, demonstration

Relationship types:

• - satisfies -> - Element satisfies requirement
• - traces -> - Requirement traces to another
• - contains -> - Requirement contains sub-requirements
• - derives -> - Requirement derives from another
• - refines -> - Requirement refines another
• - copies -> - Requirement copies another
• - verifies -> - Element verifies requirement

For the complete syntax reference, see the Mermaid.js Requirement Diagram documentation.