Introduce before_request configuration (shakacode#138)

Author: RomainEndelin

CHANGELOG.md

@@ -1,3 +1,6 @@
+### Added
+* Add support for `before_request` options on the middleware, for authentication [PR 138](https://github.com/shakacode/cypress-on-rails/pull/138) by [RomainEndelin]
+
 ## [1.15.1]
 [Compare]: https://github.com/shakacode/cypress-on-rails/compare/v1.15.0...v1.15.1
 

README.md

@@ -395,6 +395,47 @@ describe('My First Test', () => {
 })
 ```
 
+## `before_request` configuration
+
+You may perform any custom action before running a CypressOnRails command, such as authentication, or sending metrics.  Please set `before_request` as part of the CypressOnRails configuration.
+
+You should get familiar with [Rack middlewares](https://www.rubyguides.com/2018/09/rack-middleware/).
+If your function returns a `[status, header, body]` response, CypressOnRails will halt, and your command will not be executed. To execute the command, `before_request` should return `nil`.
+
+### Authenticate CypressOnRails
+
+```ruby
+  CypressOnRails.configure do |c|
+    # ...
+
+    # Refer to https://www.rubydoc.info/gems/rack/Rack/Request for the `request` argument.
+    c.before_request = lambda { |request|
+      body = JSON.parse(request.body.string)
+      if body['cypress_token'] != ENV.fetch('SWEEP_CYPRESS_SECRET_TOKEN')
+        # You may also use warden for authentication:
+        #   if !request.env['warden'].authenticate(:secret_key)
+        return [401, {}, ['unauthorized']]
+      end
+
+    }
+  end
+```
+
+### Send usage metrics
+
+```ruby
+  CypressOnRails.configure do |c|
+    # ...
+
+    # Refer to https://www.rubydoc.info/gems/rack/Rack/Request for the `request` argument.
+    c.before_request = lambda { |request|
+      statsd = Datadog::Statsd.new('localhost', 8125)
+
+      statsd.increment('cypress_on_rails.requests')
+    }
+  end
+```
+
 ## Usage with other rack applications
 
 Add CypressOnRails to your config.ru

lib/cypress_on_rails/configuration.rb

@@ -6,6 +6,7 @@ class Configuration
     attr_accessor :install_folder
     attr_accessor :use_middleware
     attr_accessor :use_vcr_middleware
+    attr_accessor :before_request
     attr_accessor :logger
 
     # Attributes for backwards compatibility
@@ -30,6 +31,7 @@ def reset
       self.install_folder = 'spec/e2e'
       self.use_middleware = true
       self.use_vcr_middleware = false
+      self.before_request = -> (request) {}
       self.logger = Logger.new(STDOUT)
     end
 

lib/cypress_on_rails/middleware.rb

@@ -47,6 +47,10 @@ def file_path
     end
 
     def handle_command(req)
+      maybe_env = configuration.before_request.call(req)
+      # Halt the middleware if an Rack Env was returned by `before_request`
+      return maybe_env unless maybe_env.nil?
+
       body = JSON.parse(req.body.read)
       logger.info "handle_command: #{body}"
       commands = Command.from_body(body, configuration)

lib/generators/cypress_on_rails/templates/config/initializers/cypress_on_rails.rb.erb

@@ -7,6 +7,15 @@ if defined?(CypressOnRails)
     c.use_middleware = !Rails.env.production?
     <% unless options.experimental %># <% end %> c.use_vcr_middleware = !Rails.env.production?
     c.logger = Rails.logger
+
+    # If you want to enable a before_request logic, such as authentication, logging, sending metrics, etc.
+    #   Refer to https://www.rubydoc.info/gems/rack/Rack/Request for the `request` argument.
+    #   Return nil to continue through the Cypress command. Return a response [status, header, body] to halt.
+    # c.before_request = lambda { |request|
+    #   unless request.env['warden'].authenticate(:secret_key)
+    #     return [403, {}, ["forbidden"]]
+    #   end
+    # }
   end
 
   # # if you compile your asssets on CI

spec/cypress_on_rails/configuration_spec.rb

@@ -8,19 +8,23 @@
     expect(CypressOnRails.configuration.install_folder).to eq('spec/e2e')
     expect(CypressOnRails.configuration.use_middleware?).to eq(true)
     expect(CypressOnRails.configuration.logger).to_not be_nil
+    expect(CypressOnRails.configuration.before_request).to_not be_nil
   end
 
   it 'can be configured' do
     my_logger = Logger.new(STDOUT)
+    before_request_lambda = -> (_) { return [200, {}, ['hello world']] }
     CypressOnRails.configure do |config|
       config.api_prefix = '/api'
       config.install_folder = 'my/path'
       config.use_middleware = false
       config.logger = my_logger
+      config.before_request = before_request_lambda
     end
     expect(CypressOnRails.configuration.api_prefix).to eq('/api')
     expect(CypressOnRails.configuration.install_folder).to eq('my/path')
     expect(CypressOnRails.configuration.use_middleware?).to eq(false)
     expect(CypressOnRails.configuration.logger).to eq(my_logger)
+    expect(CypressOnRails.configuration.before_request).to eq(before_request_lambda)
   end
 end