class WEBrick::HTTPServlet::AbstractServlet
AbstractServlet
allows HTTP server modules to be reused across multiple servers and allows encapsulation of functionality.
By default a servlet will respond to GET, HEAD (through an alias to GET) and OPTIONS requests.
By default a new servlet is initialized for every request. A servlet instance can be reused by overriding ::get_instance
in the AbstractServlet
subclass.
A Simple Servlet¶ ↑
class Simple < WEBrick::HTTPServlet::AbstractServlet def do_GET request, response status, content_type, body = do_stuff_with request response.status = status response['Content-Type'] = content_type response.body = body end def do_stuff_with request return 200, 'text/plain', 'you got a page' end end
This servlet can be mounted on a server at a given path:
server.mount '/simple', Simple
Servlet Configuration¶ ↑
Servlets can be configured via initialize. The first argument is the HTTP server the servlet is being initialized for.
class Configurable < Simple def initialize server, color, size super server @color = color @size = size end def do_stuff_with request content = "<p " \ %q{style="color: #{@color}; font-size: #{@size}"} \ ">Hello, World!" return 200, "text/html", content end end
This servlet must be provided two arguments at mount time:
server.mount '/configurable', Configurable, 'red', '2em'
Public Class Methods
Factory for servlet instances that will handle a request from server
using options
from the mount point. By default a new servlet instance is created for every call.
# File webrick/httpservlet/abstract.rb, line 83 def self.get_instance(server, *options) self.new(server, *options) end
Initializes a new servlet for server
using options
which are stored as-is in +@options+. +@logger+ is also provided.
# File webrick/httpservlet/abstract.rb, line 91 def initialize(server, *options) @server = @config = server @logger = @server[:Logger] @options = options end
Public Instance Methods
Raises a NotFound exception
# File webrick/httpservlet/abstract.rb, line 115 def do_GET(req, res) raise HTTPStatus::NotFound, "not found." end
Dispatches to do_GET
# File webrick/httpservlet/abstract.rb, line 122 def do_HEAD(req, res) do_GET(req, res) end
Returns the allowed HTTP request methods
# File webrick/httpservlet/abstract.rb, line 129 def do_OPTIONS(req, res) m = self.methods.grep(/\Ado_([A-Z]+)\z/) {$1} m.sort! res["allow"] = m.join(",") end
Dispatches to a do_
method based on req
if such a method is available. (do_GET
for a GET request). Raises a MethodNotAllowed exception if the method is not implemented.
# File webrick/httpservlet/abstract.rb, line 102 def service(req, res) method_name = "do_" + req.request_method.gsub(/-/, "_") if respond_to?(method_name) __send__(method_name, req, res) else raise HTTPStatus::MethodNotAllowed, "unsupported method `#{req.request_method}'." end end
Private Instance Methods
Redirects to a path ending in /
# File webrick/httpservlet/abstract.rb, line 140 def redirect_to_directory_uri(req, res) if req.path[-1] != ?/ location = WEBrick::HTTPUtils.escape_path(req.path + "/") if req.query_string && req.query_string.bytesize > 0 location << "?" << req.query_string end res.set_redirect(HTTPStatus::MovedPermanently, location) end end