I am using AirBnb Nerve service. It's service code looks like this:
require 'logger'
require 'json'
require 'timeout'
require 'nerve/version'
require 'nerve/utils'
require 'nerve/log'
require 'nerve/ring_buffer'
require 'nerve/reporter'
require 'nerve/service_watcher'
module Nerve
class Nerve
include Logging
def initialize(opts={})
log.info 'nerve: starting up!'
# set global variable for exit signal
$EXIT = false
...some code...
# Any exceptions in the watcher threads should wake the main thread so
# that we can fail fast.
Thread.abort_on_exception = true
log.debug 'nerve: completed init'
end
def run
log.info 'nerve: starting run'
#services.each do |name, config|
launch_watcher(name, config)
end
begin
sleep
rescue StandardError => e
log.error "nerve: encountered unexpected exception #{e.inspect} in main thread"
raise e
ensure
$EXIT = true
log.warn 'nerve: reaping all watchers'
#watchers.each do |name, watcher_thread|
reap_watcher(name)
end
end
log.info 'nerve: exiting'
ensure
$EXIT = true
end
def launch_watcher(name, config)
... some code ...
end
def reap_watcher(name)
... some code ...
end
end
end
I do not see any stop method. What is the right way of stopping such a service? I am using JRuby and intend to write a JSVC adapter for this service.
There is no way to do this via the current API, short of sending it a signal.
If sending a signal isn't going to work and you want to handle stop explicitly, it looks like you will need to change the following things:
Add a #stop method to Nerve that sets $EXIT = true.
Modify #run so that rather than sleeping forever (sleep) it wakes up and checks $EXIT.
Related
I want to run the startdrb method concurrently with the printstuff method on a Windows system. I messed around with Thread.new but the service starts and terminates after the thread completes.
How would this be written?
require 'drb'
require 'drb/ssl'
class TestDRB
def dostuff
...
end
def startdrb
begin
config = {SSLCertName: [["CN","DRuby"]]}
DRb.start_service("drbssl://127.0.0.1:9911", BHRBeacon.new, config)
rescue Exception => e
puts e.full_message
end
def printstuff
begin
puts "this will run while Drb service is also running"
end
TestDRB.new.startdrb
TestDRB.new.printstuff
im building a small game in ruby to practice programming, so far everything has went well but im trying to implement multiplayer support, i can connect to the server and i can send information but when I try to read form the server it just freezes and my screen goes completely black. and i cant find the cause, ive read the documentation for the gem im using for TCP and i dont know, maybe i missed something, but if any of you have some insight I would really appreciate it
heres the repo if this code isnt enough
https://github.com/jaypitti/ruby-2d-gosu-game
heres the client side code
class Client
include Celluloid::IO
def initialize(server, port)
begin
#socket = TCPSocket.new(server, port)
rescue
$error_message = "Cannot find game server."
end
end
def send_message(message)
#socket.write(message) if #socket
end
def read_message
#socket.readpartial(4096) if #socket
end
end
heres the gameserver
require 'celluloid/autostart'
require 'celluloid/io'
class Server
include Celluloid::IO
finalizer :shutdown
def initialize(host, port)
puts "Starting Server on #{host}:#{port}."
#server = TCPServer.new(host, port)
#objects = Hash.new
#players = Hash.new
async.run
end
def shutdown
#server.close if #server
end
def run
loop { async.handle_connection #server.accept }
end
def handle_connection(socket)
_, port, host = socket.peeraddr
user = "#{host}:#{port}"
puts "#{user} has joined the arena."
loop do
data = socket.readpartial(4096)
data_array = data.split("\n")
if data_array and !data_array.empty?
