Run commands from file on Windows when using exec transport

Windows limits the length of commands that can be run via powershell which
breaks the exec transport. To work around the issue, when running on a Windows
host, the command to a file and then execute the file, and then remove the file.

This resolves test-kitchen#1630.

Signed-off-by: Lance Albertson <[email protected]>

lib/kitchen/transport/exec.rb

@@ -28,7 +28,7 @@ class Exec < Kitchen::Transport::Base
       plugin_version Kitchen::VERSION
 
       def connection(state, &block)
-        options = config.to_hash.merge(state)
+        options = connection_options(config.to_hash.merge(state))
         Kitchen::Transport::Exec::Connection.new(options, &block)
       end
 
@@ -40,19 +40,105 @@ class Connection < Kitchen::Transport::Base::Connection
         def execute(command)
           return if command.nil?
 
-          run_command(command)
+          if host_os_windows?
+            run_command(run_from_file_command(command))
+            close
+          else
+            run_command(command)
+          end
+        end
+
+        def close
+          if host_os_windows?
+            FileUtils.remove(exec_script_file)
+          end
         end
 
         # "Upload" the files by copying them locally.
         #
         # @see Base#upload
         def upload(locals, remote)
-          FileUtils.mkdir_p(remote)
+          # evaluate $env:temp on Windows
+          real_remote = remote.to_s == "\$env:TEMP\\kitchen" ? kitchen_temp : remote
+          FileUtils.mkdir_p(real_remote)
           Array(locals).each do |local|
-            FileUtils.cp_r(local, remote)
+            FileUtils.cp_r(local, real_remote)
+          end
+        end
+
+        # (see Base#init_options)
+        def init_options(options)
+          super
+          @instance_name = @options.delete(:instance_name)
+          @kitchen_root = @options.delete(:kitchen_root)
+        end
+
+        private
+
+        # @return [String] display name for the associated instance
+        # @api private
+        attr_reader :instance_name
+
+        # @return [String] local path to the root of the project
+        # @api private
+        attr_reader :kitchen_root
+
+        # Takes a long command and saves it to a file and uploads it to
+        # the test instance. Windows has cli character limits.
+        #
+        # @param command [String] a long command to be saved and uploaded
+        # @return [String] a command that executes the uploaded script
+        # @api private
+        def run_from_file_command(command)
+          if logger.debug?
+            debug("Creating exec script for #{instance_name} (#{exec_script_file})")
+            debug("Executing #{exec_script_file}")
+          end
+          File.open(exec_script_file, "wb") { |file| file.write(command) }
+          %{powershell -file "#{exec_script_file}"}
+        end
+
+        # @return [String] evaluated $env:temp variable
+        # @api private
+        def kitchen_temp
+          "#{ENV["temp"]}/kitchen"
+        end
+
+        # @return [String] name of script using instance name
+        # @api private
+        def exec_script_name
+          "#{instance_name}-exec-script.ps1"
+        end
+
+        # @return [String] file path for exec script to be run
+        # @api private
+        def exec_script_file
+          File.join(kitchen_root, ".kitchen", exec_script_name)
+        end
+
+        def host_os_windows?
+          case RbConfig::CONFIG["host_os"]
+          when /mswin|msys|mingw|cygwin|bccwin|wince|emc/
+            true
+          else
+            false
           end
         end
+      end
+
+      private
 
+      # Builds the hash of options needed by the Connection object on construction.
+      #
+      # @param data [Hash] merged configuration and mutable state data
+      # @return [Hash] hash of connection options
+      # @api private
+      def connection_options(data)
+        opts = {
+          instance_name: instance.name,
+          kitchen_root: Dir.pwd,
+        }
+        opts
       end
     end
   end

spec/kitchen/transport/exec_spec.rb

@@ -16,7 +16,12 @@
 
 require "kitchen/transport/exec"
 
