Service Locator Pattern

Kind: pattern

Layer: Extensibility Core

Record: architecture:service-locator-pattern

Severity: discouraged

Scope: runtime, dependency access

Canonical: Ontology

A design pattern in which code fetches its dependencies from a global registry at the point of use.

Listed in Architecture principles, after Registry Pattern and before Feature Toggle.

Requires

• Registry

Reinforces

• Runtime Lookup

Enables

• Late Resolution

In tension with

• Testability
• Dependency Inversion Principle (DIP)
• Explicit Dependencies

Tensions

• Service Locator Pattern / Testability
• Service Locator Pattern / Dependency Inversion Principle (DIP)
• Service Locator Pattern / Explicit Dependencies

Violated by

• Hidden Dependency

Refactored by

• Dependency Injection

Severity

• discouraged

Category

• Plugin / Extensibility / IoC

Linked from

• Correctness / Determinism / Verification
• SOLID / Object-Oriented Design
• Causality / Ordering / Distributed Time
• Plugin / Extensibility / IoC
• Severity levels
• The resolutions