[Fix] variables_default_value_extraction sets type as not nullable wh…

…en variable is provided

examples/federation/products/graph/schema.graphqls

@@ -1,5 +1,5 @@
 extend type Query {
-    topProducts(first: Int = 5): [Product]
+    topProducts(first: Int! = 5): [Product]
 }
 
 extend type Subscription {
@@ -13,4 +13,4 @@ type Product @key(fields: "upc") {
     name: String!
     price: Int!
     inStock: Int!
-}
+}

pkg/astnormalization/variables_default_value_extraction.go

@@ -6,6 +6,7 @@ import (
 	"github.com/buger/jsonparser"
 	"github.com/tidwall/sjson"
 
+	"github.com/wundergraph/graphql-go-tools/internal/pkg/quotes"
 	"github.com/wundergraph/graphql-go-tools/internal/pkg/unsafebytes"
 	"github.com/wundergraph/graphql-go-tools/pkg/ast"
 	"github.com/wundergraph/graphql-go-tools/pkg/astimport"
@@ -81,25 +82,31 @@ func (v *variablesDefaultValueExtractionVisitor) EnterVariableDefinition(ref int
 	// remove variable DefaultValue from operation
 	v.operation.VariableDefinitions[ref].DefaultValue.IsDefined = false
 
-	// skip when variable was provided
-	_, _, _, err := jsonparser.Get(v.operation.Input.Variables, variableName)
-	if err == nil {
-		return
-	}
-
 	// store extracted variable ref
 	v.extractedVariablesRefs = append(v.extractedVariablesRefs, ref)
 
-	valueBytes, err := v.operation.ValueToJSON(v.operation.VariableDefinitionDefaultValue(ref))
-	if err != nil {
-		return
+	// Use the provided value for the variable if present, otherwise, use the default value
+	valueBytes, dataType, _, _:= jsonparser.Get(v.operation.Input.Variables, variableName)
+	if valueBytes == nil {
+		jsonVal, err := v.operation.ValueToJSON(v.operation.VariableDefinitionDefaultValue(ref))
+		if err != nil {
+			return
+		}
+
+		valueBytes = jsonVal
+	} else {
+		if dataType == jsonparser.String {
+			valueBytes = quotes.WrapBytes(valueBytes)
+		}
 	}
 
-	v.operation.Input.Variables, err = sjson.SetRawBytes(v.operation.Input.Variables, variableName, valueBytes)
+	inputVars, err := sjson.SetRawBytes(v.operation.Input.Variables, variableName, valueBytes)
 	if err != nil {
 		v.StopWithInternalErr(err)
 		return
 	}
+
+	v.operation.Input.Variables = inputVars
 }
 
 func (v *variablesDefaultValueExtractionVisitor) EnterOperationDefinition(ref int) {

pkg/astnormalization/variables_default_value_extraction_test.go

@@ -14,6 +14,8 @@ const (
 			objectInNestedList(input: [[Nested]]): String
 			stringInNestedList(input: [[String!]]): String
 			nullableStringInNestedList(input: [[String]]): String
+			notNullableInt(input: Int! = 5): String
+			notNullableString(input: String! = "DefaultInSchema"): String
 		}
 		input Nested {
 			NotNullable: String!
@@ -182,14 +184,14 @@ func TestVariablesDefaultValueExtraction(t *testing.T) {
 				runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
 					query q(
 						$nullable: String = "a",
-						$notNullable: String = "b",	
+						$notNullable: String = "b",
 					) {
 						objectInList(input: [{NotNullable: $notNullable, Nullable: $nullable}])
 					}`, "", `
-					query q(	
+					query q(
 						$nullable: String,
 						$notNullable: String!,
-					) {	
+					) {
 						objectInList(input: [{NotNullable: $notNullable, Nullable: $nullable}])
 					}`, ``, `{"notNullable":"b","nullable":"a"}`)
 			})
@@ -198,14 +200,14 @@ func TestVariablesDefaultValueExtraction(t *testing.T) {
 				runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
 					query q(
 						$nullable: String = "a",
-						$notNullable: String = "b",	
+						$notNullable: String = "b",
 					) {
 						objectInNestedList(input: [[{NotNullable: $notNullable, Nullable: $nullable}]])
 					}`, "", `
-					query q(	
+					query q(
 						$nullable: String,
 						$notNullable: String!,
-					) {	
+					) {
 						objectInNestedList(input: [[{NotNullable: $notNullable, Nullable: $nullable}]])
 					}`, ``, `{"notNullable":"b","nullable":"a"}`)
 			})
@@ -219,7 +221,7 @@ func TestVariablesDefaultValueExtraction(t *testing.T) {
 					}`, "", `
 					query q(
 						$notNullable: String!,
-					) {	
+					) {
 						stringInNestedList(input: [["a", $notNullable]])
 					}`, ``, `{"notNullable":"foo"}`)
 			})
@@ -233,7 +235,7 @@ func TestVariablesDefaultValueExtraction(t *testing.T) {
 					}`, "", `
 					query q(
 						$nullable: String,
-					) {	
+					) {
 						nullableStringInNestedList(input: [["a", null, $nullable]])
 					}`, ``, `{"nullable":"foo"}`)
 			})
@@ -264,6 +266,61 @@ func TestVariablesDefaultValueExtraction(t *testing.T) {
 			mutation simple($a: String, $b: String, $c: String, $d: String!) {
 				mixed(a: $a, b: $b, input: $c, nonNullInput: $d)
 			}`, `{"a":"aaa"}`, `{"d":"bar","c":"foo","b":"bazz","a":"aaa"}`)
+	})
+
+	t.Run("Not nullable int with default value", func(t *testing.T) {
+		runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
+			query q(
+				$input: Int = 4,
+			) {
+				notNullableInt(input: $input)
+			}`, "", `
+			query q(
+				$input: Int!,
+			) {
+				notNullableInt(input: $input)
+			}`, ``, `{"input":4}`)
+	})
 
+	t.Run("not nullable int with default value and variable overwrite", func(t *testing.T) {
+		runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
+			query q(
+				$input: Int = 4,
+			) {
+				notNullableInt(input: $input)
+			}`, "", `
+			query q(
+				$input: Int!,
+			) {
+				notNullableInt(input: $input)
+			}`, `{"input":6}`, `{"input":6}`)
+	})
+
+	t.Run("not nullable string with default value", func(t *testing.T) {
+		runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
+			query q(
+				$input: String = "DefaultInOperation",
+			) {
+				notNullableString(input: $input)
+			}`, "", `
+			query q(
+				$input: String!,
+			) {
+				notNullableString(input: $input)
+			}`, ``, `{"input":"DefaultInOperation"}`)
+	})
+
+	t.Run("not nullable string with default value and variable overwrite", func(t *testing.T) {
+		runWithVariablesDefaultValues(t, extractVariablesDefaultValue, variablesDefaultValueExtractionDefinition, `
+			query q(
+				$input: String = "DefaultInOperation",
+			) {
+				notNullableString(input: $input)
+			}`, "", `
+			query q(
+				$input: String!,
+			) {
+				notNullableString(input: $input)
+			}`, `{"input":"ValueInVariable"}`, `{"input":"ValueInVariable"}`)
 	})
 }