-describe Kitchen::Transport::Ssh do
+describe Kitchen::Transport::Exec do
+
+  before do
+    RbConfig::CONFIG.stubs(:[]).with("host_os").returns("blah")
+  end
+
   let(:logged_output) { StringIO.new }
   let(:logger)        { Logger.new(logged_output) }
   let(:config)        { {} }
@@ -39,15 +44,62 @@
   end
 
   describe "#connection" do
-    it "returns a Kitchen::Transport::Exec::Connection object" do
-      transport.connection(state).must_be_kind_of Kitchen::Transport::Exec::Connection
+    let(:klass) { Kitchen::Transport::Exec::Connection }
+
+    def self.common_connection_specs
+      before do
+        config[:kitchen_root] = "/i/am/root"
+      end
+
+      it "returns a Kitchen::Transport::Exec::Connection object" do
+        transport.connection(state).must_be_kind_of klass
+      end
+
+      it "sets :instance_name to the instance's name" do
+        klass.expects(:new).with do |hash|
+          hash[:instance_name] == "coolbeans"
+        end
+
+        make_connection
+      end
+
+      it "sets :kitchen_root to the transport's kitchen_root" do
+        klass.expects(:new).with do |hash|
+          hash[:kitchen_root] == "/i/am/root"
+        end
+
+        make_connection
+      end
+
+      describe "called without a block" do
+        def make_connection(s = state) # rubocop:disable Lint/NestedMethodDefinition
+          transport.connection(s)
+        end
+
+        common_connection_specs
+      end
+
+      describe "called with a block" do
+        def make_connection(s = state) # rubocop:disable Lint/NestedMethodDefinition
+          transport.connection(s) do |conn|
+            conn
+          end
+        end
+
+        common_connection_specs
+      end
     end
   end
 end
 
 describe Kitchen::Transport::Exec::Connection do
+  before do
+    RbConfig::CONFIG.stubs(:[]).with("host_os").returns("blah")
+  end
+
   let(:logged_output)   { StringIO.new }
   let(:logger)          { Logger.new(logged_output) }
+  let(:exec_script)     { File.join("/tmp/.kitchen/instance-exec-script.ps1") }
 
   let(:options) do
     { logger: logger }
@@ -67,6 +119,43 @@
       connection.expects(:run_command).never
       connection.execute(nil)
     end
+    describe "for windows-based workstations" do
+      before do
+        RbConfig::CONFIG.stubs(:[]).with("host_os").returns("mingw32")
+        options[:kitchen_root] = "/tmp"
+        options[:instance_name] = "instance"
+      end
+
+      it "runs the command" do
+        stub_file(exec_script, "")
+        connection.expects(:run_command).with("powershell -file \"#{exec_script}\"")
+        connection.execute("do the thing")
+      end
+
+      it "ignores nil" do
+        connection.expects(:run_command).never
+        connection.execute(nil)
+      end
+    end
+  end
+
+  describe "#close" do
+    it "Does not remove exec script file" do
+      FileUtils.expects(:remove).with(exec_script).never
+      connection.close
+    end
+
+    describe "for windows-based workstations" do
+      before do
+        RbConfig::CONFIG.stubs(:[]).with("host_os").returns("mingw32")
+        options[:kitchen_root] = "/tmp"
+        options[:instance_name] = "instance"
+      end
+      it "Removes exec script file" do
+        FileUtils.expects(:remove).with(exec_script)
+        connection.close
+      end
+    end
   end
 
   describe "#upload" do
@@ -75,5 +164,18 @@
       FileUtils.expects(:cp_r).with("/tmp/sandbox/cookbooks", "/tmp/kitchen")
       connection.upload(%w{/tmp/sandbox/cookbooks}, "/tmp/kitchen")
     end
+    it "copies files when $env:temp is set" do
+      ENV["temp"] = "/tmp"
+      FileUtils.expects(:mkdir_p).with("/tmp/kitchen")
+      FileUtils.expects(:cp_r).with("/tmp/sandbox/cookbooks", "/tmp/kitchen")
+      connection.upload(%w{/tmp/sandbox/cookbooks}, "\$env:TEMP\\kitchen")
+    end
+  end
+
+  private
+
+  def stub_file(path, content)
+    FileUtils.mkdir_p(File.dirname(path))
+    File.open(path, "wb") { |f| f.write(content) }
   end
 end