gistfile1.txt

Sinatra accepts a number of different types in the results processing code, and processes/displays them in the following order:

nil
===

If nil is passed to the results, then just the standard Sinatra headers are returned to the client, in the following example

-- test.rb
get "/test/" do
    nil
end

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 200 OK
Content-Type: text/html
Content-Length: 0
Connection: keep-alive
Server: thin 1.0.0 codename That's What She Said

String
======

If a string (responds to to_str) is passed as the results, the standard Sinatra headers are returned to the client with the string (without any further processing) is returned as the body, as shown in the following example

-- test.rb
get "/test/" do
    "This is just a string"
end

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 200 OK
Content-Type: text/html
Content-Length: 21
Connection: keep-alive
Server: thin 1.0.0 codename That's What She Said

This is just a string

Array
=====
Processing of arrays are handled in the following way

1. [Status, (Headers), Body]
The array consists of the numeric HTTP Status code, an optional hash of additional headers to add to the response and the body to return to the client, as shown in the following examples

-- test.rb
get "/test/" do
    [500, "Internal Server Error"]
end

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 500 Internal Server Error
Content-Type: text/html
Content-Length: 21
Connection: keep-alive
Server: thin 1.0.0 codename That's What She Said

Internal Server Error

-- test.rb
get "/test/" do
        [500, {"X-Sung-By" => "Sinatra #{Sinatra::VERSION}"}, "Internal Server Error"]
end

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 500 Internal Server Error
X-Sung-By: Sinatra 0.9.0.5
Content-Type: text/html
Content-Length: 21
Connection: keep-alive
Server: thin 1.0.0 codename That's What She Said

Internal Server Error

Collection
==========

If the result responds to each but doesn't match any of the prior conditions, to_s is called on each member of the collection with the results sent as the body to the client, as shown in the following example using File

-- test.rb
get "/test/" do
        File.open("data.txt","r")
end

-- data.txt
123
456

789
123

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 200 OK
Content-Type: text/html
Connection: close
Server: thin 1.0.0 codename That's What She Said

123
456

789
123

Range
=====

If the result is a number in the range 100 to 599 then the HTTP Status code is set to the result, and no additional headers or body is sent to the client, as shown in the following example

-- test.rb
get "/test/" do
    404
end

-- curl -i http://127.0.0.1:4567/test/
HTTP/1.1 404 Not Found
Content-Type: text/html
Content-Length: 0
Connection: keep-alive
Server: thin 1.0.0 codename That's What She Said