begin
data_array.each do |row|
message = row.split("|")
if message.size == 10
case message[0]
when 'obj'
#players[user] = message[1..9] unless #players[user]
#objects[message[1]] = message[1..9]
when 'del'
#objects.delete message[1]
end
end
response = String.new
#objects.each_value do |obj|
(response << obj.join("|") << "\n") if obj
end
socket.write response
end
rescue Exception => exception
puts exception.backtrace
end
end # end data
end # end loop
rescue EOFError => err
player = #players[user]
puts "#{player[3]} has left"
#objects.delete player[0]
#players.delete user
socket.close
end
end
server, port = ARGV[0] || "0.0.0.0", ARGV[1] || 1234
supervisor = Server.supervise(server, port.to_i)
trap("INT") do
supervisor.terminate
exit
end
sleep
it just freezes and my screen goes completely black. and i cant find the cause
A good trick you can look at is attaching to your process with either rbspy or rbtrace to see that is going on when it is stuck.
You can also try first reducing dependencies here a bit and doing this with a simple threadpool prior to going full async with celluloid or event machine.
First of all you should not be rescuing Exception all over the place. Wrapping long begin rescue blocks around nested iterators is begging for trouble.
It sounds like a threading issues, memory and/or CPU but that's just a guess. Try to monitor your resources or use some performance checking gems. But for the love of Satoshi Nakamoto, please write some test coverage and see your methods fail miserably, then fix them!
Some of these may help:
group :development do
gem 'bullet', require: false
gem 'flamegraph', require: false
gem 'memory_profiler', require: false
gem 'rack-mini-profiler', require: false
gem 'seed_dump'
gem 'stackprof', require: false
gem 'traceroute', require: false
end
I have a jruby class which contains a heartbeat that does something every certain number of seconds: (simplified code below)
class Client
def initialise
#interval = 30
#heartbeat = Thread.new do
begin
loop do
puts "heartbeat"
sleep #interval
end
rescue Exception => e
Thread.main.raise e
end
end
end
end
And I have a range of rspec tests that instantiate this class.
At the end of each test, I would expect the object to be destroyed, but the threads seem to remain.
At the moment I've fixed this with:
client.rb:
def kill
#heartbeat.kill
end
rspec:
after(:all) do
client.kill
end
Which seems to do the job - but this doesn't feel like the best way to do it.
What is the best way to approach this?
Using version jruby-9.1.10.0 & rspec 3.7.0
Edit:
As per http://ruby-doc.org/core-2.4.0/Thread.html I would expect the thread to normally terminate when the main thread does
In my tests I instantiate the client with
describe Client do
context 'bla' do
let(:client) do
described_class.new
end
it 'blas' do
end
end
end
You should replace after(:all) with after(:each).
Should be the correct syntax for what you want to do because after(:all) evaluates after all test cases have been run.
I have a problem with the testing the Sensu Plugin.
Everytime when I start rspec to test plugin it test it, but anyway at the end of test, the original plugin is started automatically. So I have in my console:
Finished in 0 seconds (files took 0.1513 seconds to load)
1 example, 0 failures
CheckDisk OK: # This comes from the plugin
Short explanation how my system works:
Plugin call system 'wmic' command, processes it, checks the conditions about the disk parameters and returns the exit statuses (ok, critical, etc)
Rspec mocks the response from system and sets into the input of plugin. At the end rspec checks the plugin exit status when the mocked input is given.
My plugin looks like that:
require 'rubygems' if RUBY_VERSION < '1.9.0'
require 'sensu-plugin/check/cli'
class CheckDisk < Sensu::Plugin::Check::CLI
def initialize
super
#crit_fs = []
end
def get_wmic
`wmic volume where DriveType=3 list brief`
end
def read_wmic
get_wmic
# do something, fill the class variables with system response
end
def run
severity = "ok"
msg = ""
read_wmic
unless #crit_fs.empty?
severity = "critical"
end
case severity
when /ok/
ok msg
when /warning/
warning msg
when /critical/
critical msg
end
end
end
Here is my test in Rspec:
require_relative '../check-disk.rb'
require 'rspec'
def loadFile
#Load template of system output when ask 'wmic volume(...)
