From e8e641786cb53b2060b263b3f754f413eac36c82 Mon Sep 17 00:00:00 2001
From: Alexander Weiss <alex@weissfam.de>
Date: Tue, 1 Mar 2022 12:45:02 +0100
Subject: [PATCH] better ser/de rules

---
 src/backend/node.rs | 32 ++++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/src/backend/node.rs b/src/backend/node.rs
index edc9523..9089864 100644
--- a/src/backend/node.rs
+++ b/src/backend/node.rs
@@ -15,8 +15,13 @@ pub struct Node {
     name: String,
     #[serde(flatten)]
     node_type: NodeType,
-    #[serde(deserialize_with = "deserialize_default_from_null")]
+    #[serde(
+        default,
+        deserialize_with = "deserialize_default_from_null",
+        skip_serializing_if = "Vec::is_empty"
+    )]
     content: Vec<Id>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     subtree: Option<Id>,
     #[serde(flatten)]
     meta: Metadata,
@@ -33,29 +38,36 @@ pub enum NodeType {
 
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize, Constructor, Getters)]
 pub struct Metadata {
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     size: u64,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     mtime: Option<DateTime<Local>>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     atime: Option<DateTime<Local>>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     ctime: Option<DateTime<Local>>,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     mode: u32,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     uid: u32,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     gid: u32,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     user: String,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     group: String,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     inode: u64,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     device_id: u64,
-    #[serde(default)]
+    #[serde(default, skip_serializing_if = "is_default")]
     links: u64,
 }
 
+fn is_default<T: Default + PartialEq>(t: &T) -> bool {
+    t == &T::default()
+}
+
 impl Node {
     pub fn new_file(name: OsString, meta: Metadata) -> Self {
         Self {