Merge pull request #38 from jistr/output_sorting

Output sorting

features/usage.feature

@@ -51,6 +51,7 @@ Feature: Usage
     
     Options:
       [--fields=FIELDS]                # Fields (attributes) to print in the listing
+      [--sort-by=SORT_BY]              # Sort output by value of field(s)
       [--conductor-url=CONDUCTOR_URL]  
       [--username=USERNAME]            
       [--password=PASSWORD]            
@@ -87,6 +88,7 @@ Feature: Usage
     
     Options:
       [--fields=FIELDS]                # Fields (attributes) to print in the listing
+      [--sort-by=SORT_BY]              # Sort output by value of field(s)
       [--conductor-url=CONDUCTOR_URL]  
       [--username=USERNAME]            
       [--password=PASSWORD]            

lib/aeolus_cli/common_cli.rb

@@ -48,14 +48,20 @@ def banner(task, namespace = nil, subcommand = false)
 
     def method_options_for_resource_list
       method_option_fields
-      # TODO: method_option_sort_by
+      method_option_sort_by
     end
 
     def method_option_fields
       method_option :fields,
         :type => :string,
         :desc => 'Fields (attributes) to print in the listing'
     end
+
+    def method_option_sort_by
+      method_option :sort_by,
+        :type => :string,
+        :desc => 'Sort output by value of field(s)'
+    end
   end
 
   def load_aeolus_config(options)
@@ -145,6 +151,25 @@ def resource_fields(fields_option)
     fields_option.split(',').map { |option| option.to_sym }
   end
 
+  def resource_sort_by(sort_by_option)
+    return nil unless sort_by_option
+    if sort_by_option == ''
+      raise Thor::MalformattedArgumentError.new("Option 'sort_by' cannot be empty.")
+    end
+    sort_by_option.split(',').map { |option| parse_one_sort_by_option(option) }
+  end
+
+  def parse_one_sort_by_option(option)
+    case option[-1]
+    when '+'
+      [option[0..-2].to_sym, :asc]
+    when '-'
+      [option[0..-2].to_sym, :desc]
+    else
+      [option.to_sym, :asc]
+    end
+  end
+
   def provider_type(type_s)
     # we need to hit the API to get the map of provider_type.name =>
     # provider_type.id, so make sure we only do this once.

lib/aeolus_cli/formatting/format.rb

@@ -1,4 +1,5 @@
 require 'aeolus_cli/formatting/errors'
+require 'aeolus_cli/formatting/presenter_sorter'
 
 module AeolusCli::Formatting
   # This class (or more precisely, classes that inherit from this one) can
@@ -30,6 +31,14 @@ def presenter_for(object, fields_override = nil)
       presenter_class.new(object, fields_override)
     end
 
+    # Gets an array of presenters for array of objects. The array sorted
+    # according to the sort_by parameter. See PresenterSorter for details how
+    # sorting works.
+    def presenters_for(objects, fields_override = nil, sort_by = nil)
+      presenters = objects.map { |object| presenter_for(object, fields_override) }
+      PresenterSorter.new(presenters, sort_by).sorted_presenters
+    end
+
     # Registers a presenter to use for objects of some type.
     def register(class_name, presenter)
       @presenters[class_name] = presenter

lib/aeolus_cli/formatting/human_format.rb

@@ -32,13 +32,14 @@ def detail(object, fields_override = nil)
     def list(objects, fields_override = nil, sort_by = nil)
       return if objects.empty?
 
-      table = []
+      presenters = presenters_for(objects, fields_override, sort_by)
 
+      table = []
       # table header
-      table << presenter_for(objects.first, fields_override).list_table_header
+      table << presenters.first.list_table_header
 
-      objects.each do |object|
-        table << presenter_for(object, fields_override).list_item
+      presenters.each do |presenter|
+        table << presenter.list_item
       end
 
       print_table(table)

lib/aeolus_cli/formatting/machine_format.rb

@@ -22,9 +22,11 @@ def detail(object, fields_override = nil)
     def list(objects, fields_override = nil, sort_by = nil)
       return if objects.empty?
 
+      presenters = presenters_for(objects, fields_override, sort_by)
+
       list = []
-      objects.each do |object|
-        list << presenter_for(object, fields_override).list_item
+      presenters.each do |presenter|
+        list << presenter.list_item
       end
 
       print_list(list, @separator)

lib/aeolus_cli/formatting/presenter_sorter.rb

@@ -0,0 +1,36 @@
+module AeolusCli::Formatting
+  # Sorts array of Presenter objects by their field values.
+  class PresenterSorter
+    # Parameter sort_by is expected like e.g. [[:status, :desc], [:name, :asc]],
+    # which means "sort by status descending, and if status is the same, sort
+    # by name ascending".
+    def initialize(presenters, sort_by)
+      @presenters = presenters
+      @sort_by = sort_by
+    end
+
+    def sorted_presenters
+      return @presenters if @sort_by.nil? || @sort_by.empty?
+      @presenters.sort do |presenter1, presenter2|
+        compare(presenter1, presenter2, @sort_by)
+      end
+    end
+
+    private
+
+    def compare(presenter1, presenter2, sort_by)
+      return 0 if sort_by.empty?
+      next_sort_by = sort_by.dup
+      field_name, direction = next_sort_by.shift
+
+      current_comparison =
+        presenter1.send(:field, field_name) <=> presenter2.send(:field, field_name)
+
+      if current_comparison == 0
+        compare(presenter1, presenter2, next_sort_by)
+      else
+        direction == :desc ? -current_comparison : current_comparison
+      end
+    end
+  end
+end

