fix: handle boolean false for UrlPattern and UrlPrefix in ContentTypeOptions

management/content_type.go

@@ -37,13 +37,32 @@ type ContentTypeInput struct {
 }
 
 type ContentTypeOptions struct {
-	Title       string   `json:"title"`
-	Publishable bool     `json:"bool"`
-	IsPage      bool     `json:"is_page"`
-	Singleton   bool     `json:"singleton"`
-	SubTitle    []string `json:"sub_title"`
-	UrlPattern  string   `json:"url_pattern"`
-	UrlPrefix   string   `json:"url_prefix"`
+	Title       string     `json:"title"`
+	Publishable bool       `json:"bool"`
+	IsPage      bool       `json:"is_page"`
+	Singleton   bool       `json:"singleton"`
+	SubTitle    []string   `json:"sub_title"`
+	UrlPattern  FlexString `json:"url_pattern"`
+	UrlPrefix   FlexString `json:"url_prefix"`
+}
+
+// FlexString unmarshals a JSON value that is either a string or a boolean.
+// The Contentstack API returns false (boolean) for string fields that are unset,
+// rather than omitting them or returning an empty string.
+type FlexString string
+
+func (f *FlexString) UnmarshalJSON(data []byte) error {
+	var s string
+	if err := json.Unmarshal(data, &s); err == nil {
+		*f = FlexString(s)
+		return nil
+	}
+	var b bool
+	if err := json.Unmarshal(data, &b); err == nil {
+		*f = ""
+		return nil
+	}
+	return fmt.Errorf("FlexString: cannot unmarshal %s into string or bool", data)
 }
 
 func (si *StackInstance) ContentTypeCreate(ctx context.Context, input ContentTypeInput) (*ContentType, error) {

management/content_type_test.go

@@ -0,0 +1,124 @@
+package management
+
+import (
+	"encoding/json"
+	"testing"
+)
+
+func TestFlexString_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		name    string
+		input   string
+		want    FlexString
+		wantErr bool
+	}{
+		{
+			name:  "string value",
+			input: `"/:title"`,
+			want:  "/:title",
+		},
+		{
+			name:  "empty string",
+			input: `""`,
+			want:  "",
+		},
+		{
+			name:  "boolean false treated as empty string",
+			input: `false`,
+			want:  "",
+		},
+		{
+			name:  "boolean true treated as empty string",
+			input: `true`,
+			want:  "",
+		},
+		{
+			name:    "number is invalid",
+			input:   `42`,
+			wantErr: true,
+		},
+		{
+			// JSON null unmarshals into bool as false in Go, so null is treated
+			// as empty string rather than an error.
+			name:  "null treated as empty string",
+			input: `null`,
+			want:  "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var f FlexString
+			err := json.Unmarshal([]byte(tt.input), &f)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("UnmarshalJSON() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !tt.wantErr && f != tt.want {
+				t.Errorf("UnmarshalJSON() = %q, want %q", f, tt.want)
+			}
+		})
+	}
+}
+
+func TestContentTypeOptions_UnmarshalJSON(t *testing.T) {
+	t.Run("url_pattern and url_prefix as strings", func(t *testing.T) {
+		input := `{
+			"title": "My Type",
+			"is_page": true,
+			"singleton": false,
+			"url_pattern": "/:title",
+			"url_prefix": "/"
+		}`
+		var opts ContentTypeOptions
+		if err := json.Unmarshal([]byte(input), &opts); err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if opts.UrlPattern != "/:title" {
+			t.Errorf("UrlPattern = %q, want %q", opts.UrlPattern, "/:title")
+		}
+		if opts.UrlPrefix != "/" {
+			t.Errorf("UrlPrefix = %q, want %q", opts.UrlPrefix, "/")
+		}
+	})
+
+	t.Run("url_pattern and url_prefix as boolean false (unset)", func(t *testing.T) {
+		input := `{
+			"title": "My Type",
+			"is_page": false,
+			"singleton": false,
+			"url_pattern": false,
+			"url_prefix": false
+		}`
+		var opts ContentTypeOptions
+		if err := json.Unmarshal([]byte(input), &opts); err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if opts.UrlPattern != "" {
+			t.Errorf("UrlPattern = %q, want empty string", opts.UrlPattern)
+		}
+		if opts.UrlPrefix != "" {
+			t.Errorf("UrlPrefix = %q, want empty string", opts.UrlPrefix)
+		}
+	})
+
+	t.Run("singleton content type without url fields", func(t *testing.T) {
+		input := `{
+			"title": "Header",
+			"is_page": false,
+			"singleton": true,
+			"url_pattern": false,
+			"url_prefix": false
+		}`
+		var opts ContentTypeOptions
+		if err := json.Unmarshal([]byte(input), &opts); err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if !opts.Singleton {
+			t.Error("Singleton = false, want true")
+		}
+		if opts.UrlPattern != "" {
+			t.Errorf("UrlPattern = %q, want empty string", opts.UrlPattern)
+		}
+	})
+}