Rename "Slash commands" to "Quick actions"

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/27070

Deprecate "chat commands" in favor of "slash commands"

We looked for things like:

 - `slash commmand`
 - `slash_command`
 - `slash-command`
 - `SlashCommand`

20 files changed, 641 insertions, 351 deletions

diff --git a/lib/gitlab/slash_commands/base_command.rb b/lib/gitlab/slash_commands/base_command.rb
new file mode 100644
index 00000000000..cc3c9a50555
--- /dev/null
+++ b/lib/gitlab/slash_commands/base_command.rb
@@ -0,0 +1,47 @@
+module Gitlab
+  module SlashCommands
+    class BaseCommand
+      QUERY_LIMIT = 5
+
+      def self.match(_text)
+        raise NotImplementedError
+      end
+
+      def self.help_message
+        raise NotImplementedError
+      end
+
+      def self.available?(_project)
+        raise NotImplementedError
+      end
+
+      def self.allowed?(_user, _ability)
+        true
+      end
+
+      def self.can?(object, action, subject)
+        Ability.allowed?(object, action, subject)
+      end
+
+      def execute(_)
+        raise NotImplementedError
+      end
+
+      def collection
+        raise NotImplementedError
+      end
+
+      attr_accessor :project, :current_user, :params
+
+      def initialize(project, user, params = {})
+        @project, @current_user, @params = project, user, params.dup
+      end
+
+      private
+
+      def find_by_iid(iid)
+        collection.find_by(iid: iid)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/command.rb b/lib/gitlab/slash_commands/command.rb
new file mode 100644
index 00000000000..a78408b0519
--- /dev/null
+++ b/lib/gitlab/slash_commands/command.rb
@@ -0,0 +1,44 @@
+module Gitlab
+  module SlashCommands
+    class Command < BaseCommand
+      COMMANDS = [
+        Gitlab::SlashCommands::IssueShow,
+        Gitlab::SlashCommands::IssueNew,
+        Gitlab::SlashCommands::IssueSearch,
+        Gitlab::SlashCommands::Deploy
+      ].freeze
+
+      def execute
+        command, match = match_command
+
+        if command
+          if command.allowed?(project, current_user)
+            command.new(project, current_user, params).execute(match)
+          else
+            Gitlab::SlashCommands::Presenters::Access.new.access_denied
+          end
+        else
+          Gitlab::SlashCommands::Help.new(project, current_user, params).execute(available_commands, params[:text])
+        end
+      end
+
+      def match_command
+        match = nil
+        service =
+          available_commands.find do |klass|
+            match = klass.match(params[:text])
+          end
+
+        [service, match]
+      end
+
+      private
+
+      def available_commands
+        COMMANDS.select do |klass|
+          klass.available?(project)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/command_definition.rb b/lib/gitlab/slash_commands/command_definition.rb
deleted file mode 100644
index caab8856014..00000000000
--- a/lib/gitlab/slash_commands/command_definition.rb
+++ /dev/null
@@ -1,89 +0,0 @@
-module Gitlab
-  module SlashCommands
-    class CommandDefinition
-      attr_accessor :name, :aliases, :description, :explanation, :params,
-        :condition_block, :parse_params_block, :action_block
-
-      def initialize(name, attributes = {})
-        @name = name
-
-        @aliases = attributes[:aliases] || []
-        @description = attributes[:description] || ''
-        @explanation = attributes[:explanation] || ''
-        @params = attributes[:params] || []
-        @condition_block = attributes[:condition_block]
-        @parse_params_block = attributes[:parse_params_block]
-        @action_block = attributes[:action_block]
-      end
-
-      def all_names
-        [name, *aliases]
-      end
-
-      def noop?
-        action_block.nil?
