Class: HTTPRange::Middleware::AcceptRanges

Inherits:
Object
  • Object
show all
Defined in:
lib/http_range/middleware/accept_ranges.rb

Overview

Rack Middleware for parsing ‘Range` headers. See [SPEC] for more details.

[1]: https://github.com/h3h/http_range/blob/master/SPEC.md

Request Header Format:

Range: <attr> <first>..<last>[; order=<asc|desc>][; max=<int>]

Examples:

Range: id 29f99177-36e9-466c-baef-f855e1ab731e..6c714be1-d901-4c40-adb3-22c9a8cda950; max=100
Range: created_at 2014-09-18T16:30:38Z..2014-09-18T17:30:33Z; order=desc

Output:

‘env` keys exposed from the parsed content of the requested Range header:

- env['rack.range.attribute']: attribute name
- env['rack.range.first']:           first value in the range
- env['rack.range.last']:            last value in the range
- env['rack.range.first_inclusive']: whether the first value is inclusive
- env['rack.range.last_inclusive']:  whether the last value is inclusive
- env['rack.range.order']:           order param
- env['rack.range.max']:             max param

Usage:

use HTTPRange::Middleware::AcceptRanges

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ AcceptRanges

Returns a new instance of AcceptRanges.



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# File 'lib/http_range/middleware/accept_ranges.rb', line 38

def initialize(app)
  @app = app
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/http_range/middleware/accept_ranges.rb', line 42

def call(env)
  range_header = env['HTTP_RANGE']
  if range_header && range_header.length > 0
    http_range = HTTPRange.parse(range_header)

    set_env_fields(
      env:             env,
      attribute:       http_range.attribute,
      first:           http_range.first,
      last:            http_range.last,
      first_inclusive: http_range.first_inclusive,
      last_inclusive:  http_range.last_inclusive,
      order:           http_range.order,
      max:             http_range.max,
    )
  end

  @app.call(env)
rescue HTTPRange::MalformedRangeHeaderError => ex
  [400, {'Content-Type' => 'application/json'}, [{errors: [ex.message]}.to_json]]
end