end
def fillParametersInTemplate (template, parameters)
#set mocked disk parameters in template
end
def initializeMocks (options)
mockedSysOutput = fillParametersInTemplate #loadedTemplate, options
po = String.new(mockedSysOutput)
allow(checker).to receive(:get_wmic).and_return(po) #mock system call here
end
describe CheckDisk do
let(:checker) { described_class.new }
before(:each) do
#loadedTemplate = loadFile
def checker.critical(*_args)
exit 2
end
end
context "When % of free disk space = 10 >" do
options = {:diskName => 'C:\\', :diskSize => 1000, :diskFreeSpace => 100}
it 'Returns ok exit status ' do
begin
initializeMocks options
checker.run
rescue SystemExit => e
exit_code = e.status
end
expect(exit_code).to eq 0
end
end
end
I know that I can just put "exit 0" after the last example, but this is not a solution because when I will try to start many spec files it will exit after the first one. How to start only test, without running the plugin? Maybe someone can help me and show how to handle with such problem?
Thank you.
You can stub the original plugin call and optionally return a dummy object:
allow(SomeObject).to receive(:method) # .and_return(double)
you can put it in the before block to make sure that all assertions will share the code.
Another thing is that you are using rescue blocks to catch the situation when your code aborts with an error. You should use raise_error matcher instead:
expect { run }.to raise_error(SystemExit)
I'm writing Selenium tests, using Watir-Webdriver and RSpec, which can be a bit spotty when they're first being developed. I've run into a situation where I want to create something on the UI in before :all, however it can throw exceptions (based on timing or poor loading). When that happens I want to take a screenshot.
Here's what I have:
RSpec.configure do |config|
config.before(:all) do |group| #ExampleGroup
#browser = Watir::Browser.new $BROWSER
begin
yield #Fails on yield, there is no block
rescue StandardError => e
Utilities.create_screenshot(#browser)
raise(e)
end
end
end
I run it and get an error:
LocalJumpError: no block given (yield)
The reason I assumed yielding would work is RSpec's definition of before:
def before(*args, &block)
hooks.register :append, :before, *args, &block
end
How can I wrap the code I've put in my before :all in a begin/rescue block without having to do it on every suite?
Thanks in advanced.
The code you've written in the before hook is the &block you're referring to in RSpec::Hooks#before. The hook yields to your code, then runs your tests after the yield is complete.
As for how to make this work, I think this should do:
RSpec.configure do |config|
# ensures tests are run in order
config.order = 'defined'
# initiates Watir::Browser before all tests
config.before(:all) do
#browser = Watir::Browser.new $BROWSER
end
# executes Utilities.create_screenshot if an exception is raised by RSpec
# and the test is tagged with the :first metadata
config.around(:each) do |example|
example.run
Utilities.create_screenshot(#browser) if example.exception && example.metadata[:first]
end
end
This configuration requires the first test be tagged with metadata:
describe Thing, :first do
it "does something" do
# ...
end
end
This way, you'll only take a screenshot at the beginning of your run for a failing test, and not after every failing test. If you'd rather not mess with metadata (or prefer your tests are run in random order), you could do something like this:
RSpec.configure do |config|
# initiates Watir::Browser before all tests
config.before(:all) do
#test_count = 0
#browser = Watir::Browser.new $BROWSER
end
# executes Utilities.create_screenshot if an exception is raised by RSpec
# and the test is the first to run
config.around(:each) do |example|
#test_count += 1
example.run
Utilities.create_screenshot(#browser) if example.exception && #test_count == 1
end
end
This works for me. Instead of begin/rescue in the before :all hook,
config.after :each do
example_exceptions = []
RSpec.world.example_groups.each do |example_group|
example_group.examples.each do |example|
example_exceptions << !example.exception.nil?
end
end
has_exceptions = example_exceptions.any? {|exception| exception}
#Handle if anything has exceptions
end