-      end
-
-      def available?(opts)
-        return true unless condition_block
-
-        context = OpenStruct.new(opts)
-        context.instance_exec(&condition_block)
-      end
-
-      def explain(context, opts, arg)
-        return unless available?(opts)
-
-        if explanation.respond_to?(:call)
-          execute_block(explanation, context, arg)
-        else
-          explanation
-        end
-      end
-
-      def execute(context, opts, arg)
-        return if noop? || !available?(opts)
-
-        execute_block(action_block, context, arg)
-      end
-
-      def to_h(opts)
-        context = OpenStruct.new(opts)
-
-        desc = description
-        if desc.respond_to?(:call)
-          desc = context.instance_exec(&desc) rescue ''
-        end
-
-        prms = params
-        if prms.respond_to?(:call)
-          prms = Array(context.instance_exec(&prms)) rescue params
-        end
-
-        {
-          name: name,
-          aliases: aliases,
-          description: desc,
-          params: prms
-        }
-      end
-
-      private
-
-      def execute_block(block, context, arg)
-        if arg.present?
-          parsed = parse_params(arg, context)
-          context.instance_exec(parsed, &block)
-        elsif block.arity == 0
-          context.instance_exec(&block)
-        end
-      end
-
-      def parse_params(arg, context)
-        return arg unless parse_params_block
-
-        context.instance_exec(arg, &parse_params_block)
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/slash_commands/deploy.rb b/lib/gitlab/slash_commands/deploy.rb
new file mode 100644
index 00000000000..e71eb15d604
--- /dev/null
+++ b/lib/gitlab/slash_commands/deploy.rb
@@ -0,0 +1,50 @@
+module Gitlab
+  module SlashCommands
+    class Deploy < BaseCommand
+      def self.match(text)
+        /\Adeploy\s+(?<from>\S+.*)\s+to+\s+(?<to>\S+.*)\z/.match(text)
+      end
+
+      def self.help_message
+        'deploy <environment> to <target-environment>'
+      end
+
+      def self.available?(project)
+        project.builds_enabled?
+      end
+
+      def self.allowed?(project, user)
+        can?(user, :create_deployment, project)
+      end
+
+      def execute(match)
+        from = match[:from]
+        to = match[:to]
+
+        actions = find_actions(from, to)
+
+        if actions.none?
+          Gitlab::SlashCommands::Presenters::Deploy.new(nil).no_actions
+        elsif actions.one?
+          action = play!(from, to, actions.first)
+          Gitlab::SlashCommands::Presenters::Deploy.new(action).present(from, to)
+        else
+          Gitlab::SlashCommands::Presenters::Deploy.new(actions).too_many_actions
+        end
+      end
+
+      private
+
+      def play!(from, to, action)
+        action.play(current_user)
+      end
+
+      def find_actions(from, to)
+        environment = project.environments.find_by(name: from)
+        return [] unless environment
+
+        environment.actions_for(to).select(&:starts_environment?)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/dsl.rb b/lib/gitlab/slash_commands/dsl.rb
deleted file mode 100644
index 1b5b4566d81..00000000000
--- a/lib/gitlab/slash_commands/dsl.rb
+++ /dev/null
@@ -1,140 +0,0 @@
-module Gitlab
-  module SlashCommands
-    module Dsl
-      extend ActiveSupport::Concern
-
-      included do
-        cattr_accessor :command_definitions, instance_accessor: false do
-          []
-        end
-
-        cattr_accessor :command_definitions_by_name, instance_accessor: false do
-          {}
-        end
-      end
-
-      class_methods do
-        # Allows to give a description to the next slash command.
-        # This description is shown in the autocomplete menu.
-        # It accepts a block that will be evaluated with the context given to
-        # `CommandDefintion#to_h`.
-        #
-        # Example:
-        #
-        #   desc do
-        #     "This is a dynamic description for #{noteable.to_ability_name}"
-        #   end
-        #   command :command_key do |arguments|
-        #     # Awesome code block
-        #   end
-        def desc(text = '', &block)
-          @description = block_given? ? block : text
-        end
-
-        # Allows to define params for the next slash command.
-        # These params are shown in the autocomplete menu.
