trailer() — fastify Function Reference

Architecture documentation for the trailer() function in reply.js from the fastify codebase.

Function javascript CoreKernel InstanceFactory

Entity Profile

CoreKernel→ InstanceFactory→ trailer() — fastify Function Reference

Dependency Diagram

graph TD
  59b5093c_d8b5_b599_1c7c_b6b7c6258d22["trailer()"]
  4bcd71dc_1ec2_5fe8_b8ff_4a371e392925["reply.js"]
  59b5093c_d8b5_b599_1c7c_b6b7c6258d22 -->|defined in| 4bcd71dc_1ec2_5fe8_b8ff_4a371e392925
  style 59b5093c_d8b5_b599_1c7c_b6b7c6258d22 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

lib/reply.js lines 289–300

Reply.prototype.trailer = function (key, fn) {
  key = key.toLowerCase()
  if (INVALID_TRAILERS.has(key)) {
    throw new FST_ERR_BAD_TRAILER_NAME(key)
  }
  if (typeof fn !== 'function') {
    throw new FST_ERR_BAD_TRAILER_VALUE(key, typeof fn)
  }
  if (this[kReplyTrailers] === null) this[kReplyTrailers] = {}
  this[kReplyTrailers][key] = fn
  return this
}