set timeouts for CanvasHttp requests

fixes CNVS-24680

Change-Id: I8317983ea8f735aa5eb2d99bb7b5750e2727d03b
Reviewed-on: https://gerrit.instructure.com/66714
Tested-by: Jenkins
Reviewed-by: Simon Williams <simon@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>

config/initializers/canvas_http.rb

@@ -0,0 +1,2 @@
+CanvasHttp.open_timeout = -> { Setting.get('http_open_timeout', 5).to_f }
+CanvasHttp.read_timeout = -> { Setting.get('http_read_timeout', 30).to_f }

gems/canvas_http/lib/canvas_http.rb

@@ -68,9 +68,23 @@ module CanvasHttp
   def self.connection_for_uri(uri)
     http = Net::HTTP.new(uri.host, uri.port)
     http.use_ssl = (uri.scheme == 'https')
+    http.ssl_timeout = http.open_timeout = open_timeout
+    http.read_timeout = read_timeout
     return http
   end
 
+  def self.open_timeout
+    @open_timeout.respond_to?(:call) ? @open_timeout.call : @open_timeout || 5
+  end
+
+  def self.read_timeout
+    @read_timeout.respond_to?(:call) ? @read_timeout.call : @read_timeout || 30
+  end
+
+  class << self
+    attr_writer :open_timeout, :read_timeout
+  end
+
   # returns a tempfile with a filename based on the uri (same extension, if
   # there was an extension)
   def self.tempfile_for_uri(uri)

gems/canvas_http/spec/canvas_http_spec.rb

@@ -50,6 +50,9 @@ describe "CanvasHttp" do
       expect(http).to receive(:use_ssl=).with(true)
       expect(http).to receive(:verify_mode=).with(OpenSSL::SSL::VERIFY_NONE)
       expect(http).to receive(:request).and_yield(double(body: 'Hello SSL'))
+      expect(http).to receive(:open_timeout=).with(5)
+      expect(http).to receive(:ssl_timeout=).with(5)
+      expect(http).to receive(:read_timeout=).with(30)
 
       CanvasHttp.get("https://www.example.com/a/b").body.should == "Hello SSL"
     end