refactor(core): validate user config in a more expressive way

zod unions are exclusive, so the UserConfig type couldn't be kept as a union either for having at least a colors, typographies or pages output.

This check has been moved to a runtime zod refine custom validation.

packages/core/package.json

@@ -15,7 +15,8 @@
   },
   "dependencies": {
     "node-fetch": "2",
-    "prettier": "^3.0.2"
+    "prettier": "^3.0.2",
+    "zod": "^3.22.2"
   },
   "devDependencies": {
     "@types/node": "^20.5.0",

packages/core/src/lib/config/index.ts

@@ -8,9 +8,10 @@ function normalizePenpotExportUserFileConfig(
 ): FileConfig {
   return {
     fileId: userConfig.fileId,
-    colors: 'colors' in userConfig ? userConfig.colors : [],
+    colors: userConfig.colors !== undefined ? userConfig.colors : [],
-    typographies: 'typographies' in userConfig ? userConfig.typographies : [],
+    typographies:
-    pages: 'pages' in userConfig ? userConfig.pages : [],
+      userConfig.typographies !== undefined ? userConfig.typographies : [],
+    pages: userConfig.pages !== undefined ? userConfig.pages : [],
   }
 }
 

packages/core/src/lib/config/validator.ts

@@ -1,143 +1,78 @@
-import { UserFileConfig, UserConfig } from '../types'
+import { z } from 'zod'
 
-import { PagesConfig, ColorsConfig, TypographiesConfig } from './types'
+import { UserConfig } from '../types'
 
-class FileIdConfigError extends Error {
+const accessTokenSchema = z.string({
-  constructor() {
+  required_error: '.accessToken is required',
-    super(`Missing or invalid .fileId in penpot export config.`)
+  invalid_type_error: '.accessToken must be a string',
-  }
+})
-}
+const instanceSchema = z
+  .string({
+    required_error: '.instance is required',
+    invalid_type_error: '.instance must be a string',
+  })
+  .url({
+    message: '.instance must be a valid URL',
+  })
+const fileIdSchema = z
+  .string({
+    required_error: '.fileId is required',
+    invalid_type_error: '.fileId must be a string',
+  })
+  .uuid({
+    message: '.fileId must be a valid UUID',
+  })
+const pageIdSchema = z
+  .string({
+    required_error: '.pageId is required',
+    invalid_type_error: '.pageId must be a string',
+  })
+  .uuid({
+    message: '.pageId must be a valid UUID',
+  })
+const outputSchema = z.string({
+  required_error: '.output is required',
+  invalid_type_error: '.output must be a string',
+})
 
-class AssetListConfigError extends Error {
+const userColorsConfigSchema = z.object({
-  constructor(assetType: 'colors' | 'typographies' | 'pages') {
+  output: outputSchema,
-    super(`Invalid .${assetType} list in penpot export config.`)
+})
-  }
+const userTypographiesConfigSchema = z.object({
-}
+  output: outputSchema,
+})
+const userPagesConfigSchema = z.object({
+  output: outputSchema,
+  pageId: pageIdSchema,
+})
 
-class OutputPathConfigError extends Error {
+const userFileConfigSchema = z
-  constructor(index: number) {
+  .object({
-    super(`Missing or invalid .path in penpot export config at index ${index}.`)
+    fileId: fileIdSchema,
-  }
+    colors: z.optional(z.array(userColorsConfigSchema)),
-}
+    typographies: z.optional(z.array(userTypographiesConfigSchema)),
-
+    pages: z.optional(z.array(userPagesConfigSchema)),
-class PageIdConfigError extends Error {
+  })
-  constructor(index: number) {
+  .refine(
-    super(
+    (object) => {
-      `Missing or invalid .pageId in penpot export config at index ${index}.`,
+      if ('colors' in object) return true
+      if ('typographies' in object) return true
+      if ('pages' in object) return true
+      return false
+    },
+    {
+      message:
+        'Each file in .files is required to have at least one of .colors, .typographies or .pages properties',
+    },
   )
-  }
-}
 
-function validateUserColorsConfig(
+const userConfigSchema = z.object({
-  colorsConfig: object,
+  accessToken: accessTokenSchema,
-  index: number,
+  instance: z.optional(instanceSchema),
-): colorsConfig is ColorsConfig {
+  files: z
-  if (!('output' in colorsConfig) || typeof colorsConfig.output !== 'string')
+    .array(userFileConfigSchema)
-    throw new OutputPathConfigError(index)
+    .nonempty({ message: '.files is required to have at least one item' }),
+})
 
