feat: add proxy support with node-fetch-native/proxy (#40)

Co-authored-by: ellipsis-dev[bot] <65095814+ellipsis-dev[bot]@users.noreply.github.com>

Author: JounQin

.changeset/great-steaks-melt.md

@@ -0,0 +1,6 @@
+---
+"@deeplx/cli": patch
+"@deeplx/core": patch
+---
+
+feat: add `proxy` support with `node-fetch-native/proxy`

package.json

@@ -35,7 +35,6 @@
     "@deeplx/core": "workspace:*",
     "@octokit/request": "^9.2.3",
     "@pkgr/rollup": "^6.0.3",
-    "@types/web": "^0.0.219",
     "@vercel/node": "^5.1.14",
     "@vitest/coverage-istanbul": "^3.1.1",
     "eslint": "^9.24.0",
@@ -51,10 +50,13 @@
     "typescript": "^5.8.3",
     "vite-tsconfig-paths": "^5.1.4",
     "vitest": "^3.1.1",
-    "yarn-berry-deduplicate": "^6.1.1"
+    "yarn-berry-deduplicate": "^6.1.3"
   },
   "resolutions": {
-    "prettier": "^3.5.3"
+    "node-fetch": "npm:node-fetch-native@^1.6.6",
+    "prettier": "^3.5.3",
+    "undici": "npm:undici@^7.8.0",
+    "undici-types": "npm:undici@^7.8.0"
   },
   "typeCoverage": {
     "atLeast": 100,

packages/@deeplx/cli/package.json

@@ -40,7 +40,7 @@
   "dependencies": {
     "@deeplx/core": "^0.1.1",
     "commander": "^13.1.0",
-    "node-fetch": "^3.3.2"
+    "node-fetch-native": "^1.6.6"
   },
   "publishConfig": {
     "access": "public"

packages/@deeplx/cli/src/fetch.ts

@@ -1,9 +1,7 @@
-import fetch, { Headers } from 'node-fetch'
+import fetch, { Headers } from 'node-fetch-native'
 
-// @ts-expect-error -- incompatible types
 // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 globalThis.fetch ??= fetch
 
-// @ts-expect-error -- incompatible types
 // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 globalThis.Headers ??= Headers

packages/@deeplx/core/package.json

@@ -48,6 +48,7 @@
     "translator"
   ],
   "dependencies": {
+    "node-fetch-native": "^1.6.6",
     "whatlang-node": "^0.1.0",
     "x-fetch": "^0.2.6"
   },

packages/@deeplx/core/src/constants.ts

@@ -1,3 +1,5 @@
+import type { HeadersInit } from 'undici'
+
 import type { ValueOf } from './types.ts'
 
 export const SUPPORTED_LANGUAGES = [
@@ -64,7 +66,7 @@ export const HTTP_STATUS_NOT_ALLOWED = 405
 export const HTTP_STATUS_INTERNAL_ERROR = 500
 export const HTTP_STATUS_SERVICE_UNAVAILABLE = 503
 
-export const COMMON_HEADERS: HeadersInit = {
+export const COMMON_HEADERS = {
   'Content-Type': 'application/json',
   'User-Agent': 'DeepL/1627620 CFNetwork/3826.500.62.2.1 Darwin/24.4.0',
   Accept: '*/*',
@@ -77,4 +79,4 @@ export const COMMON_HEADERS: HeadersInit = {
   'X-Product': 'translator',
   'X-App-Build': '1627620',
   'X-App-Version': '25.1',
-}
+} as const satisfies HeadersInit

packages/@deeplx/core/src/translate.ts

@@ -1,5 +1,6 @@
+import { createProxy } from 'node-fetch-native/proxy'
 import { detectLang } from 'whatlang-node'
-import { fetchApi } from 'x-fetch'
+import { xfetch } from 'x-fetch'
 
 import {
   API_URL,
@@ -29,15 +30,16 @@ import {
 // makeRequest makes an HTTP request to DeepL API
 const makeRequest = async (
   postData: PostData,
-  _proxyUrl?: string, // unsupported yet
+  proxyUrl?: string,
   dlSession?: string,
 ) => {
-  return fetchApi<TranslationResponse>(API_URL, {
+  return xfetch<TranslationResponse>(API_URL, {
     method: 'POST',
     body: formatPostString(postData),
     headers: dlSession
       ? { ...COMMON_HEADERS, Cookie: `dl_session=${dlSession}` }
       : COMMON_HEADERS,
+    ...createProxy({ url: proxyUrl }),
   })
 }