1 files changed, 103 insertions, 42 deletions

diff --git a/app/services/admin/set_feature_flag_service.rb b/app/services/admin/set_feature_flag_service.rb
index d72a18a6a58..3378be7eddd 100644
--- a/app/services/admin/set_feature_flag_service.rb
+++ b/app/services/admin/set_feature_flag_service.rb
@@ -2,82 +2,143 @@
 
 module Admin
   class SetFeatureFlagService
+    UnknownOperationError = Class.new(StandardError)
+
     def initialize(feature_flag_name:, params:)
       @name = feature_flag_name
+      @target = Feature::Target.new(params)
       @params = params
+      @force = params[:force]
     end
 
     def execute
-      unless params[:force]
+      unless force
         error = validate_feature_flag_name
         return ServiceResponse.error(message: error, reason: :invalid_feature_flag) if error
       end
 
-      flag_target = Feature::Target.new(params)
-      value = gate_value(params)
-
-      case value
-      when true
-        enable!(flag_target)
-      when false
-        disable!(flag_target)
+      if target.gate_specified?
+        update_targets
       else
-        enable_partially!(value, params)
+        update_global
       end
 
       feature_flag = Feature.get(name) # rubocop:disable Gitlab/AvoidFeatureGet
 
       ServiceResponse.success(payload: { feature_flag: feature_flag })
-    rescue Feature::Target::UnknowTargetError => e
+    rescue Feature::InvalidOperation => e
+      ServiceResponse.error(message: e.message, reason: :illegal_operation)
+    rescue UnknownOperationError => e
+      ServiceResponse.error(message: e.message, reason: :illegal_operation)
+    rescue Feature::Target::UnknownTargetError => e
       ServiceResponse.error(message: e.message, reason: :actor_not_found)
     end
 
     private
 
-    attr_reader :name, :params
+    attr_reader :name, :params, :target, :force
 
-    def enable!(flag_target)
-      if flag_target.gate_specified?
-        flag_target.targets.each { |target| Feature.enable(name, target) }
-      else
-        Feature.enable(name)
+    # Note: the if expressions in `update_targets` and `update_global` are order dependant.
+    def update_targets
+      target.targets.each do |target|
+        if enable?
+          enable(target)
+        elsif disable?
+          Feature.disable(name, target)
+        elsif opt_out?
+          Feature.opt_out(name, target)
+        elsif remove_opt_out?
+          remove_opt_out(target)
+        else
+          raise UnknownOperationError, "Cannot set '#{name}' to #{value.inspect} for #{target}"
+        end
       end
     end
 
-    def disable!(flag_target)
-      if flag_target.gate_specified?
-        flag_target.targets.each { |target| Feature.disable(name, target) }
-      else
+    def update_global
+      if enable?
+        Feature.enable(name)
+      elsif disable?
         Feature.disable(name)
+      elsif percentage_of_actors?
+        Feature.enable_percentage_of_actors(name, percentage)
+      elsif percentage_of_time?
+        Feature.enable_percentage_of_time(name, percentage)
+      else
+        msg = if key.present?
+                "Cannot set '#{name}' (#{key.inspect}) to #{value.inspect}"
+              else
+                "Cannot set '#{name}' to #{value.inspect}"
+              end
+
+        raise UnknownOperationError, msg
       end
     end
 
-    def enable_partially!(value, params)
-      if params[:key] == 'percentage_of_actors'
-        Feature.enable_percentage_of_actors(name, value)
-      else
-        Feature.enable_percentage_of_time(name, value)
+    def remove_opt_out(target)
+      raise Feature::InvalidOperation, "No opt-out exists for #{target}" unless Feature.opted_out?(name, target)
+
+      Feature.remove_opt_out(name, target)
+    end
+
+    def enable(target)
+      if Feature.opted_out?(name, target)
+        target_name = target.respond_to?(:to_reference) ? target.to_reference : target.to_s
+        raise Feature::InvalidOperation, "Opt-out exists for #{target_name} - remove opt-out before enabling"
       end
+
+      Feature.enable(name, target)
     end
 
-    def validate_feature_flag_name
-      # overridden in EE
+    def value
+      params[:value]
     end
 
-    def gate_value(params)
-      case params[:value]
-      when 'true'
-        true
-      when '0', 'false'
-        false
-      else
-        # https://github.com/jnunemaker/flipper/blob/master/lib/flipper/typecast.rb#L47
-        if params[:value].to_s.include?('.')
-          params[:value].to_f
-        else
-          params[:value].to_i
-        end
-      end
+    def key
+      params[:key]
+    end
+
+    def numeric_value?
+      params[:value].match?(/^\d+(\.\d+)?$/)
+    end
+
+    def percentage
+      raise UnknownOperationError, "Not a percentage" unless numeric_value?
+
+      value.to_f
+    end
+
+    def percentage_of_actors?
+      key == 'percentage_of_actors'
+    end
+
+    def percentage_of_time?
+      return true if key == 'percentage_of_time'
+      return numeric_value? if key.nil?
+
+      false
+    end
+
+    # Note: `key` is NOT considered - setting to a percentage to 0 is the same as disabling.
+    def disable?
+      value.in?(%w[0 0.0 false])
+    end
+
+    # Note: `key` is NOT considered - setting to a percentage to 100 is the same
+    def enable?
+      value.in?(%w[100 100.0 true])
+    end
+
+    def opt_out?
+      value == 'opt_out'
+    end
+
+    def remove_opt_out?
+      value == 'remove_opt_out'
+    end
+
+    def validate_feature_flag_name
+      ## Overridden in EE
     end
   end
 end