From 6c8d15f4b2c0bacf5cb9fe5ad527ce219b97e0e9 Mon Sep 17 00:00:00 2001
From: Scott Worley <scottworley@scottworley.com>
Date: Tue, 10 Oct 2023 18:16:08 -0700
Subject: [PATCH] server: Hand-implement Serialize

Mostly for symmetry with Deserialize, for which the lack of #[serde(flatten)]
support hurts much wors.
---
 server/Cargo.toml  |  2 +-
 server/src/main.rs | 21 +++++++++++++++++----
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/server/Cargo.toml b/server/Cargo.toml
index 9fbdf1f..01a4b3f 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -12,4 +12,4 @@ version = "0.0.1"
 
 [dependencies]
 csv = "1.3.0"
-serde = { version = "1.0", features = ["derive"] }
+serde = "1.0"
diff --git a/server/src/main.rs b/server/src/main.rs
index 96f35b2..500c2f5 100644
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-use serde::Serialize;
+use serde::ser::{Serialize, SerializeStruct, Serializer};
 use std::collections::HashMap;
 use std::net::UdpSocket;
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
@@ -22,7 +22,7 @@ use std::time::{Duration, SystemTime, UNIX_EPOCH};
 const MESSAGE_SIZE: usize = 12;
 const LOGFILENAME: &str = "log.csv";
 
-#[derive(Eq, Debug, Hash, PartialEq, Serialize)]
+#[derive(Eq, Debug, Hash, PartialEq)]
 struct MessageKey {
     epoch: u32,
     device: u16,
@@ -34,6 +34,20 @@ struct Message {
     key: MessageKey,
     t: u64,
 }
+impl Serialize for Message {
+    // https://github.com/BurntSushi/rust-csv/issues/155
+    // https://github.com/BurntSushi/rust-csv/issues/98
+    // https://github.com/BurntSushi/rust-csv/pull/223
+    // csv doesn't support #[serde(flatten)], so we implement this directly.  :(
+    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        let mut row = serializer.serialize_struct("Message", 4)?;
+        row.serialize_field("epoch", &self.key.epoch)?;
+        row.serialize_field("device", &self.key.device)?;
+        row.serialize_field("seq", &self.key.seq)?;
+        row.serialize_field("t", &self.t)?;
+        row.end()
+    }
+}
 
 impl From<&[u8; MESSAGE_SIZE]> for Message {
     fn from(value: &[u8; MESSAGE_SIZE]) -> Self {
@@ -121,8 +135,7 @@ fn main() {
                     continue;
                 }
                 let message = Message::try_from(filled_buf).expect("I can't count");
-                log.serialize((&message.key, message.t))
-                    .expect("Couldn't write log");
+                log.serialize(&message).expect("Couldn't write log");
                 log.flush().expect("Couldn't flush log");
                 merge_message(&mut presses, message);
             }
-- 
2.44.1