discourse/config/initializers/secret_token.rb

# Definitely change this when you deploy to production. Ours is replaced by jenkins.
# This token is used to secure sessions, we don't mind shipping with one to ease test and debug,
#  however, the stock one should never be used in production, people will be able to crack
#  session cookies.
#
# Generate a new secret with "rake secret".  Copy the output of that command and paste it
# in your secret_token.rb as the value of Discourse::Application.config.secret_token:
#
# Discourse::Application.config.secret_token = "SET_SECRET_HERE"

# delete all lines below in production
if Rails.env.test? || Rails.env.development?
  Discourse::Application.config.secret_token = "47f5390004bf6d25bb97083fb98e7cc133ab450ba814dd19638a78282b4ca291"
else
  if Rails.env.production? && ENV['SECRET_TOKEN'].blank?
    raise 'SECRET_TOKEN environment variable must be set!'
  end
  Discourse::Application.config.secret_token = ENV['SECRET_TOKEN']
end