Download Transformer

Download Transformer is a simple asset transformer that fetches files over HTTPS at compile time. Ideal for managing large assets without checking them into source control or sharing assets with non-programmers. It works on all platforms at compile-time, but since you only build the app from Desktop, only those are listed as platforms.

Installation

Add download_transformer to your dev_dependencies in pubspec.yaml:

dev_dependencies:
  download_transformer: ^1.0.3

Usage

  1. Create an empty placeholder

    In your assets folder, add an empty file named after the target asset, e.g., texture_sample.png.

  2. Specify the download URL

    Open the file and insert the asset URL on a single line, for example: https://dekeyser.ch/texture_sample.png

  3. Configure the transformer

    Reference the placeholder in your pubspec.yaml and attach the transformer. You can also transform assets of entire folders:

    flutter:
  assets:
    - path: assets/texture_sample.png
      transformers:
        - package: download_transformer
    - path: assets/folder_with_many_assets/
      transformers:
        - package: download_transformer

  4. Build your project

    During compilation, the transformer replaces the placeholder with the downloaded asset.

That’s it! No more checked-in binaries—just maintain URLs and let the build process fetch your assets automatically.

Libraries