Prerequisites

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🚀 Feature Proposal

Introduce startup validation in Fastify to check consistency between route parameters in path strings and schema definitions.

Motivation

Ensuring route parameter consistency to prevent runtime errors

Example

// Inconsistent route params and schema could lead to unnoticed issues until runtime
fastify.get('/item/:itemId', {
  schema: {
    params: {
      type: 'object',
      properties: {
        id: { type: 'string' } // Potential issue: 'itemId' in route vs 'id' in schema
      }
    }
  },
  handler: (request, reply) => { /* ... */ }
});

A pre-runtime check could catch these mismatches early, enhancing developer experience and application stability.