How to solve error “Missing `secret_key_base` for

问题:

I've created a rails app (rails 4.1) from scratch and I am facing a strange problem that I am not able to solve.

Every time I try to deploy my app on Heroku I get an error 500:

Missing secret_key_base for 'production' environment, set this value in config/secrets.yml

The secret.yml file contains the following configuration:

secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>

On Heroku I have configured an environment variable "SECRET_KEY_BASE" with the result of "rake secret" command. If I launch "heroku config", I can see the variable with the correct name and value.

Why am I still getting this error?

Thanks a lot

回答1:

I had the same problem and I solved it by creating an environment variable to be loaded every time that I logged in to the production server and made a mini guide of the steps to configure it:

https://gist.github.com/pablosalgadom/4d75f30517edc6230a67

I was using Rails 4.1 with Unicorn v4.8.2, when I tried to deploy my app it didn't start properly and in the unicorn.log file I found this error message:

app error: Missing `secret_key_base` for 'production' environment, set this value in `config/secrets.yml` (RuntimeError)

After some research I found out that Rails 4.1 changed the way to manage the secret_key, so if you read the secrets.yml file located at exampleRailsProject/config/secrets.yml you'll find something like this:

# Do not keep production secrets in the repository,
# instead read values from the environment.
production:
  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>

This means that Rails recommends you to use an environment variable for the secret_key_base in your production server, in order to solve this error you should follow this steps to create an environment variable for Linux (in my case Ubuntu) in your production server:

1. In the terminal of your production server execute the next command:

   $ RAILS_ENV=production rake secret
   

   This returns a large string with letters and numbers, copy that (we will refer to that code as GENERATED_CODE).

2. Login to your server

   • If you login as the root user, find this file and edit it:

     $ vi /etc/profile
     

     Go to the bottom of the file ("SHIFT + G" for capital G in VI)

     Write your environment variable with the GENERATED_CODE (Press "i" key to write in VI), be sure to be in a new line at the end of the file:

     $ export SECRET_KEY_BASE=GENERATED_CODE
     

     Save the changes and close the file (we push "ESC" key and then write ":x" and "ENTER" key for save and exit in VI).

   • But if you login as normal user, lets call it "example_user" for this gist, you will need to find one of this other files:

     $ vi ~/.bash_profile
     $ vi ~/.bash_login
     $ vi ~/.profile
     

     These files are in order of importance, that means that if you have the first file, then you wouldn't need to write in the others. So if you found this 2 files in your directory ~/.bash_profile and ~/.profile you only will have to write in the first one ~/.bash_profile, because Linux will read only this one and the other will be ignored.

     Then we go to the bottom of the file ("SHIFT + G" for capital G in VI).

     And we will write our environment variable with our GENERATED_CODE (Press "i" key to write in VI), be sure to be in a new line at the end of the file:

     $ export SECRET_KEY_BASE=GENERATED_CODE
     

     Having written the code, save the changes and close the file (we push "ESC" key and then write ":x" and "ENTER" key for save and exit in VI).

3. You can verify that our environment variable is properly set in Linux with this command:

   $ printenv | grep SECRET_KEY_BASE
   

   or with:

   $ echo $SECRET_KEY_BASE
   

   When you execute this command, if everything went ok, it will show you the GENERATED_CODE from before. Finally with all the configuration done you should be able to deploy without problems your Rails app with Unicorn or other.

When you close your shell terminal and login again to the production server you will have this environment variable set and ready to use it.

And thats it!! I hope this mini guide help you to solve this error.

Disclaimer: I'm not a Linux or Rails guru, so if you find something wrong or any error I will be glad to fix it!

回答2:

I'm going to assume that you do not have your secrets.yml checked into source control (ie. it's in the .gitignore file). Even if this isn't your situation, it's what many other people viewing this question have done because they have their code exposed on Github and don't want their secret key floating around.

If it's not in source control, Heroku doesn't know about it. So Rails is looking for Rails.application.secrets.secret_key_base and it hasn't been set because Rails sets it by checking the secrets.yml file which doesn't exist. The simple workaround is to go into your config/environments/production.rb file and add the following line:

Rails.application.configure do
    ...
    config.secret_key_base = ENV["SECRET_KEY_BASE"]
    ...
end

This tells your application to set the secret key using the environment variable instead of looking for it in secrets.yml. It would have saved me a lot of time to know this up front.

回答3:

Add config/secrets.yml to version control and deploy again. You might need to remove a line from .gitignore so that you can commit the file.

I had this exact same issue and it just turned out that the boilerplate .gitignore Github created for my Rails application included config/secrets.yml.

回答4:

This worked for me.

SSH into your production server and cd into your current directory, run bundle exec rake secret or rake secret, you will get a long string as an output, copy that string.

Now run sudo nano /etc/environment.

Paste at the bottom of the file

export SECRET_KEY_BASE=rake secret
ruby -e 'p ENV["SECRET_KEY_BASE"]'

Where rake secret is the string you just copied, paste that copied string in place of rake secret.

Restart the server and test by running echo $SECRET_KEY_BASE.

回答5:

While you can use initializers like the other answers, the conventional Rails 4.1+ way is to use the config/secrets.yml. The reason for the Rails team to introduce this is beyond the scope of this answer but the TL;DR is that secret_token.rb conflates configuration and code as well as being a security risk since the token is checked into source control history and the only system that needs to know the production secret token is the production infrastructure.

