Fix to ensure required empty JSON arrays are unmarshaled as empty slices

generator/src/main/resources/line-bot-sdk-go-generator/model/struct.pebble

@@ -1,133 +1,135 @@
-{# @pebvariable name="model" type="org.openapitools.codegen.CodegenModel" -#}
-{# @pebvariable name="generatorClass" type="java.lang.String" -#}
-import (
-    "encoding/json"
-    "fmt"
-)
-
-// {{ model.classname }}
-// {{ model.description | escape }}{% if model.description == "" or model.description == null %}{{model.classname}}{% endif %}{% if model.isDeprecated %}
-// @deprecated{% endif %}
-{% if model.externalDocumentation != null -%}
-// {{  model.externalDocumentation.url() }}{% endif %}
-type {{model.classname}} struct {
-{% if model.parentModel != null %}
-    {{ model.parentModel.name }}
-{% endif %}
-{% for var in model.allVars -%}
-    {% if not(model.parentModel != null and model.parentModel.discriminator.propertyName==var.name) %}
-
-    /**
-        {% if var.description -%}
-     * {{ var.description | escape }}{% if var.required %} (Required){% endif %}
-        {% endif -%}
-        {% if not var.description -%}
-     * Get {{ var.name | escape }}
-        {% endif -%}
-        {% if var.minimum -%}
-     * minimum: {{var.minimum}}
-        {% endif -%}
-        {% if var.maximum -%}
-     * maximum: {{var.maximum}}
-        {% endif -%}
-        {% if var.deprecated -%}
-     * @deprecated
-    {% endif -%}
-    {% if var.externalDocs -%}
-     * {{var.externalDocs.description}}
-     * @see <a href="{{var.externalDocs.url}}">{{ var.externalDocs.summary | escape }} Documentation</a>
-    {% endif -%}
-     */
-    {{ var.name }} {{ var.vendorExtensions.get("x-type") }} `json:"{{var.baseName}}{% if isOmitEmpty(var) %},omitempty{% endif %}"`
-    {% endif %}
-{% endfor %}
-}
-
-{% if model.vendorExtensions["x-has-discriminator"] %}
-func (cr *{{model.classname}}) UnmarshalJSON(data []byte) error {
-	var raw map[string]json.RawMessage
-	err := json.Unmarshal(data, &raw)
-	if err != nil {
-		return fmt.Errorf("JSON parse error in map: %w", err)
-	}
-
-    {% for var in model.allVars %}
-    if raw["{{var.baseName}}"] != nil {
-        {% if var.vendorExtensions["x-is-discriminator"] %}
-        if raw{{ var.baseName }}, ok := raw["{{ var.baseName }}"]; ok && raw{{ var.baseName }} != nil {
-            {{ var.name }}, err := Unmarshal{{ var.baseType }}(raw{{ var.baseName }})
-            if err != nil {
-                return fmt.Errorf("JSON parse error in {{var.baseType}}(discriminator): %w", err)
-            }
-            cr.{{ var.name | capitalize }} = {{ var.name }}
-        }
-        {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
-        var raw{{ var.baseName }} []json.RawMessage
-        err = json.Unmarshal(raw["{{ var.baseName }}"], &raw{{ var.baseName }})
-        if err != nil {
-            return fmt.Errorf("JSON parse error in {{var.baseName}}({{var.baseType}}): %w", err)
-        }
-
-        for _, data := range raw{{ var.baseName }} {
-            e, err := Unmarshal{{ var.complexType }}(data)
-            if err != nil {
-                return fmt.Errorf("JSON parse error in {{ var.complexType }}(discriminator array): %w", err)
-            }
-            cr.{{ var.name | capitalize }} = append(cr.{{ var.name | capitalize }}, e)
-        }
-        {% else %}
-        err = json.Unmarshal(raw["{{ var.baseName }}"], &cr.{{ var.name | capitalize }})
-        if err != nil {
-            return fmt.Errorf("JSON parse error in {{var.baseType}}({{var.name | capitalize}}): %w", err)
-        }
-        {% endif %}
-    }
-    {% endfor %}
-
-	return nil
-}
-{% endif %}
-
-{# Fill discriminator field #}
-{% if model.vendorExtensions["x-has-discriminator"] or model.vendorExtensions["x-has-child-model"] or model.parentModel != null %}