-        #
-        # Example:
-        #
-        #   params "~label ~label2"
-        #   command :command_key do |arguments|
-        #     # Awesome code block
-        #   end
-        def params(*params, &block)
-          @params = block_given? ? block : params
-        end
-
-        # Allows to give an explanation of what the command will do when
-        # executed. This explanation is shown when rendering the Markdown
-        # preview.
-        #
-        # Example:
-        #
-        #   explanation do |arguments|
-        #     "Adds label(s) #{arguments.join(' ')}"
-        #   end
-        #   command :command_key do |arguments|
-        #     # Awesome code block
-        #   end
-        def explanation(text = '', &block)
-          @explanation = block_given? ? block : text
-        end
-
-        # Allows to define conditions that must be met in order for the command
-        # to be returned by `.command_names` & `.command_definitions`.
-        # It accepts a block that will be evaluated with the context given to
-        # `CommandDefintion#to_h`.
-        #
-        # Example:
-        #
-        #   condition do
-        #     project.public?
-        #   end
-        #   command :command_key do |arguments|
-        #     # Awesome code block
-        #   end
-        def condition(&block)
-          @condition_block = block
-        end
-
-        # Allows to perform initial parsing of parameters. The result is passed
-        # both to `command` and `explanation` blocks, instead of the raw
-        # parameters.
-        # It accepts a block that will be evaluated with the context given to
-        # `CommandDefintion#to_h`.
-        #
-        # Example:
-        #
-        #   parse_params do |raw|
-        #     raw.strip
-        #   end
-        #   command :command_key do |parsed|
-        #     # Awesome code block
-        #   end
-        def parse_params(&block)
-          @parse_params_block = block
-        end
-
-        # Registers a new command which is recognizeable from body of email or
-        # comment.
-        # It accepts aliases and takes a block.
-        #
-        # Example:
-        #
-        #   command :my_command, :alias_for_my_command do |arguments|
-        #     # Awesome code block
-        #   end
-        def command(*command_names, &block)
-          name, *aliases = command_names
-
-          definition = CommandDefinition.new(
-            name,
-            aliases: aliases,
-            description: @description,
-            explanation: @explanation,
-            params: @params,
-            condition_block: @condition_block,
-            parse_params_block: @parse_params_block,
-            action_block: block
-          )
-
-          self.command_definitions << definition
-
-          definition.all_names.each do |name|
-            self.command_definitions_by_name[name] = definition
-          end
-
-          @description = nil
-          @explanation = nil
-          @params = nil
-          @condition_block = nil
-          @parse_params_block = nil
-        end
-
-        def definition_by_name(name)
-          command_definitions_by_name[name.to_sym]
-        end
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/slash_commands/extractor.rb b/lib/gitlab/slash_commands/extractor.rb
deleted file mode 100644
index 6dbb467d70d..00000000000
--- a/lib/gitlab/slash_commands/extractor.rb
+++ /dev/null
@@ -1,122 +0,0 @@
-module Gitlab
-  module SlashCommands
-    # This class takes an array of commands that should be extracted from a
-    # given text.
-    #
-    # ```
-    # extractor = Gitlab::SlashCommands::Extractor.new([:open, :assign, :labels])
-    # ```
-    class Extractor
-      attr_reader :command_definitions
-
-      def initialize(command_definitions)
-        @command_definitions = command_definitions
-      end
-
-      # Extracts commands from content and return an array of commands.
-      # The array looks like the following:
-      # [
-      #   ['command1'],
-      #   ['command3', 'arg1 arg2'],
-      # ]
-      # The command and the arguments are stripped.
-      # The original command text is removed from the given `content`.
-      #
-      # Usage:
-      # ```
-      # extractor = Gitlab::SlashCommands::Extractor.new([:open, :assign, :labels])
-      # msg = %(hello\n/labels ~foo ~"bar baz"\nworld)
-      # commands = extractor.extract_commands(msg) #=> [['labels', '~foo ~"bar baz"']]
-      # msg #=> "hello\nworld"
-      # ```
-      def extract_commands(content, opts = {})
-        return [content, []] unless content
-
-        content = content.dup
-
-        commands = []
-
-        content.delete!("\r")
-        content.gsub!(commands_regex(opts)) do
-          if $~[:cmd]
-            commands << [$~[:cmd], $~[:arg]].reject(&:blank?)
