Add the idea of a debug flag to make the vagrant commands output expl…

…icit to the end user. Also does the changes necessaries to make the vagrant command runner fetch the stdout and stdin on demand and not waiting till the end of it to report.

Fixes elastic#5566

qa/Rakefile

@@ -35,8 +35,9 @@ namespace :qa do
 
       puts user_feedback_string_for("bootstraping", args[:platform], machines, {"experimental" => experimental})
 
-      LogStash::VagrantHelpers.destroy(machines)
-      LogStash::VagrantHelpers.bootstrap(machines)
+      options = {:debug => ENV['LS_QA_DEBUG']}
+      LogStash::VagrantHelpers.destroy(machines, options)
+      LogStash::VagrantHelpers.bootstrap(machines, options)
     end
 
     desc "Halt all VM's involved in the acceptance test round"
@@ -46,8 +47,9 @@ namespace :qa do
       machines = config.select_names_for(args[:platform], {"experimental" => experimental})
 
       puts user_feedback_string_for("halting", args[:platform], machines, {"experimental" => experimental})
+      options = {:debug => ENV['LS_QA_DEBUG']}
 
-      LogStash::VagrantHelpers.halt(machines)
+      LogStash::VagrantHelpers.halt(machines, options)
     end
   end
 

qa/vagrant/command.rb

@@ -21,25 +21,51 @@ def success?
       end
     end
 
-    def self.run(cmd)
+    def self.run(cmd, debug=false)
       # This block is require to be able to launch a ruby subprocess
       # that use bundler.
       Bundler.with_clean_env do
-        Open3.popen3(cmd) do |stdin, stdout, stderr, wait_thr|
-          CommandResponse.new(stdin, stdout.read.chomp, stderr.read.chomp, wait_thr.value.exitstatus)
+        stdin, stdout, stderr, wait_thr = Open3.popen3(cmd)
+        stdout_acc, stderr_acc = "", ""
+        stdout_reporter = reporter(stdout, wait_thr) do |c|
+          stdout_acc << c
+          print c if debug
         end
+        reporter(stderr, wait_thr) do |c|
+          stderr_acc << c;
+          print c if debug
+        end
+        stdout_reporter.join
+        CommandResponse.new(stdin, stdout_acc, stderr_acc, wait_thr.value.exitstatus)
       end
     end
 
     # This method will raise an exception if the `CMD`
     # was not run successfully and will display the content of STDERR
-    def self.run!(cmd)
-      response = run(cmd)
+    def self.run!(cmd, debug=false)
+      response = run(cmd, debug)
 
       unless response.success?
         raise CommandError, "CMD: #{cmd} STDERR: #{response.stderr}"
       end
       response
     end
+
+    private
+
+    def self.reporter(io, wait_thr, &block)
+      Thread.new(io, wait_thr) do |_io, _wait_thr|
+        while (_wait_thr.status == "run")
+          begin
+            c = _io.read(1)
+            block.call(c) if c
+          rescue IO::WaitReadable
+            IO.select([_io])
+            retry
+          end
+        end
+      end
+    end
+
   end
 end

qa/vagrant/helpers.rb

@@ -6,16 +6,19 @@
 module LogStash
   class VagrantHelpers
 
-    def self.halt(machines="")
-      CommandExecutor.run!("vagrant halt #{machines.join(' ')}")
+    def self.halt(machines="", options={})
+      debug = options.fetch(:debug, false)
+      CommandExecutor.run!("vagrant halt #{machines.join(' ')}", debug)
     end
 
-    def self.destroy(machines="")
-      CommandExecutor.run!("vagrant destroy --force #{machines.join(' ')}") 
+    def self.destroy(machines="", options={})
+      debug = options.fetch(:debug, false)
+      CommandExecutor.run!("vagrant destroy --force #{machines.join(' ')}", debug) 
     end
 
-    def self.bootstrap(machines="")
-      CommandExecutor.run!("vagrant up #{machines.join(' ')}")
+    def self.bootstrap(machines="", options={})
+      debug = options.fetch(:debug, false)
+      CommandExecutor.run!("vagrant up #{machines.join(' ')}", debug)
     end
 
     def self.save_snapshot(machine="")