-// MarshalJSON customizes the JSON serialization of the {{ model.classname }} struct.
-func (r *{{model.classname}}) MarshalJSON() ([]byte, error) {
-    {% if model.vendorExtensions["x-has-discriminator"] or model.vendorExtensions["x-has-child-model"] %}
-        {% for var in model.allVars -%}
-            {% if var.vendorExtensions["x-is-discriminator"] %}
-    r.{{ var.name }} = setDiscriminatorProperty{{ var.complexType }}(r.{{ var.name }})
-            {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
-    new{{ var.name }} := make({{ var.datatypeWithEnum }}Interface, len(r.{{ var.name }}))
-	for i, v := range r.{{ var.name }} {
-	    new{{ var.name }}[i] = setDiscriminatorProperty{{ var.complexType }}(v)
-	}
-            {% endif %}
-	    {% endfor %}
-    {% endif %}
-
-	type Alias {{model.classname}}
-	return json.Marshal(&struct {
-		*Alias
-    {% for var in model.allVars -%}
-        {% if var.vendorExtensions["x-is-discriminator-array"] or (model.parentModel != null and model.parentModel.discriminator.propertyName==var.name) %}
-    {{ var.name }} {{ var.vendorExtensions.get("x-type") }} `json:"{{var.baseName}}{% if isOmitEmpty(var) %},omitempty{% endif %}"`
-        {% endif %}
-    {% endfor %}
-	}{
-		Alias:    (*Alias)(r),
-    {% for var in model.allVars -%}
-        {% if model.parentModel != null and model.parentModel.discriminator.propertyName==var.name %}
-        {{ var.name }}: {% for mm in model.parentModel.discriminator.mappedModels -%}{% if mm.modelName==model.classname %}"{{ mm.mappingName }}"{% endif %}{% endfor %},
-        {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
-        {{ var.name }}: new{{ var.name }},
-        {% endif %}
-	{% endfor %}
-	})
-}
-{% endif %}
-
-{% for var in model.vars -%}
-    {% if var.isEnum %}
-{% include "./innerEnum.pebble" with {"model":model, "var":var} %}
-    {% endif %}
-{% endfor %}
+{# @pebvariable name="model" type="org.openapitools.codegen.CodegenModel" -#}
+{# @pebvariable name="generatorClass" type="java.lang.String" -#}
+import (
+    "encoding/json"
+    "fmt"
+)
+
+// {{ model.classname }}
+// {{ model.description | escape }}{% if model.description == "" or model.description == null %}{{model.classname}}{% endif %}{% if model.isDeprecated %}
+// @deprecated{% endif %}
+{% if model.externalDocumentation != null -%}
+// {{  model.externalDocumentation.url() }}{% endif %}
+type {{model.classname}} struct {
+{% if model.parentModel != null %}
+    {{ model.parentModel.name }}
+{% endif %}
+{% for var in model.allVars -%}
+    {% if not(model.parentModel != null and model.parentModel.discriminator.propertyName==var.name) %}
+
+    /**
+        {% if var.description -%}
+     * {{ var.description | escape }}{% if var.required %} (Required){% endif %}
+        {% endif -%}
+        {% if not var.description -%}
+     * Get {{ var.name | escape }}
+        {% endif -%}
+        {% if var.minimum -%}
+     * minimum: {{var.minimum}}
+        {% endif -%}
+        {% if var.maximum -%}
+     * maximum: {{var.maximum}}
+        {% endif -%}
+        {% if var.deprecated -%}
+     * @deprecated
+    {% endif -%}
+    {% if var.externalDocs -%}
+     * {{var.externalDocs.description}}
+     * @see <a href="{{var.externalDocs.url}}">{{ var.externalDocs.summary | escape }} Documentation</a>
+    {% endif -%}
+     */
+    {{ var.name }} {{ var.vendorExtensions.get("x-type") }} `json:"{{var.baseName}}{% if isOmitEmpty(var) %},omitempty{% endif %}"`
+    {% endif %}
+{% endfor %}
+}
+
+{% if model.vendorExtensions["x-has-discriminator"] %}
+func (cr *{{model.classname}}) UnmarshalJSON(data []byte) error {
+	var raw map[string]json.RawMessage
+	err := json.Unmarshal(data, &raw)
+	if err != nil {
+		return fmt.Errorf("JSON parse error in map: %w", err)
+	}