-            ''
-          else
-            $~[0]
-          end
-        end
-
-        [content.strip, commands]
-      end
-
-      private
-
-      # Builds a regular expression to match known commands.
-      # First match group captures the command name and
-      # second match group captures its arguments.
-      #
-      # It looks something like:
-      #
-      #   /^\/(?<cmd>close|reopen|...)(?:( |$))(?<arg>[^\/\n]*)(?:\n|$)/
-      def commands_regex(opts)
-        names = command_names(opts).map(&:to_s)
-
-        @commands_regex ||= %r{
-            (?<code>
-              # Code blocks:
-              # ```
-              # Anything, including `/cmd arg` which are ignored by this filter
-              # ```
-
-              ^```
-              .+?
-              \n```$
-            )
-          |
-            (?<html>
-              # HTML block:
-              # <tag>
-              # Anything, including `/cmd arg` which are ignored by this filter
-              # </tag>
-
-              ^<[^>]+?>\n
-              .+?
-              \n<\/[^>]+?>$
-            )
-          |
-            (?<html>
-              # Quote block:
-              # >>>
-              # Anything, including `/cmd arg` which are ignored by this filter
-              # >>>
-
-              ^>>>
-              .+?
-              \n>>>$
-            )
-          |
-            (?:
-              # Command not in a blockquote, blockcode, or HTML tag:
-              # /close
-
-              ^\/
-              (?<cmd>#{Regexp.union(names)})
-              (?:
-                [ ]
-                (?<arg>[^\n]*)
-              )?
-              (?:\n|$)
-            )
-        }mx
-      end
-
-      def command_names(opts)
-        command_definitions.flat_map do |command|
-          next if command.noop?
-
-          command.all_names
-        end.compact
-      end
-    end
-  end
-end
diff --git a/lib/gitlab/slash_commands/help.rb b/lib/gitlab/slash_commands/help.rb
new file mode 100644
index 00000000000..81f3707e03e
--- /dev/null
+++ b/lib/gitlab/slash_commands/help.rb
@@ -0,0 +1,28 @@
+module Gitlab
+  module SlashCommands
+    class Help < BaseCommand
+      # This class has to be used last, as it always matches. It has to match
+      # because other commands were not triggered and we want to show the help
+      # command
+      def self.match(_text)
+        true
+      end
+
+      def self.help_message
+        'help'
+      end
+
+      def self.allowed?(_project, _user)
+        true
+      end
+
+      def execute(commands, text)
+        Gitlab::SlashCommands::Presenters::Help.new(commands).present(trigger, text)
+      end
+
+      def trigger
+        params[:command]
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/issue_command.rb b/lib/gitlab/slash_commands/issue_command.rb
new file mode 100644
index 00000000000..87ea19b8806
--- /dev/null
+++ b/lib/gitlab/slash_commands/issue_command.rb
@@ -0,0 +1,13 @@
+module Gitlab
+  module SlashCommands
+    class IssueCommand < BaseCommand
+      def self.available?(project)
+        project.issues_enabled? && project.default_issues_tracker?
+      end
+
+      def collection
+        IssuesFinder.new(current_user, project_id: project.id).execute
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/issue_new.rb b/lib/gitlab/slash_commands/issue_new.rb
new file mode 100644
index 00000000000..25f965e843d
--- /dev/null
+++ b/lib/gitlab/slash_commands/issue_new.rb
@@ -0,0 +1,42 @@
+module Gitlab
+  module SlashCommands
+    class IssueNew < IssueCommand
+      def self.match(text)
+        # we can not match \n with the dot by passing the m modifier as than
+        # the title and description are not seperated
+        /\Aissue\s+(new|create)\s+(?<title>[^\n]*)\n*(?<description>(.|\n)*)/.match(text)
+      end
+
+      def self.help_message
+        'issue new <title> *`⇧ Shift`*+*`↵ Enter`* <description>'
+      end
+
+      def self.allowed?(project, user)
+        can?(user, :create_issue, project)
+      end
+
+      def execute(match)
+        title = match[:title]
+        description = match[:description].to_s.rstrip
+
+        issue = create_issue(title: title, description: description)
+
+        if issue.persisted?
