Create a custom Link to a File-Field in Twig I'm trying to customize a download-link for a file-field in my entity. 
In a similar setup, i was able to customize a link-field in the following way:

&lt;a href="{{ node.field_publication_link.uri }}"&gt; Link &lt;/a&gt;


So, for the file-field, i tried something similar:

&lt;a href="{{ node.field_publication_file.0.uri }}"&gt; Download &lt;/a&gt;


However, there is no such thing as a uri field available. I have a hard time figuring out which fields actually are available for me to use in the template. I found kint to be way too noisy, i had to restrict memory consumption and still have no clue which fields are usable.

Alternatively, i tried to create a custom template for the specific file field, called field--field-publication-file.html.twig. The debug info tells me that it is used for rendering. 
I had a look at the field that my theme (bootstrap) normally uses and tried to mimick its behavior. Specifically, i wanted to use the field link, which is also used in the bootstrap version. However, this field is always empty when using my version.

What more could i try?
After more research, i found the answer by accident on this page. One can refer to the link by using: 

&lt;a href="{{ file_url (node.field_publication_file.entity.uri.value) }}"&gt; 
  Download
&lt;/a&gt;


The fields that were defined in the bootstrap theme don't seem to be accessible in a sub-theme of bootstrap. I'm sure I could have written a custom preprocessor to do the same thing, but this solution works for me and I don't have to write PHP code.