dernasherbrezon / fingerprint-maven-plugin Goto Github PK

It would be great if there was a method of mapping URLs to the filesystem. For instance if my app has a prefix (like /apps) this plugin won't work by default because the URLs in the HTML won't line up with the file system structure. Something like the following could be useful:

<img src="/apps/app1/logo.png">

and my directory structure looks like this:

src/main/webapp/app1/logo.png

then set the following map in the pom.xml:

<urlMappings>
    <urlMapping>
        <urlPrefix>/apps/</urlPrefix>
        <fsPath>/</fsPath>
    </urlMapping>
</urlMappings>

The outcome would be a straightforward find/replace with the mappings. So /apps/app1/logo.png would map to /app1/logo.png on the file system.

Let's say your project consists of these files:

• index.html references stylesheet.css
• stylesheet.css references background.png
• background.png

Running the plugin once works as expected:

1. The image gets renamed according to its hash, and the reference to it in the CSS file is changed as well.
2. The CSS file gets renamed according to its hash, and the reference to it in the HTML file is changed as well.

Now you replace/edit the image file and run the plugin again:

1. The image gets renamed according to its new hash, and the reference to it in the CSS file is also changed.
2. However, the CSS file is not renamed compared to the previous situation!

It turns out that the plugin uses the hashes of the original source file's contents. But we did not change the source CSS at all - it still references background.png!

The result is that in the HTML file, the reference to the CSS still has the same hash as before. Therefore, browsers will not reload the CSS, and will therefore not reload the image file!

This problem could be prevented if the plugin calculated the hashes of the modified files, i.e. after it altered the contained references to other resources.

Workaround: do not use any image URLs in CSS. 😢