Copying missing files during a typescript build on deploy

If you build your nodeJS project using typescript, it's important to know that the typescript compiler tsc will only include files that are .js or .ts.

If you have an issue where you deploy or build a typescript project and you get a file not found issue or similar, it's probably because you missed that typescript does not process these kinds of files for you.

If you need to include files like XML (.xml) or images in your typescript project build output, you will have to copy them manually before or after the build process.

This is one way to copy assets in a typescript build.

1. Install copyfiles

copyfiles is an npm package so install it using your favorite package manager

yarn install -D copyfiles

# or

npm install --save-dev copyfiles

2. Add a copy files script

Add a script to your package.json file to copy the files you need. There are many options for copy files so check out their documentation, but this is what I typically use.

You can see here that I also have a "build" script that will be called to build the application.

I assume you will output the typescript build to build folder but this will be unique for your project. The last option in the "copyMySpecialFiles" script should match where you want the files to go!

{
  "scripts": {
    "build": "tsc -outDir build",
    "copyMySpecialFiles": "copyfiles --error --up 1 src/the-path/to-my/special-files/*.* build"
  }
}

I'm adding the script copyMySpecialFiles. This copies all the files in the folder to build. The --up 1 tells copyfiles not to include the folder path when it copies. --error fails when there is an error. This is important to highlight unexpected issues when copying by stopping your build.

2. Add a post build script

Here i'm adding a special postbuild script. This script will automatically be run by tsc when the typescript build is successful. You don't have to explicitly call this anywhere. If postbuild exists, tsc will call it for you.

{
  "scripts": {
    "build": "tsc -o build",
    "copyMySpecialFiles": "copyfiles --error --up 1 src/the-path/to-my/special-files/*.* build",
    "postbuild": "yarn run copyMySpecialFiles"
  }
}

And that's it! you can use this to copy any required pdfs, images, excel files etc to the build output for you typescript Node.js application.