title: Date Math / Manipulation in Liquid Template Filter
body: <p>I'm constructing an "Integration URL" in Desk.com, which uses the Shopify Liquid Template filter syntax. This URL needs to contain a "start date" and an "end date" for a query where the start date is 7 days ago and the end date is right now.</p>
  
  <p>To achieve this I think I need to subtract 7 days (604800 in Epoch time) from the 'now' object and then apply my formatting but I can't figure out valid syntax for that.</p>
  
  <p>For the current time, this syntax is valid and working: </p>
  
  <pre><code>{{'now' | date: "%b %d, %Y %I:%M %p -0500" | uri_encode | replace:"+","%20"}}
  </code></pre>
  
  <p>For 7 days ago, here's the best I could come up with (isn't working): </p>
  
  <pre><code>{{'now' | minus : 604800 | date: "%b %d, %Y %I:%M %p -0500" | uri_encode | replace:"+","%20"}}
  </code></pre>
  
  <p>Any suggestions on a valid syntax for "7 days ago" in Liquid? Would greatly appreciate any advice!</p>