+          presenter(issue).present
+        else
+          presenter(issue).display_errors
+        end
+      end
+
+      private
+
+      def create_issue(title:, description:)
+        Issues::CreateService.new(project, current_user, title: title, description: description).execute
+      end
+
+      def presenter(issue)
+        Gitlab::SlashCommands::Presenters::IssueNew.new(issue)
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/issue_search.rb b/lib/gitlab/slash_commands/issue_search.rb
new file mode 100644
index 00000000000..acba84b54b4
--- /dev/null
+++ b/lib/gitlab/slash_commands/issue_search.rb
@@ -0,0 +1,23 @@
+module Gitlab
+  module SlashCommands
+    class IssueSearch < IssueCommand
+      def self.match(text)
+        /\Aissue\s+search\s+(?<query>.*)/.match(text)
+      end
+
+      def self.help_message
+        "issue search <your query>"
+      end
+
+      def execute(match)
+        issues = collection.search(match[:query]).limit(QUERY_LIMIT)
+
+        if issues.present?
+          Presenters::IssueSearch.new(issues).present
+        else
+          Presenters::Access.new(issues).not_found
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/issue_show.rb b/lib/gitlab/slash_commands/issue_show.rb
new file mode 100644
index 00000000000..ffa5184e5cb
--- /dev/null
+++ b/lib/gitlab/slash_commands/issue_show.rb
@@ -0,0 +1,23 @@
+module Gitlab
+  module SlashCommands
+    class IssueShow < IssueCommand
+      def self.match(text)
+        /\Aissue\s+show\s+#{Issue.reference_prefix}?(?<iid>\d+)/.match(text)
+      end
+
+      def self.help_message
+        "issue show <id>"
+      end
+
+      def execute(match)
+        issue = find_by_iid(match[:iid])
+
+        if issue
+          Gitlab::SlashCommands::Presenters::IssueShow.new(issue).present
+        else
+          Gitlab::SlashCommands::Presenters::Access.new.not_found
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/access.rb b/lib/gitlab/slash_commands/presenters/access.rb
new file mode 100644
index 00000000000..1a817eb735b
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/access.rb
@@ -0,0 +1,40 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class Access < Presenters::Base
+        def access_denied
+          ephemeral_response(text: "Whoops! This action is not allowed. This incident will be [reported](https://xkcd.com/838/).")
+        end
+
+        def not_found
+          ephemeral_response(text: "404 not found! GitLab couldn't find what you were looking for! :boom:")
+        end
+
+        def authorize
+          message =
+            if @resource
+              ":wave: Hi there! Before I do anything for you, please [connect your GitLab account](#{@resource})."
+            else
+              ":sweat_smile: Couldn't identify you, nor can I autorize you!"
