Do not serialize empty lists in ec2 protocol (#3017)

Author: jterapin

build_tools/aws-sdk-code-generator/spec/protocol-tests-ignore-list.json

@@ -1,7 +1,11 @@
 {
   "ec2" :
     {
-      "input" : [],
+      "input" : [
+        {
+          "Ec2EmptyQueryLists": "Empty lists should be omitted from serialization. Smithy to update"
+        }
+      ],
       "output" : []
     },
   "json" : {

gems/aws-sdk-core/CHANGELOG.md

@@ -1,6 +1,8 @@
 Unreleased Changes
 ------------------
 
+* Issue - Update EC2 protocol to not serialize empty lists.
+
 3.194.0 (2024-04-30)
 ------------------
 

gems/aws-sdk-core/lib/aws-sdk-core/query/ec2_param_builder.rb

@@ -31,13 +31,11 @@ def structure(ref, values, prefix)
       end
 
       def list(ref, values, prefix)
-        if values.empty?
-          set(prefix, '')
-        else
-          member_ref = ref.shape.member
-          values.each.with_index do |value, n|
-            format(member_ref, value, "#{prefix}.#{n+1}")
-          end
+        return if values.empty?
+
+        member_ref = ref.shape.member
+        values.each.with_index do |value, n|
+          format(member_ref, value, "#{prefix}.#{n + 1}")
         end
       end
 

gems/aws-sdk-core/spec/aws/query/ec2_param_builder_spec.rb

@@ -5,33 +5,52 @@
 module Aws
   module Query
     describe EC2ParamBuilder do
-
       let(:shapes) { ApiHelper.sample_shapes }
 
-      let(:rules) {
-        ApiHelper.sample_api(shapes:shapes).
-          operation(:example_operation).
-          input
-      }
+      let(:rules) do
+        ApiHelper
+          .sample_api(shapes: shapes)
+          .operation(:example_operation)
+          .input
+      end
 
       def query(params = {})
         param_list = ParamList.new
         EC2ParamBuilder.new(param_list).apply(rules, params)
-        param_list.map { |param| [param.name, param.value ] }.sort
+        param_list.map { |param| [param.name, param.value] }.sort
       end
 
       it 'can serialize structures' do
         params = Structure.new(*rules.shape.member_names).new
         params.boolean = true
         params.integer = 123
         params.string = 'abc'
-        expect(query(params)).to eq([
-          ['Boolean', 'true'],
-          ['Integer', '123'],
-          ['String', 'abc'],
-        ])
+        expect(query(params)).to eq(
+          [
+            %w[Boolean true],
+            %w[Integer 123],
+            %w[String abc]
+          ]
+        )
       end
 
+      it 'can serialize non-empty lists' do
+        params = Structure.new(*rules.shape.member_names).new
+        params.number_list = [1, 2, 3]
+        expect(query(params)).to eq(
+          [
+            %w[NumberList.1 1],
+            %w[NumberList.2 2],
+            %w[NumberList.3 3]
+          ]
+        )
+      end
+
+      it 'does not serialize empty lists' do
+        params = Structure.new(*rules.shape.member_names).new
+        params.number_list = []
+        expect(query(params)).to be_empty
+      end
     end
   end
 end