-  return true
+export const validateUserConfig = (userConfig: object): UserConfig =>
-}
+  userConfigSchema.parse(userConfig)
-
-function validateUserTypographiesConfig(
-  typographiesConfig: object,
-  index: number,
-): typographiesConfig is TypographiesConfig {
-  if (
-    !('output' in typographiesConfig) ||
-    typeof typographiesConfig.output !== 'string'
-  )
-    throw new OutputPathConfigError(index)
-
-  return true
-}
-
-function validateUserPagesConfig(
-  pagesConfig: object,
-  index: number,
-): pagesConfig is PagesConfig {
-  if (!('output' in pagesConfig) || typeof pagesConfig.output !== 'string')
-    throw new OutputPathConfigError(index)
-
-  if (!('pageId' in pagesConfig) || typeof pagesConfig.pageId !== 'string')
-    throw new PageIdConfigError(index)
-
-  return true
-}
-
-function validateUserFileConfig(
-  userConfig: object,
-): userConfig is UserFileConfig {
-  if (!('fileId' in userConfig) || typeof userConfig.fileId !== 'string')
-    throw new FileIdConfigError()
-
-  if ('colors' in userConfig) {
-    if (!Array.isArray(userConfig.colors))
-      throw new AssetListConfigError('colors')
-    userConfig.colors.every(validateUserColorsConfig)
-  }
-
-  if ('typographies' in userConfig) {
-    if (!Array.isArray(userConfig.typographies))
-      throw new AssetListConfigError('typographies')
-    userConfig.typographies.every(validateUserTypographiesConfig)
-  }
-
-  if ('pages' in userConfig) {
-    if (!Array.isArray(userConfig.pages))
-      throw new AssetListConfigError('pages')
-    userConfig.pages.every(validateUserPagesConfig)
-  }
-
-  return true
-}
-
-class AccessTokenConfigError extends Error {
-  constructor() {
-    super('Missing or invalid .accessToken in penpot export config.')
-  }
-}
-
-class InvalidInstanceUrlConfigError extends Error {
-  constructor() {
-    super('Invalid .instance URL in penpot export config.')
-  }
-}
-
-class FilesConfigError extends Error {
-  constructor() {
-    super('Missing or invalid .files in penpot export config.')
-  }
-}
-
-export function validateUserConfig(
-  userConfig: object,
-): userConfig is UserConfig {
-  if (
-    !('accessToken' in userConfig) ||
-    typeof userConfig.accessToken !== 'string'
-  )
-    throw new AccessTokenConfigError()
-
-  if ('instance' in userConfig && userConfig.instance !== undefined) {
-    if (typeof userConfig.instance !== 'string')
-      throw new InvalidInstanceUrlConfigError()
-
-    try {
-      new URL(userConfig.instance)
-    } catch (error) {
-      if (error instanceof TypeError) throw new InvalidInstanceUrlConfigError()
-      throw error
-    }
-  }
-
-  if (
-    !('files' in userConfig) ||
-    !Array.isArray(userConfig.files) ||
-    userConfig.files.length === 0
-  )
-    throw new FilesConfigError()
-
-  userConfig.files.every(validateUserFileConfig)
-
-  return true
-}

packages/core/src/lib/index.ts

@@ -11,12 +11,9 @@ export default async function penpotExport(
   userConfig: object,
   rootProjectPath: string,
 ) {
-  if (!validateUserConfig(userConfig))
+  const parsedUserConfig = validateUserConfig(userConfig)
-    throw new Error(
-      'Error validating user config. This is probably an error in penpot-export code.',
-    )
 
-  const config = normalizePenpotExportUserConfig(userConfig)
+  const config = normalizePenpotExportUserConfig(parsedUserConfig)
   const penpot = new Penpot({
     baseUrl: config.instance,
     accessToken: config.accessToken,

packages/core/src/lib/types.ts

@@ -11,11 +11,10 @@ import type {
 
 export type UserFileConfig = {
   fileId: string
-} & (
+  colors?: ColorsConfig[]
-  | { colors: ColorsConfig[] }
+  typographies?: TypographiesConfig[]
-  | { typographies: TypographiesConfig[] }
+  pages?: PagesConfig[]
-  | { pages: PagesConfig[] }
+}
-)
 
 export interface UserConfig {
   instance?: string

yarn.lock

@@ -315,3 +315,8 @@ yn@3.1.1:
   version "3.1.1"
   resolved "https://registry.yarnpkg.com/yn/-/yn-3.1.1.tgz#1e87401a09d767c1d5eab26a6e4c185182d2eb50"
   integrity sha512-Ux4ygGWsu2c7isFWe8Yu1YluJmqVhxqK2cLXNQA5AcC3QfbGNpM7fu0Y8b/z16pXLnFxZYvWhd3fhBY9DLmC6Q==
+
+zod@^3.22.2:
+  version "3.22.2"
+  resolved "https://registry.yarnpkg.com/zod/-/zod-3.22.2.tgz#3add8c682b7077c05ac6f979fea6998b573e157b"
+  integrity sha512-wvWkphh5WQsJbVk1tbx1l1Ly4yg+XecD+Mq280uBGt9wa5BKSWf4Mhp6GmrkPixhMxmabYY7RbzlwVP32pbGCg==