Metadata

oRPC procedures support metadata — simple key-value pairs that customize behavior.

Basic Example

import { os } from '@orpc/server'

interface ORPCMetadata {
  cache?: boolean
}

const base = os
  .$meta<ORPCMetadata>({}) // require initial metadata
  .use(async ({ procedure, next, path }, input, output) => {
    if (!procedure['~orpc'].meta.cache) {
      return await next()
    }

    const cacheKey = path.join('/') + JSON.stringify(input)

    if (db.has(cacheKey)) {
      return output(db.get(cacheKey))
    }

    const result = await next()

    db.set(cacheKey, result.output)

    return result
  })

const example = base
  .meta({ cache: true })
  .handler(() => {
    // Implement your procedure logic
  })

.meta can be called multiple times; each call spread-merges new metadata with existing.