Fingerprinting & Manifest

faucet-pipeline can fingerprint the generated files for you. That means that it adds a hash of the file content to the file name. This allows you to cache your files indefinitely to reduce the number of requests your clients need to make. To enable that, pass the --fingerprint option to the CLI.

When you fingerprint your files, you can no longer hard code the URIs in your HTML as well as CSS. You need to have a way to look up the resulting URIs. faucet-pipeline can generate a so called manifest file for that purpose (see configuration below for how to enable it): The key is is an identifier for you to find the file. The value is the URL where the files will be available.

The manifest could look like this:

    "output/example.css": "/assets/example-123.css"

The idea is that in your Web app you provide a helper that is provided with the key and will return the value. You can then use it in your template engine so that you can access the fingerprinted path. For existing integrations, see the navigation.

For your Sass files, faucet-pipeline-sass automatically reads the manifest to give you access to the static files like files and images. See Sass for details on that.


The generation of the manifest ist activated when you put the manifest key in your configuration with an object at least containing a file option with a path to where you want your manifest to go.

module.exports = {
    manifest: {
        target: "./path/to/manifest.json"

By default, the generated manifest will haveā€¦

If you want a shorter key, you can set key to "short". They key will now be relative to the respective target for each entry. In the case of a single file that means you will only have the file name as the key. In the case of a directory of files, the key will be relative to that directory.

You can also adjust the value: You can provide a baseURI to use something other than /. You can provide a webRoot as a relative path to generate the value relative to a different folder (in some frameworks that would be ./public, the folder that is used to serve static files).


module.exports = {
    manifest: {
        target: "./path/to/manifest.json",
        key: "short",
        baseURI: "/assets/",
        webRoot: "./target"

Advanced Configuration

You can manipulate both the key and the value with a function (you can provide none, one or both):

The key function receives the path to the generated file without the fingerprint relative to your configuration file and the target directory as its input (Example: "public/images/background/example.jpg" and "public/images"). The return value will be used as the key.

The value function receives the path to the generated file with the fingerprint relative to your configuration file as its input (Example: "public/images/background/example-12345.jpg" and "public/images"). The return value will be used as the value.

The target directory is the target in the case of faucet-pipeline-static, and the dirname of the target in the case of faucet-pipeline-js and faucet-pipeline-sass.