Exception: StandardError

Inherits:
Exception
  • Object
show all
Defined in:
lib/maveric/extensions.rb

Overview

Extensions to StandardError to enable their usage in Maveric as responses. The default response is 500 and content-type of text/plain.

Constant Summary collapse

DEFAULT_STATUS = 
500
DEFAULT_HEADERS = 
{'Content-Type'=>'text/plain'}

Instance Method Summary collapse

Constructor Details

#initialize(data = nil) ⇒ StandardError

After a bit of experimenting with Exception and raise I determined a fun and simple way to generate fast HTTP response error thingies. As long as you’re within a call to Maveric#dispatch (with no further rescue clauses) the StandardError will propogate up and be returned. As a StandardError has similar accessors as a Controller, they should be compatible with any outputting implimentation for Maveric.

raise StandardErrpr; # 500 error
raise StandardError, 'Crap!'; # 500 error with message set to 'Crap!'
raise StandardError, [status, headers, body, *other_data] # Magic!

In the final example line an Array is passed to raise as a second argument rather than a String. This is taken as the HTTP status code. The next element is tested to be a Hash, if so then it’s values are merged into the HTTP headers. The next item is tested to be a String, if so it is appended to the response body. All remaining elements are appended to the response body in inspect format.

A simple way of only including data that might be interpreted to being the status, headers, or body is to place a nil previous to the data you want appended to the response body.



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# File 'lib/maveric/extensions.rb', line 98

def initialize data=nil
  # consider autosetting @status, like 503 for NoMethodError
  if data.is_a? Array and data[0].is_a? Integer
    @body = ''
    @status = data.shift if Integer === data.first
    @headers = DEF_HEADERS.merge data.shift if Hash === data.first
    @body << data.shift if String === data.first
    msg = @body.dup
    @body << "\n\n#{data.compact.map{|e|e.inspect}*"\n"}" unless data.empty?
    data = msg
  end
  super data
end

Instance Method Details

#body ⇒ Object

Unless @body is defined, a self inspect and backtrace is output.



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# File 'lib/maveric/extensions.rb', line 62

def body
  defined?(@body)? @body : [inspect, *backtrace]*"\n"
end

#headers ⇒ Object

Returns @headers or DEFAULT_HEADERS if unset.



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# File 'lib/maveric/extensions.rb', line 57

def headers
  defined?(@headers)? @headers : DEFAULT_HEADERS
end

#status ⇒ Object

Returns @status or DEFAULT_STATUS if unset.



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# File 'lib/maveric/extensions.rb', line 52

def status
  defined?(@status)? @status : DEFAULT_STATUS
end

#to_http(raw = true) ⇒ Object

See Maveric::Controller#to_http



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# File 'lib/maveric/extensions.rb', line 67

def to_http(raw=true)
  response = if not raw then 'Status:'
    elsif defined? @env and @env.key? 'HTTP_VERSION' then @env['HTTP_VERSION']
    else 'HTTP/1.1'end
  response += " #{self.status}" + ::Maveric::EOL # Status message? :/
  response << self.headers.map{|k,v| "#{k}: #{v}" }*::Maveric::EOL
  response << ::Maveric::EOL*2 + self.body
end