You should add this file to .gitignore much like you wouldn't add config/database.yml to source control either.

Referencing Heroku's own code for setting up config/database.yml from DATABASE_URL in their Buildpack for Ruby, I ended up forking their repo and modified it to create config/secrets.yml from SECRETS_KEY_BASE environment variable.

Since this feature was introduced in Rails 4.1, I felt it was appropriate to edit ./lib/language_pack/rails41.rb and add this functionality.

The following is the snippet from the modified buildpack I created at my company:

class LanguagePack::Rails41 < LanguagePack::Rails4

  # ...

  def compile
    instrument "rails41.compile" do
      super
      allow_git do
        create_secrets_yml
      end
    end
  end

  # ...

  # writes ERB based secrets.yml for Rails 4.1+
  def create_secrets_yml
    instrument 'ruby.create_secrets_yml' do
      log("create_secrets_yml") do
        return unless File.directory?("config")
        topic("Writing config/secrets.yml to read from SECRET_KEY_BASE")
        File.open("config/secrets.yml", "w") do |file|
          file.puts <<-SECRETS_YML
<%
raise "No RACK_ENV or RAILS_ENV found" unless ENV["RAILS_ENV"] || ENV["RACK_ENV"]
%>

<%= ENV["RAILS_ENV"] || ENV["RACK_ENV"] %>:
  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
          SECRETS_YML
        end
      end
    end
  end

  # ...

end

You can of course extend this code to add other secrets (e.g. third party API keys, etc.) to be read off of your environment variable:

...
<%= ENV["RAILS_ENV"] || ENV["RACK_ENV"] %>:
  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
  third_party_api_key: <%= ENV["THIRD_PARTY_API"] %>

This way, you can access this secret in a very standard way:

Rails.application.secrets.third_party_api_key

Before redeploying your app, be sure to set your environment variable first:

Then add your modified buildpack (or you're more than welcome to link to mine) to your Heroku app (see Heroku's documentation) and redeploy your app.

The buildpack will automatically create your config/secrets.yml from your environment variable as part of the dyno build process every time you git push to Heroku.

EDIT: Heroku's own documentation suggests creating config/secrets.yml to read from the environment variable but this implies you should check this file into source control. In my case, this doesn't work well since I have hardcoded secrets for development and testing environments that I'd rather not check in.

回答6:

You can export the secret keys to as environment variables on the ~/.bashrc or ~/.bash_profile of your server:

export SECRET_KEY_BASE = "YOUR_SECRET_KEY"

And then, you can source your .bashrc or .bash_profile:

source ~/.bashrc 
source ~/.bash_profile

Never commit your secrets.yml

回答7:

What I did : On my production server, I create a config file (confthin.yml) for Thin (I'm using it) and add the following information :

environment: production
user: www-data
group: www-data
SECRET_KEY_BASE: mysecretkeyproduction

I then launch the app with

thin start -C /whereeveristhefieonprod/configthin.yml

Work like a charm and then no need to have the secret key on version control

Hope it could help, but I'm sure the same thing could be done with Unicorn and others.

回答8:

I have a patch that I've used in a Rails 4.1 app to let me continue using the legacy key generator (and hence backwards session compatibility with Rails 3), by allowing the secret_key_base to be blank.

Rails::Application.class_eval do
  # the key_generator will then use ActiveSupport::LegacyKeyGenerator.new(config.secret_token)
  fail "I'm sorry, Dave, there's no :validate_secret_key_config!" unless instance_method(:validate_secret_key_config!)
  def validate_secret_key_config! #:nodoc:
    config.secret_token = secrets.secret_token
    if config.secret_token.blank?
      raise "Missing `secret_token` for '#{Rails.env}' environment, set this value in `config/secrets.yml`"
    end 
  end 
end

I've since reformatted the patch are submitted it to Rails as a Pull Request

回答9:

I've created config/initializers/secret_key.rb file and I wrote only following line of code:

Rails.application.config.secret_key_base = ENV["SECRET_KEY_BASE"]

But I think that solution posted by @Erik Trautman is more elegant ;)

Edit: Oh, and finally I found this advice on Heroku: https://devcenter.heroku.com/changelog-items/426 :)

Enjoy!

回答10:

this is works good https://gist.github.com/pablosalgadom/4d75f30517edc6230a67 for root user should edit

$ /etc/profile

but if you non root should put the generate code in the following

$ ~/.bash_profile

$ ~/.bash_login

$ ~/.profile

回答11:

On Nginx/Passenger/Ruby (2.4)/Rails (5.1.1) nothing else worked except:

passenger_env_var in /etc/nginx/sites-available/default in the server block.

Source: https://www.phusionpassenger.com/library/config/nginx/reference/#passenger_env_var

回答12:

Demi Magus answer worked for me until Rails 5.

On Apache2/Passenger/Ruby (2.4)/Rails (5.1.6), I had to put

export SECRET_KEY_BASE=GENERATED_CODE

from Demi Magus answer in /etc/apache2/envvars, cause /etc/profile seems to be ignored.

Source: https://www.phusionpassenger.com/library/indepth/environment_variables.html#apache

回答13:

I had the same problem after I used the .gitignore file from https://github.com/github/gitignore/blob/master/Rails.gitignore

Everything worked out fine after I commented the following lines in the .gitignore file.

config/initializers/secret_token.rb
config/secrets.yml