refactor: splitting package into constituent modules

index.js

@@ -0,0 +1,28 @@
+'use strict'
+
+const fp = require('fastify-plugin')
+const createAuthHandler = require('./lib/auth-handler')
+const { ALLOWED_RELATIONS, DEFAULT_RELATION } = require('./lib/constants')
+
+/**
+ * @type {typeof import('./types/index').fastifyAuth}
+ */
+function fastifyAuth (fastify, opts, next) {
+  const specifiedRelation = opts.defaultRelation
+  if (specifiedRelation && !ALLOWED_RELATIONS.includes(specifiedRelation)) {
+    const error = new Error(`The value of default relation should be one of [${ALLOWED_RELATIONS}], not "${specifiedRelation}"`)
+    return next(error)
+  }
+  const pluginOptions = {
+    defaultRelation: specifiedRelation || DEFAULT_RELATION
+  }
+  fastify.decorate('auth', createAuthHandler(pluginOptions))
+  next()
+}
+
+module.exports = fp(fastifyAuth, {
+  fastify: '5.x',
+  name: '@fastify/auth'
+})
+module.exports.default = fastifyAuth
+module.exports.fastifyAuth = fastifyAuth

lib/auth-handler.js

@@ -0,0 +1,87 @@
+'use strict'
+
+const reusify = require('reusify')
+const AuthState = require('./auth-state')
+const { ALLOWED_RELATIONS } = require('./constants')
+
+/**
+ * @param { import('../types/index').FastifyAuthPluginOptions } pluginOptions
+ * @returns {(
+ *   handlers: import('../types/index').FastifyAuthHandlerArray,
+ *   authOptions?: import('../types/index').FastifyAuthOptions
+ * ) => (request: import('fastify').FastifyRequest, reply: import('fastify').FastifyReply, done: (error?: Error) => void) => void}
+ */
+function createAuthHandler (pluginOptions) {
+  return function (handlers, authOptions) {
+    if (!Array.isArray(handlers)) {
+      throw new TypeError(`You must give an array of functions, not "${typeof handlers}"`)
+    }
+    if (!handlers.length) {
+      throw new Error('Missing auth functions')
+    }
+    handlers.forEach((fn, i) => {
+      if (!Array.isArray(fn)) {
+        handlers[i] = fn.bind(this)
+        return
+      }
+      fn.forEach((nestedFn, j) => {
+        if (Array.isArray(nestedFn)) {
+          throw new TypeError('Nesting sub-arrays is not supported')
+        }
+        fn[j] = nestedFn.bind(this)
+      })
+    })
+    const instance = reusify(AuthState)
+    const options = resolveAuthOptions(pluginOptions, authOptions)
+    return createRequestHandler(instance, handlers, options)
+  }
+}
+
+/**
+ * @param {import('../types/index').FastifyAuthPluginOptions} pluginOptions
+ * @param {import('../types/index').FastifyAuthOptions} authOptions
+ * @returns {Required<import('../types/index').FastifyAuthOptions>}
+ */
+function resolveAuthOptions (pluginOptions, authOptions) {
+  const resolvedOptions = {
+    relation: pluginOptions.defaultRelation,
+    run: null,
+    ...authOptions
+  }
+  const { relation, run } = resolvedOptions
+  if (!ALLOWED_RELATIONS.includes(relation)) {
+    throw new Error(`The value of default relation should be one of [${ALLOWED_RELATIONS}], not "${relation}"`)
+  }
+  if (run && run !== 'all') {
+    throw new Error(`The value of run option must be "all", not "${run}"`)
+  }
+  return resolvedOptions
+}
+
+/**
+ * @param {{ get(): import('./auth-state'), release(obj: import('./auth-state')): void }} instance
+ * @param {import('../types/index').FastifyAuthHandlerArray} handlers
+ * @param {Required<import('../types/index').FastifyAuthOptions>} options
+ * @returns {(request: import('fastify').FastifyRequest, reply: import('fastify').FastifyReply, done: (error?: Error) => void) => void}
+ */
+function createRequestHandler (instance, handlers, options) {
+  return (request, reply, done) => {
+    const state = instance.get()
+    state.i = 0
+    state.j = 0
+    state.handlers = handlers
+    state.options = options
+    state.request = request
+    state.reply = reply
+    state.done = done
+    state.currentError = null
+    state.skipFurtherErrors = false
+    state.skipFurtherArrayErrors = false
+    state.onComplete = () => instance.release(state)
+    state.nextAuthHandler()
+  }
+}
+
+module.exports = createAuthHandler
+module.exports.resolveAuthOptions = resolveAuthOptions
+module.exports.createRequestHandler = createRequestHandler