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herokuseocanonical-link

How to specify canonical link in app on heroku when another domain points to it


With a domain pointing to an app on Heroku, I want to set the canonical link to the main domain, not the Heroku url, when the current url is the Heroku url, and not the domain..

How do I do that and not have the canonical link there when someone goes to the site at the main domain url?


Solution

  • You can use one of

    ENV['HTTP_HOST']
    ENV['SERVER_NAME']
    ENV['DOCUMENT_ROOT']
    

    to check whether the site is your main server and if not, print out the canonical URL.

    You can also take a look at the ENV variable by dumping it out for more info:

    <%= h ENV.inspect %>