transformPatternToRoute

Kind: Function

Source: packages/microservices/utils/transform-pattern.utils.ts

Part of: Microservices

Transforms the Pattern to Route safely.

transformPatternToRoute converts a microservice message pattern into a route-like string that can be used for transport-level routing or identification. String patterns are returned unchanged, while object patterns are flattened into slash-separated key/value segments; unsupported pattern values safely resolve to an empty string.

Signature

ts
function transformPatternToRoute(pattern: MsPattern, depth, maxDepth, maxKeys): string

Parameters

Returns: string

Diagram

mermaid
graph LR
  A[Microservice Pattern] --> B{Pattern type}
  B -->|String| C[Return pattern unchanged]
  B -->|Object| D[Convert each key/value to segment]
  D --> E[Join segments with /]
  E --> F[Route string]
  B -->|Invalid or unsupported| G[Return empty string]

Usage

ts
import { transformPatternToRoute } from '@nestjs/microservices/utils/transform-pattern.utils';

const stringRoute = transformPatternToRoute('users.create');
// "users.create"

const objectRoute = transformPatternToRoute({
  service: 'users',
  action: 'create',
});
// "service/users/action/create"

const invalidRoute = transformPatternToRoute(null as any);
// ""

AI Coding Instructions

• Preserve string patterns exactly; do not normalize, trim, or add route separators to them.
• When passing object patterns, use stable and meaningful key ordering because property order determines the generated route.
• Handle potentially invalid or non-object pattern values before relying on the returned route in downstream transport logic.
• Keep this utility transport-agnostic; transport-specific routing behavior should be implemented by the caller or adapter.

Relationships

• IMPORTS → isNumber
• IMPORTS → isObject
• IMPORTS → isString