Dynamic URLs Guide

fastn can be used for creating dynamic websites. By default fastn maps the URL’s path to file system to decide which ftd document to serve. This behaviour can be changed as described in custom URLs guide. In this guide we will see how we can map any URL matching a given pattern to a ftd document.

Dynamic URLs are specified in FASTN.ftd file under the fastn.dynamic-urls section:
-- fastn.dynamic-urls:

# User Profile Page
  url: /<string:username>/
  document: profile.ftd
In the above snippet we are saying any URL that matches the pattern /<string:username>/ will be served by the document profile.ftd. When this url matches, the matching value of the string is stored as username and can be extracted using request-data processor.
-- import: fastn/processors as pr

-- record r-data:
string username:

-- r-data data:
$processor$: pr.request-data

-- ds.markdown: $data.message

Valid Types

Following types are supported:


This matches any string other than /.


This matches any valid integer.


This matches any decimal number.

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