Accessing the Request Object in Sinatra

Accessing the request object

Sinatra offers some incoming request objects which can be accessed from the request level, i.e., filter, error handlers, etc., through the request method option:

get '/foo' do
  t = %w[text/css text/html application/javascript]
  request.accept
  request.accept? 'text/xml'
  request.preferred_type(t)
  request.body
  request.scheme
  request.script_name
  request.path_info
  request.port
  request.request_method
  request.query_string
  request.content_length
  request.media_type
  request.host
  request.get?
  request.form_data?
  request["some_param"]
  request.referrer
  request.user_agent
  request.cookies
  request.xhr?
  request.url
  request.path
  request.ip
  request.secure?
  request.forwarded?
  request.env
end

Sinatra offers some other options, i.e., script_name, path_info, etc., which can be used as follows:

before { request.path_info = "/" }

get "/" do
  "END"
end

The request.body is a StringIO object:

post "/api" do
  request.body.rewind
  data = JSON.parse request.body.read
  "Hello!"
end

Attachments

Sinatra offers a syntax attachment that tells the browser or custom tabs that the response should be stored somewhere in the disk rather than displayed in the browser:

get '/' do
  attachment
  "Store it somewhere."
end

We can also pass the file name where to store the attachment.

get '/' do
  Attachment “store.txt”
  "Store it somewhere."
end

Output Examples

attachment -> we parse string which its store on the given file.

get '/' do
  Attachment “store.txt”
  "Store it somewhere."
end

It stores "Store it somewhere." in the file with a name store.txt

Frequently Asked Questions

How does Sinatra function?

The web server responds to a series of queries that Sinatra sends and receives. These requests are contained in a controller file, which is part of your program and communicates with the internet. A controller is a component of the MVC architectural design pattern (Models-Views-Controllers).

Why should Sinatra always be chosen over Rails?

Sinatra performs fewer functions out of the box and is significantly more lightweight, resource-efficient, and demanding. Rails are crammed with features and come with a tonne of code, and if you know how to use it, it makes it very simple to construct complex web applications quickly.

What is Rack middleware?

You can allude rack middleware as a bit of part that helps with the execution of an undertaking. For instance, You can imagine different middleware doing various cycles like logging and reserving.

Is Flask similar to Sinatra?

Sinatra is ideal for basic apps, much like Flask. Only 4 LOC of the actual Sinatra application is contained in a single Ruby source file, due to which Flask is used instead of libraries like Ruby on Rails. Sinatra is used since it allows you to start small and grow the application as necessary.

What exactly are Rails and Sinatra?

Rail is a framework for creating model-driven web applications, while Sinatra is a library for handling HTTP on the server side. Sinatra is an excellent tool for handling HTTP requests and responses. Rails are the way to go if you need full integration and as little boilerplate as possible.

Conclusion

In this article, we have learned how to access the request object in Sinatra. I hope you would have gained a better understanding of these topics now!

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