Date Math / Manipulation in Liquid Template Filter
date, liquid, liquid-layout, shopify
Solution
Much thanks to @iveskev from the Desk.com "WOW" team for this answer:
If you do `{{'now'}}` it returns the string “now” not a timestamp for the current time. So if you do `{{'now' | minus: 604800 }}` it returns “-604800” not the current unix time minus 604800. When you use the `date` filter, then liquid picks up that you are referencing the current time and outputs the time as a string. However even if we get ‘now’ to output the current date, we are still subtracting from a string and so will be returned with “-604800”. The only time that math on a string works correctly is if the sting is only a number.
So in order to get the correct date we first have to get the unix timestamp for now, do the subtraction, then reformat to the desired formate. You can use `%s` to get unix time. So to get the current time in unix it would be: `{{'now' | date: '%s' }}`
At that point you can then do the subtraction and then format the time in the correct way. We can do this all at once in the following statement:
`{{'now' | date: "%s" | minus : 604800 | date: "%b %d, %Y %I:%M %p -0500" | uri_encode | replace:"+","%20"}}`
Problem
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. 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. For the current time, this syntax is valid and working: ``` {{'now' | date: "%b %d, %Y %I:%M %p -0500" | uri_encode | replace:"+","%20"}} ``` For 7 days ago, here's the best I could come up with (isn't working): ``` {{'now' | minus : 604800 | date: "%b %d, %Y %I:%M %p -0500" | uri_encode | replace:"+","%20"}} ``` Any suggestions on a valid syntax for "7 days ago" in Liquid? Would greatly appreciate any advice!