+            end
+
+          ephemeral_response(text: message)
+        end
+
+        def unknown_command(commands)
+          ephemeral_response(text: help_message(trigger))
+        end
+
+        private
+
+        def help_message(trigger)
+          header_with_list("Command not found, these are the commands you can use", full_commands(trigger))
+        end
+
+        def full_commands(trigger)
+          @resource.map { |command| "#{trigger} #{command.help_message}" }
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/base.rb b/lib/gitlab/slash_commands/presenters/base.rb
new file mode 100644
index 00000000000..27696436574
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/base.rb
@@ -0,0 +1,77 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class Base
+        include Gitlab::Routing.url_helpers
+
+        def initialize(resource = nil)
+          @resource = resource
+        end
+
+        def display_errors
+          message = header_with_list("The action was not successful, because:", @resource.errors.full_messages)
+
+          ephemeral_response(text: message)
+        end
+
+        private
+
+        def header_with_list(header, items)
+          message = [header]
+
+          items.each do |item|
+            message << "- #{item}"
+          end
+
+          message.join("\n")
+        end
+
+        def ephemeral_response(message)
+          response = {
+            response_type: :ephemeral,
+            status: 200
+          }.merge(message)
+
+          format_response(response)
+        end
+
+        def in_channel_response(message)
+          response = {
+            response_type: :in_channel,
+            status: 200
+          }.merge(message)
+
+          format_response(response)
+        end
+
+        def format_response(response)
+          response[:text] = format(response[:text]) if response.key?(:text)
+
+          if response.key?(:attachments)
+            response[:attachments].each do |attachment|
+              attachment[:pretext] = format(attachment[:pretext]) if attachment[:pretext]
+              attachment[:text] = format(attachment[:text]) if attachment[:text]
+            end
+          end
+
+          response
+        end
+
+        # Convert Markdown to slacks format
+        def format(string)
+          Slack::Notifier::LinkFormatter.format(string)
+        end
+
+        def resource_url
+          url_for(
+            [
+              @resource.project.namespace.becomes(Namespace),
+              @resource.project,
+              @resource
+            ]
+          )
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/deploy.rb b/lib/gitlab/slash_commands/presenters/deploy.rb
new file mode 100644
index 00000000000..b8dc77bd37b
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/deploy.rb
@@ -0,0 +1,21 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class Deploy < Presenters::Base
+        def present(from, to)
+          message = "Deployment started from #{from} to #{to}. [Follow its progress](#{resource_url})."
+
+          in_channel_response(text: message)
+        end
+
+        def no_actions
+          ephemeral_response(text: "No action found to be executed")
+        end
+
+        def too_many_actions
+          ephemeral_response(text: "Too many actions defined")
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/help.rb b/lib/gitlab/slash_commands/presenters/help.rb
new file mode 100644
index 00000000000..ea611a4d629
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/help.rb
@@ -0,0 +1,27 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class Help < Presenters::Base
+        def present(trigger, text)
+          ephemeral_response(text: help_message(trigger, text))
+        end
+
+        private
+
+        def help_message(trigger, text)
+          return "No commands available :thinking_face:" unless @resource.present?
+
+          if text.start_with?('help')
+            header_with_list("Available commands", full_commands(trigger))
+          else
+            header_with_list("Unknown command, these commands are available", full_commands(trigger)) 
+          end
+        end
+
+        def full_commands(trigger)
+          @resource.map { |command| "#{trigger} #{command.help_message}" }
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/issue_base.rb b/lib/gitlab/slash_commands/presenters/issue_base.rb
new file mode 100644
index 00000000000..341f2aabdd0
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/issue_base.rb
@@ -0,0 +1,43 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      module IssueBase
+        def color(issuable)
+          issuable.open? ? '#38ae67' : '#d22852'
+        end
+
+        def status_text(issuable)
+          issuable.open? ? 'Open' : 'Closed'
+        end
+
+        def project
+          @resource.project
+        end
+
+        def author
+          @resource.author
+        end
+
+        def fields
+          [
+            {
+              title: "Assignee",
+              value: @resource.assignees.any? ? @resource.assignees.first.name : "_None_",
+              short: true
+            },
+            {
+              title: "Milestone",
+              value: @resource.milestone ? @resource.milestone.title : "_None_",
+              short: true
+            },
+            {
+              title: "Labels",
+              value: @resource.labels.any? ? @resource.label_names.join(', ') : "_None_",
+              short: true
+            }
+          ]
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/issue_new.rb b/lib/gitlab/slash_commands/presenters/issue_new.rb
new file mode 100644
index 00000000000..86490a39cc1
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/issue_new.rb
@@ -0,0 +1,50 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class IssueNew < Presenters::Base
+        include Presenters::IssueBase
+
+        def present
+          in_channel_response(new_issue)
+        end
+
+        private
+
+        def new_issue
+          {
+            attachments: [
+              {
+                title:        "#{@resource.title} · #{@resource.to_reference}",
+                title_link:   resource_url,
+                author_name:  author.name,
+                author_icon:  author.avatar_url,
+                fallback:     "New issue #{@resource.to_reference}: #{@resource.title}",
+                pretext:      pretext,
+                color:        color(@resource),
+                fields:       fields,
+                mrkdwn_in: [
+                  :title,
+                  :pretext,
+                  :text,
+                  :fields
+                ]
+              }
+            ]
+          }
+        end
+
+        def pretext
+          "I created an issue on #{author_profile_link}'s behalf: **#{@resource.to_reference}** in #{project_link}"
+        end
+
+        def project_link
+          "[#{project.name_with_namespace}](#{project.web_url})"
+        end
+
+        def author_profile_link
+          "[#{author.to_reference}](#{url_for(author)})"
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/issue_search.rb b/lib/gitlab/slash_commands/presenters/issue_search.rb
new file mode 100644
index 00000000000..4e27d668685
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/issue_search.rb
@@ -0,0 +1,47 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class IssueSearch < Presenters::Base
+        include Presenters::IssueBase
+
+        def present
+          text = if @resource.count >= 5
+                   "Here are the first 5 issues I found:"
+                 elsif @resource.one?