+
+    {% for var in model.allVars %}
+    if raw["{{var.baseName}}"] != nil {
+        {% if var.vendorExtensions["x-is-discriminator"] %}
+        if raw{{ var.baseName }}, ok := raw["{{ var.baseName }}"]; ok && raw{{ var.baseName }} != nil {
+            {{ var.name }}, err := Unmarshal{{ var.baseType }}(raw{{ var.baseName }})
+            if err != nil {
+                return fmt.Errorf("JSON parse error in {{var.baseType}}(discriminator): %w", err)
+            }
+            cr.{{ var.name | capitalize }} = {{ var.name }}
+        }
+        {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
+        var raw{{ var.baseName }} []json.RawMessage
+        err = json.Unmarshal(raw["{{ var.baseName }}"], &raw{{ var.baseName }})
+        if err != nil {
+            return fmt.Errorf("JSON parse error in {{var.baseName}}({{var.baseType}}): %w", err)
+        }
+
+        {% if var.required %}cr.{{ var.name | capitalize }} = make({{ var.vendorExtensions.get("x-type") }}, 0, len(raw{{ var.baseName }})){% endif %}
+
+        for _, data := range raw{{ var.baseName }} {
+            e, err := Unmarshal{{ var.complexType }}(data)
+            if err != nil {
+                return fmt.Errorf("JSON parse error in {{ var.complexType }}(discriminator array): %w", err)
+            }
+            cr.{{ var.name | capitalize }} = append(cr.{{ var.name | capitalize }}, e)
+        }
+        {% else %}
+        err = json.Unmarshal(raw["{{ var.baseName }}"], &cr.{{ var.name | capitalize }})
+        if err != nil {
+            return fmt.Errorf("JSON parse error in {{var.baseType}}({{var.name | capitalize}}): %w", err)
+        }
+        {% endif %}
+    }
+    {% endfor %}
+
+	return nil
+}
+{% endif %}
+
+{# Fill discriminator field #}
+{% if model.vendorExtensions["x-has-discriminator"] or model.vendorExtensions["x-has-child-model"] or model.parentModel != null %}
+// MarshalJSON customizes the JSON serialization of the {{ model.classname }} struct.
+func (r *{{model.classname}}) MarshalJSON() ([]byte, error) {
+    {% if model.vendorExtensions["x-has-discriminator"] or model.vendorExtensions["x-has-child-model"] %}
+        {% for var in model.allVars -%}
+            {% if var.vendorExtensions["x-is-discriminator"] %}
+    r.{{ var.name }} = setDiscriminatorProperty{{ var.complexType }}(r.{{ var.name }})
+            {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
+    new{{ var.name }} := make({{ var.datatypeWithEnum }}Interface, len(r.{{ var.name }}))
+	for i, v := range r.{{ var.name }} {
+	    new{{ var.name }}[i] = setDiscriminatorProperty{{ var.complexType }}(v)
+	}
+            {% endif %}
+	    {% endfor %}
+    {% endif %}
+
+	type Alias {{model.classname}}
+	return json.Marshal(&struct {
+		*Alias
+    {% for var in model.allVars -%}
+        {% if var.vendorExtensions["x-is-discriminator-array"] or (model.parentModel != null and model.parentModel.discriminator.propertyName==var.name) %}
+    {{ var.name }} {{ var.vendorExtensions.get("x-type") }} `json:"{{var.baseName}}{% if isOmitEmpty(var) %},omitempty{% endif %}"`
+        {% endif %}
+    {% endfor %}
+	}{
+		Alias:    (*Alias)(r),
+    {% for var in model.allVars -%}
+        {% if model.parentModel != null and model.parentModel.discriminator.propertyName==var.name %}
+        {{ var.name }}: {% for mm in model.parentModel.discriminator.mappedModels -%}{% if mm.modelName==model.classname %}"{{ mm.mappingName }}"{% endif %}{% endfor %},
+        {% elseif var.vendorExtensions["x-is-discriminator-array"] %}
+        {{ var.name }}: new{{ var.name }},
+        {% endif %}
+	{% endfor %}
+	})
+}
+{% endif %}
+
+{% for var in model.vars -%}
+    {% if var.isEnum %}
+{% include "./innerEnum.pebble" with {"model":model, "var":var} %}
+    {% endif %}
+{% endfor %}

