Merge pull request #140 from prisma/fix/windows-symlink

Fix Windows symlink EPERM error

Author: Divyendu Singh

example/package.json

@@ -5,6 +5,7 @@
   },
   "devDependencies": {
     "@types/lodash": "4.14.91",
+    "@types/node": "^11.13.0",
     "serverless-plugin-typescript": "1.1.5"
   }
 }

package.json

@@ -11,7 +11,7 @@
   "scripts": {
     "prepublish": "npm run build",
     "precommit": "npm run test",
-    "build": "rm -rf dist && tsc",
+    "build": "rimraf dist && tsc",
     "pretest": "npm run lint",
     "test": "jest",
     "lint": "tslint -c tslint.json 'src/**/*.ts'"
@@ -32,6 +32,7 @@
     "@types/lodash": "4.14.123",
     "jest": "24.5.0",
     "mock-fs": "4.8.0",
+    "rimraf": "^2.6.3",
     "ts-jest": "24.0.1",
     "tslint": "5.14.0",
     "typescript": "^3.4.1"

src/index.ts

@@ -136,14 +136,17 @@ export class TypeScriptPlugin {
   }
 
   async copyExtras() {
-    // include node_modules into build
-    if (!fs.existsSync(path.resolve(path.join(buildFolder, 'node_modules')))) {
-      fs.symlinkSync(path.resolve('node_modules'), path.resolve(path.join(buildFolder, 'node_modules')), 'junction')
+    const outPkgPath = path.resolve(path.join(buildFolder, 'package.json'))
+    const outModulesPath = path.resolve(path.join(buildFolder, 'node_modules'))
+
+    // Link or copy node_modules and package.json to .build so Serverless can
+    // exlcude devDeps during packaging
+    if (!fs.existsSync(outModulesPath)) {
+      await this.linkOrCopy(path.resolve('node_modules'), outModulesPath, 'junction')
     }
 
-    // include package.json into build so Serverless can exlcude devDeps during packaging
-    if (!fs.existsSync(path.resolve(path.join(buildFolder, 'package.json')))) {
-      fs.symlinkSync(path.resolve('package.json'), path.resolve(path.join(buildFolder, 'package.json')), 'file')
+    if (!fs.existsSync(outPkgPath)) {
+      await this.linkOrCopy(path.resolve('package.json'), outPkgPath, 'file')
     }
 
     // include any "extras" from the "include" section
@@ -209,6 +212,23 @@ export class TypeScriptPlugin {
     fs.removeSync(path.join(this.originalServicePath, buildFolder))
   }
 
+  /**
+   * Attempt to symlink a given path or directory and copy if it fails with an
+   * `EPERM` error.
+   */
+  private async linkOrCopy(
+    srcPath: string,
+    dstPath: string,
+    type?: 'dir' | 'junction' | 'file'
+  ): Promise<void> {
+    return fs.symlink(srcPath, dstPath, type)
+      .catch(error => {
+        if (error.code === 'EPERM' && error.errno === -4048) {
+          return fs.copy(srcPath, dstPath)
+        }
+        throw error
+      })
+  }
 }
 
 module.exports = TypeScriptPlugin

yarn.lock

@@ -2974,7 +2974,7 @@ ret@~0.1.10:
   resolved "https://registry.yarnpkg.com/ret/-/ret-0.1.15.tgz#b8a4825d5bdb1fc3f6f53c2bc33f81388681c7bc"
   integrity sha512-TTlYpa+OL+vMMNG24xSlQGEJ3B/RzEfUlLct7b5G/ytav+wPrplCpVMFuwzXbkecJrb6IYo1iFb0S9v37754mg==
 
-rimraf@^2.5.4, rimraf@^2.6.2:
+rimraf@^2.5.4, rimraf@^2.6.2, rimraf@^2.6.3:
   version "2.6.3"
   resolved "https://registry.yarnpkg.com/rimraf/-/rimraf-2.6.3.tgz#b2d104fe0d8fb27cf9e0a1cda8262dd3833c6cab"
   integrity sha512-mwqeW5XsA2qAejG46gYdENaxXjx9onRNCfn7L0duuP4hCuTIi/QO7PDK07KJfp1d+izWPrzEJDcSqBa0OZQriA==