Add "knife xargs" command to run a program against nodes, roles, cookbooks, etc.

1 files changed, 114 insertions, 0 deletions

diff --git a/lib/chef/knife/xargs.rb b/lib/chef/knife/xargs.rb
new file mode 100644
index 0000000000..1d8bcee5e4
--- /dev/null
+++ b/lib/chef/knife/xargs.rb
@@ -0,0 +1,114 @@
+require 'chef/chef_fs/knife'
+require 'chef/chef_fs/file_system'
+require 'chef/chef_fs/file_system/not_found_error'
+
+class Chef
+  class Knife
+    class Xargs < Chef::ChefFS::Knife
+      banner "knife xargs [PATTERN1 ... PATTERNn]"
+
+      common_options
+
+      # TODO modify to remote-only / local-only pattern (more like delete)
+      option :local,
+        :long => '--local',
+        :boolean => true,
+        :description => "Xargs local files instead of remote"
+
+      option :patterns,
+        :long => '--pattern [PATTERN]',
+        :short => '-p [PATTERN]',
+        :description => "Pattern on command line (if these are not specified, a list of patterns is expected on standard input)",
+        :arg_arity => [1,-1]
+
+      option :diff,
+        :long => '--[no-]diff',
+        :default => true,
+        :boolean => true,
+        :description => "Whether to show a diff when files change (default: true)"
+
+      option :dry_run,
+        :long => '--dry-run',
+        :boolean => true,
+        :description => "Prevents changes from actually being uploaded to the server."
+
+      option :force,
+        :long => '--[no-]force',
+        :boolean => true,
+        :default => false,
+        :description => "Force upload of files even if they are not changed (quicker and harmless, but doesn't print out what it changed)"
+
+      def run
+        error = false
+        command = name_args.join(' ')
+        # Get the matches (recursively)
+        pattern_args_from(get_patterns).each do |pattern|
+          Chef::ChefFS::FileSystem.list(config[:local] ? local_fs : chef_fs, pattern) do |result|
+            if result.dir?
+              # TODO option to include directories
+              ui.warn "#{format_path(result)}: is a directory.  Will not run #{command} on it."
+            else
+              begin
+                value = result.read
+                tmpfile = Tempfile.open(result.name)
+                begin
+                  tmpfile.write(value)
+                  tmpfile.close
+                  puts "#{command} #{format_path(result)}"
+                  # TODO replace tmpfile name in output with real path
+                  system("#{command} #{tmpfile.path}")
+
+                  # Check if it's different
+                  tmpfile.open
+                  new_value = tmpfile.read
+                  tmpfile.close
+                  if config[:force] || new_value != value
+                    if config[:dry_run]
+                      puts "Would update #{format_path(result)}"
+                    else
+                      result.write(new_value)
+                      puts "Updated #{format_path(result)}"
+                    end
+
+                    if config[:diff]
+                      old_file = Tempfile.open(result.name)
+                      begin
+                        old_file.write(value)
+                        old_file.close
+
+                        system("diff -u #{old_file.path} #{tmpfile.path}")
+                      ensure
+                        old_file.close!
+                      end
+                    end
+                  end
+                ensure
+                  tmpfile.close! # Unlink the file now that we're done with it
+                end
+
+              rescue Chef::ChefFS::FileSystem::OperationNotAllowedError => e
+                ui.error "#{format_path(e.entry)}: #{e.reason}."
+                error = true
+              rescue Chef::ChefFS::FileSystem::NotFoundError => e
+                ui.error "#{format_path(e.entry)}: No such file or directory"
+                error = true
+              end
+            end
+          end
+        end
+        if error
+          exit 1
+        end
+      end
+
+      def get_patterns
+        if config[:patterns]
+          [ config[:patterns] ].flatten
+        else
+          stdin.lines.map { |line| line.chomp }
+        end
+      end
+    end
+  end
+end
+