Turn your apps to maintenance mode using environment variables

If there is planned maintenance, a site must go into maintenance mode and the end-user should be made aware of the event. A notice something like - Our site is under maintenance, please come back after some time should be conveyed. To avoid hardcoding the site routes every time it goes under maintenance, environment variables can be employed.

For rails apps

Set an environment variable as MAINTENANCE = true in cloud66.
Check for this variable in the routes file of your application for redirecting to the a /maintenance page. Examples:

Note: Always place your maintenance page routes at the top of all other routes

For a monolith application

if ENV["MAINTENANCE"] == true
    get '/', to: redirect('/maintenance_page'), via: :get
    get '/maintenance_page', to: 'application#maintenance_page'
    get '*path', to: redirect('/maintenance_page'), via: :get
end

Create an action inside application_controller.rb example,

def maintenance_page

end

Then create a template under views/application/maintenance_page.html

For an API the routes should be

if ENV["MAINTENANCE"] == true
    get '/', to: 'application#maintenance_page', via: :get
    get '*path', to: 'application#maintenance_page', via: :get
    post '/', to: 'application#maintenance_page', via: :post
    post '*path', to: 'application#maintenance_page', via: :post
end

def maintenance_page
    render json: { error: "Under Maintenance Site will be back in few hours"}, status: 503
end

The status code 503 will allow a front-end client to understand the application is under maintenance and they can convey it to the user.

Example template in a monolith app.

 <div style="position: absolute; top: 50%; left: 50%; transform: translate(-50%,-50%); text-align: center;">
     <div>
         <img src="/w3images/forestbridge.jpg" />
     </div>
     <p style="text-transform: none; color: #31383D; font-weight: bold; font-size: 36px; padding: 20px 20px 0px 20px; line-height: 49px;">
         <br />
         Sorry, our site is under maintenance.
     </p>
     <p style="color: #31383d; font-family: &#39;Source Sans Pro&#39;; font-size: 18px; padding: 20px; line-height: 28px;">
         Thank you for being patient. You can get back to our site in a few hours.
         <br />
         Contact us on
         <a href="mailto:info@address.in" style="color:blue"> info@address.in </a> for any queries.
     </p>
  </div>

An industry-standard practice is to keep the maintenance page color scheme and design consistent with your application.

Maintenance ENV

Turn your apps to maintenance mode using environment variables

For rails apps