如何在Heroku的postinstall阶段编译TypeScript？

Got it, let's walk through this together. You want to skip pushing your precompiled dist folder and build your src directly on Heroku—totally reasonable, and you're right that npm install adds node_modules/.bin to the PATH during setup. Let's break down the most common fixes for the build errors you're seeing:

1. Double-Check Your package.json Scripts & Dependencies #

First, make sure your build command is properly defined, and all required tools are installed correctly.

• Build Script: You need a build script that tells Heroku exactly how to compile src into dist. For example:

  {
    "scripts": {
      "build": "webpack --mode production", // Webpack example
      "start": "node server.js"
    }
  }
  

  Test this script locally first with npm run build—if it fails on your machine, it will definitely fail on Heroku too.
• Dependency Placement: If your build tools (like webpack, babel, or vue-cli) are in devDependencies, Heroku will skip installing them by default in production mode. Fix this either:
  • Move those build tools to dependencies, or
  • Set the environment variable NPM_CONFIG_PRODUCTION=false on Heroku (run heroku config:set NPM_CONFIG_PRODUCTION=false in your terminal) to force installation of dev dependencies during the build.

2. Dig Into Heroku's Build Logs #

The error message you're getting holds the key—run heroku logs --tail in your terminal to see the full, real-time build output. Common red flags to look for:

• "Command not found" errors: This usually means the build tool isn't installed (double-check the dependency step above).
• Missing files: If Heroku complains about missing src files or configs (like webpack.config.js), verify your .gitignore isn't excluding critical build assets.
• Version mismatches: Heroku might be using a different Node/npm version than your local machine. Add an engines field to package.json to lock versions:

  {
    "engines": {
      "node": "18.x",
      "npm": "9.x"
    }
  }
  

3. Verify Heroku's Build Process Triggers Correctly #

Heroku automatically runs npm run build for Node.js apps, but only if it detects a valid Node project. If your app uses a custom setup, you might need to:

• Add a Procfile if your start command isn't the default npm start, or
• Use a Heroku buildpack tailored to your framework (like the official Node.js buildpack) to ensure proper build handling.

4. Ensure Your src Directory Is Pushed to Git #

Double-check that your src folder isn't listed in .gitignore—if it is, Heroku won't pull it down, so it can't compile anything at all.

If you can share the specific error message from your logs or your full package.json scripts/dependencies, I can give you even more targeted help!

内容的提问来源于stack exchange，提问作者Talha Talip Açıkgöz