lib/aeolus_cli/provider.rb

@@ -7,7 +7,9 @@ class AeolusCli::Provider < AeolusCli::CommonCli
   method_options_for_resource_list
   def list
     providers = AeolusCli::Model::Provider.all
-    output_format.list(providers, resource_fields(options[:fields]))
+    output_format.list(providers,
+                       resource_fields(options[:fields]),
+                       resource_sort_by(options[:sort_by]))
   end
 
   desc "add PROVIDER_NAME", "Add a provider"

lib/aeolus_cli/provider_account.rb

@@ -8,7 +8,9 @@ class AeolusCli::ProviderAccount < AeolusCli::CommonCli
   # TODO maybe an optional variable for provider_type
   def list
     accounts = AeolusCli::Model::ProviderAccount.all_full_detail
-    output_format.list(accounts, resource_fields(options[:fields]))
+    output_format.list(accounts,
+                       resource_fields(options[:fields]),
+                       resource_sort_by(options[:sort_by]))
   end
 
   desc "add PROVIDER_ACCOUNT_LABEL", "Add a provider account"

spec/aeolus_cli/common_cli_spec.rb

@@ -21,4 +21,24 @@
       it { should == nil }
     end
   end
+
+  context "#resource_fields" do
+    context "non-empty fields" do
+      subject { common_cli.send(:resource_sort_by, "name+,status-,is_cool") }
+      it { should == [[:name, :asc], [:status, :desc], [:is_cool, :asc]] }
+    end
+
+    context "empty fields" do
+      subject { common_cli.send(:resource_sort_by, "") }
+      it do
+        expect { subject }.to raise_error Thor::MalformattedArgumentError
+      end
+    end
+
+    context "nil fields" do
+      subject { common_cli.send(:resource_sort_by, nil) }
+      it { should == nil }
+    end
+  end
+
 end

spec/aeolus_cli/formatting/format_spec.rb

@@ -7,7 +7,7 @@
 
   context "with a presenter" do
     let(:presenter) { double('presenter') }
-    let(:presenter_class) { double('presenter_class') }
+    let(:presenter_class) { double('presenter_class', :new => presenter) }
 
     before do
       format.register("String", presenter_class)
@@ -32,6 +32,20 @@
         subject.should == presenter
       end
     end
+
+    context "#presenters_for" do
+      let(:sorted_presenters) { double('sorted_presenters') }
+      let(:sorter) { double('sorter', :sorted_presenters => sorted_presenters) }
+      before do
+        AeolusCli::Formatting::PresenterSorter
+          .should_receive(:new)
+          .with([presenter, presenter], [:name, :asc])
+          .and_return(sorter)
+      end
+
+      subject { format.presenters_for(['one', 'two'], nil, [:name, :asc]) }
+      it { should == sorted_presenters }
+    end
   end
 
   context "printing methods" do

spec/aeolus_cli/formatting/human_format_spec.rb

@@ -30,17 +30,17 @@
 
   context "printing a list" do
     before do
-      format.stub_chain("presenter_for.list_item")
-        .and_return(['list', 'item'])
-      format.stub_chain("presenter_for.list_table_header")
-        .and_return(['table', 'header'])
+      format.stub("presenters_for").and_return([
+        double('first', :list_item => ['list', 'item'], :list_table_header => ['table', 'header']),
+        double('second', :list_item => ['list2', 'item2']),
+      ])
     end
 
     it "prints the data" do
       format.should_receive(:print_table).with([
                                                  ["table", "header"],
                                                  ["list", "item"],
-                                                 ["list", "item"],
+                                                 ["list2", "item2"],
                                                ])
 
       format.list(['a', 'b'])

spec/aeolus_cli/formatting/machine_format_spec.rb

@@ -24,12 +24,18 @@
 
   context "printing a list" do
     before do
-      format.stub_chain("presenter_for.list_item")
-        .and_return(['list', 'item'])
+      format.stub("presenters_for").and_return([
+        double('first', :list_item => ['list', 'item']),
+        double('second', :list_item => ['list2', 'item2']),
+      ])
     end
 
     it "prints the data" do
-      format.should_receive(:print).with("list;item").twice
+      format.should_receive(:print_list)
+            .with([
+                    ['list', 'item'],
+                    ['list2', 'item2'],
+                  ], ';')
 
       format.list(['a', 'b'])
     end

spec/aeolus_cli/formatting/presenter_sorter_spec.rb

@@ -0,0 +1,33 @@
+require 'aeolus_cli/formatting/presenter_sorter'
+
+describe AeolusCli::Formatting::PresenterSorter do
+
+  def stub_fields(presenter, status, owner)
+    presenter.stub(:field) do |param|
+      # If I could get local variable by name without using eval, I would :)
+      # Something like local_variable_get would be handy here.
+      case param
+      when :status
+        status
+      when :owner
+        owner
+      end
+    end
+  end
+
+  let(:p1) { double('p1').tap { |p| stub_fields(p, 'stopped', 'alice') } }
+  let(:p2) { double('p2').tap { |p| stub_fields(p, 'stopped', 'joe') } }
+  let(:p3) { double('p3').tap { |p| stub_fields(p, 'running', 'alice') } }
+  let(:p4) { double('p4').tap { |p| stub_fields(p, 'running', 'joe') } }
+
+  let(:presenters) { [p4, p1, p3, p2] }
+  let(:sorted_presenters) { [p1, p2, p3, p4] }
+  let(:sort_by) { [[:status, :desc], [:owner, :asc]] }
+  let(:sorter) { AeolusCli::Formatting::PresenterSorter.new(presenters, sort_by) }
+
+  context "#sorted_data" do
+    subject { sorter.sorted_presenters }
+
+    it { should == sorted_presenters }
+  end
+end