+                   "Here is the only issue I found:"
+                 else
+                   "Here are the #{@resource.count} issues I found:"
+                 end
+
+          ephemeral_response(text: text, attachments: attachments)
+        end
+
+        private
+
+        def attachments
+          @resource.map do |issue|
+            url = "[#{issue.to_reference}](#{url_for([namespace, project, issue])})"
+
+            {
+              color: color(issue),
+              fallback: "#{issue.to_reference} #{issue.title}",
+              text: "#{url} · #{issue.title} (#{status_text(issue)})",
+
+              mrkdwn_in: [
+                :text
+              ]
+            }
+          end
+        end
+
+        def project
+          @project ||= @resource.first.project
+        end
+
+        def namespace
+          @namespace ||= project.namespace.becomes(Namespace)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/presenters/issue_show.rb b/lib/gitlab/slash_commands/presenters/issue_show.rb
new file mode 100644
index 00000000000..c99316df667
--- /dev/null
+++ b/lib/gitlab/slash_commands/presenters/issue_show.rb
@@ -0,0 +1,61 @@
+module Gitlab
+  module SlashCommands
+    module Presenters
+      class IssueShow < Presenters::Base
+        include Presenters::IssueBase
+
+        def present
+          if @resource.confidential?
+            ephemeral_response(show_issue)
+          else
+            in_channel_response(show_issue)
+          end
+        end
+
+        private
+
+        def show_issue
+          {
+            attachments: [
+              {
+                title:        "#{@resource.title} · #{@resource.to_reference}",
+                title_link:   resource_url,
+                author_name:  author.name,
+                author_icon:  author.avatar_url,
+                fallback:     "Issue #{@resource.to_reference}: #{@resource.title}",
+                pretext:      pretext,
+                text:         text,
+                color:        color(@resource),
+                fields:       fields,
+                mrkdwn_in: [
+                  :pretext,
+                  :text,
+                  :fields
+                ]
+              }
+            ]
+          }
+        end
+
+        def text
+          message = "**#{status_text(@resource)}**"
+
+          if @resource.upvotes.zero? && @resource.downvotes.zero? && @resource.user_notes_count.zero?
+            return message
+          end
+
+          message << " · "
+          message << ":+1: #{@resource.upvotes} " unless @resource.upvotes.zero?
+          message << ":-1: #{@resource.downvotes} " unless @resource.downvotes.zero?
+          message << ":speech_balloon: #{@resource.user_notes_count}" unless @resource.user_notes_count.zero?
+
+          message
+        end
+
+        def pretext
+          "Issue *#{@resource.to_reference}* from #{project.name_with_namespace}"
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/result.rb b/lib/gitlab/slash_commands/result.rb
new file mode 100644
index 00000000000..7021b4b01b2
--- /dev/null
+++ b/lib/gitlab/slash_commands/result.rb
@@ -0,0 +1,5 @@
+module Gitlab
+  module SlashCommands
+    Result = Struct.new(:type, :message)
+  end
+end