go.mod

@@ -1,3 +1,3 @@
 module github.com/line/line-bot-sdk-go/v8
 
-go 1.24
+go 1.24.4

line-openapi

@@ -0,0 +1 @@
+../line-openapi/

linebot/messaging_api/model_broadcast_request.go

@@ -55,6 +55,8 @@ func (cr *BroadcastRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_buttons_template.go

@@ -161,6 +161,8 @@ func (cr *ButtonsTemplate) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in actions(array): %w", err)
 		}
 
+		cr.Actions = make([]ActionInterface, 0, len(rawactions))
+
 		for _, data := range rawactions {
 			e, err := UnmarshalAction(data)
 			if err != nil {

linebot/messaging_api/model_carousel_column.go

@@ -123,6 +123,8 @@ func (cr *CarouselColumn) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in actions(array): %w", err)
 		}
 
+		cr.Actions = make([]ActionInterface, 0, len(rawactions))
+
 		for _, data := range rawactions {
 			e, err := UnmarshalAction(data)
 			if err != nil {

linebot/messaging_api/model_confirm_template.go

@@ -74,6 +74,8 @@ func (cr *ConfirmTemplate) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in actions(array): %w", err)
 		}
 
+		cr.Actions = make([]ActionInterface, 0, len(rawactions))
+
 		for _, data := range rawactions {
 			e, err := UnmarshalAction(data)
 			if err != nil {

linebot/messaging_api/model_flex_box.go

@@ -208,6 +208,8 @@ func (cr *FlexBox) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in contents(array): %w", err)
 		}
 
+		cr.Contents = make([]FlexComponentInterface, 0, len(rawcontents))
+
 		for _, data := range rawcontents {
 			e, err := UnmarshalFlexComponent(data)
 			if err != nil {

linebot/messaging_api/model_imagemap_message.go

@@ -135,6 +135,8 @@ func (cr *ImagemapMessage) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in actions(array): %w", err)
 		}
 
+		cr.Actions = make([]ImagemapActionInterface, 0, len(rawactions))
+
 		for _, data := range rawactions {
 			e, err := UnmarshalImagemapAction(data)
 			if err != nil {

linebot/messaging_api/model_multicast_request.go

@@ -65,6 +65,8 @@ func (cr *MulticastRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_narrowcast_request.go

@@ -70,6 +70,8 @@ func (cr *NarrowcastRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_pnp_messages_request.go

@@ -60,6 +60,8 @@ func (cr *PnpMessagesRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_push_message_request.go

@@ -74,6 +74,8 @@ func (cr *PushMessageRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_reply_message_request.go

@@ -69,6 +69,8 @@ func (cr *ReplyMessageRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {

linebot/messaging_api/model_rich_menu_batch_request.go

@@ -55,6 +55,8 @@ func (cr *RichMenuBatchRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in operations(array): %w", err)
 		}
 
+		cr.Operations = make([]RichMenuBatchOperationInterface, 0, len(rawoperations))
+
 		for _, data := range rawoperations {
 			e, err := UnmarshalRichMenuBatchOperation(data)
 			if err != nil {

linebot/messaging_api/model_validate_message_request.go

@@ -50,6 +50,8 @@ func (cr *ValidateMessageRequest) UnmarshalJSON(data []byte) error {
 			return fmt.Errorf("JSON parse error in messages(array): %w", err)
 		}
 
+		cr.Messages = make([]MessageInterface, 0, len(rawmessages))
+
 		for _, data := range rawmessages {
 			e, err := UnmarshalMessage(data)
 			if err != nil {