Authd library added to provide an auto-check middleware.

src/authd.cr

@@ -0,0 +1,37 @@
+
+require "kemal"
+require "jwt"
+
+class HTTP::Server::Context
+	property authd_user : Hash(String, JSON::Any)?
+end
+
+class AuthD::Middleware < Kemal::Handler
+	property key : String = ""
+
+	@configured = false
+	@configurator : Proc(Middleware, Nil)
+
+	def initialize(&block : Proc(Middleware, Nil))
+		@configurator = block
+	end
+
+	def call(context)
+		unless @configured
+			@configured = true
+			@configurator.call self
+		end
+
+		context.request.headers["X-Token"]?.try do |x_token|
+			payload, header = JWT.decode x_token, @key, "HS256"
+
+			if payload
+				context.authd_user = payload
+			end
+		end
+
+		call_next context
+	end
+end
+
+