Merge "warden: Use em-posix-spawn"

warden/Rakefile

@@ -11,6 +11,7 @@ namespace :warden do
   desc "Run Warden server"
   task :start do
     require "warden/server"
+    Warden::Server.setup
     Warden::Server.run!
   end
 end

warden/lib/warden/container/base.rb

@@ -3,6 +3,7 @@
 require "warden/container/script_handler"
 
 require "eventmachine"
+require "em/posix/spawn"
 require "set"
 
 module Warden
@@ -11,6 +12,8 @@ module Container
 
     class Base
 
+      include ::EM::POSIX::Spawn
+      include EventEmitter
       include Logger
 
       class << self
@@ -72,20 +75,30 @@ def initialize
         @jobs = {}
         @created = false
         @destroyed = false
-      end
 
-      def handle
-        @network.to_hex
-      end
+        on(:after_create) {
+          # Clients should be able to look this container up
+          self.class.registry[handle] = self
+        }
+
+        on(:before_destroy) {
+          # Clients should no longer be able to look this container up
+          self.class.registry.delete(handle)
+        }
 
-      def register
-        self.class.registry[handle] = self
-        nil
+        on(:after_destroy) {
+          # Release network address only if the container has successfully been
+          # destroyed. If not, the network address will "leak" and cannot be
+          # reused until this process is restarted. We should probably add
+          # extra logic to destroy a container in a failure scenario.
+          ::EM.add_timer(5) {
+            Server.network_pool.release(network)
+          }
+        }
       end
 
-      def unregister
-        self.class.registry.delete(handle)
-        nil
+      def handle
+        @network.to_hex
       end
 
       def gateway_ip
@@ -133,10 +146,9 @@ def create
 
         @created = true
 
+        emit(:before_create)
         do_create
-
-        # Any client should now be able to look this container up
-        register
+        emit(:after_create)
 
         handle
       end
@@ -156,18 +168,9 @@ def destroy
 
         @destroyed = true
 
-        # Clients should no longer be able to look this container up
-        unregister
-
+        emit(:before_destroy)
         do_destroy
-
-        # Release network address only if the container has successfully been
-        # destroyed. If not, the network address will "leak" and cannot be
-        # reused until this process is restarted. We should probably add extra
-        # logic to destroy a container in a failure scenario.
-        ::EM.add_timer(5) {
-          Server.network_pool.release(network)
-        }
+        emit(:after_destroy)
 
         "ok"
       end
@@ -215,10 +218,27 @@ def run(script)
 
       protected
 
-      def sh(command)
-        handler = ::EM.popen(command, ScriptHandler)
-        yield handler if block_given?
-        handler.yield # Yields fiber
+      def sh(*args)
+        env, argv, options =  extract_process_spawn_arguments(*args)
+        options = { :timeout => 5.0, :max => 1024 * 1024 }.merge(options)
+        p = Child.new(env, *(argv + [options]))
+
+        f = Fiber.current
+        p.callback { f.resume(:ok) }
+        p.errback { |err| f.resume(:err, err) }
+
+        status, err = Fiber.yield
+        if status == :err
+          message = case err
+                    when MaximumOutputExceeded
+                      "command exceeded maximum output"
+                    when TimeoutExceeded
+                      "command exceeded maximum runtime"
+                    else
+                      "unknown error"
+                    end
+          raise WardenError.new(message)
+        end
 
       rescue WardenError
         error "error running: #{command.inspect}"

warden/lib/warden/container/insecure.rb

@@ -39,20 +39,11 @@ def do_destroy
       end
 
       def create_job(script)
-        # Store script in temporary file. This is done because run.sh moves the
-        # subshell that actually runs the script to the background, and with
-        # that closes its stdin. In addition, we cannot capture stdin before
-        # executing the subshell because we cannot shutdown the write side of a
-        # socket from EM.
-        stdin = Tempfile.new("stdin", container_path)
-        stdin.write(script)
-        stdin.close
-
-        # Create new job and run script
         job = Job.new(self)
-        command = "env job_path=#{container_root_path}/#{job.path} #{container_path}/run.sh #{stdin.path}"
-        handler = ::EM.popen(command, RemoteScriptHandler)
-        handler.callback { job.finish }
+        env = { "job_path" => File.join(container_root_path, job.path) }
+        child = Child.new(env, File.join(container_path, "run.sh"), :input => script)
+        child.callback { job.finish }
+        child.errback { job.finish }
 
         job
       end

warden/lib/warden/server.rb

@@ -216,25 +216,25 @@ def process_create(request)
       end
 
       def process_destroy(request)
-        request.require_arguments 2
+        request.require_arguments { |n| n == 2 }
         container = find_container(request[1])
         container.destroy
       end
 
       def process_spawn(request)
-        request.require_arguments 3
+        request.require_arguments { |n| n == 3 }
         container = find_container(request[1])
         container.spawn(request[2])
       end
 
       def process_link(request)
-        request.require_arguments 3
+        request.require_arguments { |n| n == 3 }
         container = find_container(request[1])
         container.link(request[2])
       end
 
       def process_run(request)
-        request.require_arguments 3
+        request.require_arguments { |n| n == 3 }
         container = find_container(request[1])
         container.run(request[2])
       end
@@ -252,8 +252,8 @@ def find_container(handle)
 
       class Request < Array
 
-        def require_arguments(num)
-          if size != num
+        def require_arguments
+          unless yield(size)
             raise WardenError.new("invalid number of arguments")
           end
         end

warden/root/insecure/.instance-skeleton/run.sh

@@ -16,7 +16,7 @@ mkdir -p ${tmp}
 # Run script with PWD=root. Bash closes stdin for processes that is moves to
 # the background so we need to pass the script via a temporary file.
 cd root
-cat ${1:-/dev/null} > ${tmp}/stdin
+cat - > ${tmp}/stdin
 env -i bash < ${tmp}/stdin 1> ${tmp}/stdout 2> ${tmp}/stderr &
 cd ..
 

warden/warden.gemspec

@@ -20,4 +20,5 @@ Gem::Specification.new do |s|
 
   s.add_runtime_dependency "eventmachine"
   s.add_runtime_dependency "hiredis", "~> 0.4.0"
+  s.add_runtime_dependency "em-posix-spawn"
 end