Environments in Sinatra

Deploy your application. 

Make a source bundle with your source files in it. The command below generates a source bundle called Sinatra-default.zip.

~/eb-sinatra$ zip ../Sinatra-default.zip -r * .[^.]*

To deploy Sinatra in your environment, upload the source bundle to Elastic Beanstalk. 

To install a source bundle 

• Select your Amazon Region from the Regions list in the Elastic Beanstalk console. 
• Choose Environments from the navigation pane, and then select the name of your environment from the list. 

Note: If you have a lot of environments, use the search bar to narrow down the list. 

• Select Upload and deploy from the environment overview page. 
• Upload the source bundle using the on-screen dialogue box. 
• Select Deploy. 
• When the deployment is finished, you can open your website in a new tab by selecting the site URL.

Environments 

There are three environments available: "development," "production," and "test." The APP ENV environment variable can be used to configure environments. The default setting is "development." All templates are reloaded between requests in the "development" environment, and special not found and error handlers display stack traces in your browser. Templates are cached by default in the "production" and "test" environments. 

Set the APP ENV environment variable to run different environments: 

APP_ENV=production ruby my_app.rb

To check the current environment setting, you can use predefined methods: development? test?, and production?

get '/' do
  if settings.development?
    "development!"
  else
    "not development!"
  end
end

Error handlers run in the same context as routes and before filters, so you get all the goodies it has to offer, such as haml, erb, halt, and so on.

Not able to Found

When a Sinatra::NotFound exception is thrown, or the status code of the response is 404, the not found handler is called: 

not_found do
  'This is nowhere to be found.'
end

Error 

When a route block or a filter raises an exception, the error handler is called. However, in development, it will only run if the show exceptions option is set to: after handler:

set :show_exceptions, :after_handler.

The exception object is accessible via the Sinatra.error Rack variable:

error do 
'Error Found -'+ env['sinatra.error']. 

message
end

Errors in customization: 

error MyCustomError do
  'Kind of ' + env['sinatra.error'] . message
end

Then, if this occurs: 

get '/' do
  raise MyCustomError, 'bad'
end

You will receive the following: 

Kind of bad

You can also install an error handler for a status code: 

error 403 do
  'Access forbidden'
end

get '/secret' do
  403
end

Range of:

error 400..510 do
  'Boom'
end

Frequently Asked Questions

Why should you always use Sinatra over rails? 

Sinatra is much lighter, requires fewer resources, and does fewer things out of the box. Rails, on the other hand, is jam-packed with features, comes with a tonne of code, and makes it very simple to build complex web applications in a short period of time if you know how to use it.

What exactly is Rack middleware? 

Rack middleware is a method of filtering requests and responses that come into your application. A middleware component sits between the client and the server, processing inbound, and outbound requests and responses. Still, it is more than just an interface that can communicate with the web server.

What exactly is config ru? 

Rack configuration file config.ru ( ru stands for "rackup"). Rack is a simple interface that connects web servers that support Ruby and Ruby frameworks. It's similar to a Ruby implementation of a CGI, which provides a standard protocol for web servers to use when running programs.

Describe Ruby rack.

Ruby programmers created Rack, a modular interface between web servers and web applications. Application programming interfaces (APIs) for middleware and web frameworks are encapsulated in a single method call for HTTP requests and responses using Rack.

Ruby Webserver Interface called Rack.

Rails with Sinatra: what is it?

Sinatra is a server-side HTTP library, whereas Rails is a framework for developing model-driven web applications. Sinatra is the best tool if you think in terms of HTTP requests and responses. Rails are the way to go if you require complete integration and as little boilerplate as possible.

Conclusion

This article has gone through the Environment in Sinatra. Understand the Elastic Beanstalk environment. Also deployed our application and last understand the concept of Error handling. I suppose it is clear to you. Still, have doubt? Then please comment.

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