max / goingson

backup: serialize exports directly to the writer Avoid holding the full serialized JSON in memory alongside the already-in-memory export. write_backup streams into the gzip encoder via serde_json::to_writer; write_json streams into a buffered file writer via to_writer_pretty. Removes the second full-dataset copy on both export paths. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: Max Johnson <me@maxj.phd> · 2026-07-11 00:52 UTC

Commit: 64b973bc5fdeb0f6303b8cd712cd4c8193e5b413

Parent: 2ff4ea7

1 file changed, +9 insertions, -5 deletions

M src-tauri/src/export/backup.rs +9 -5

			@@ -3,7 +3,7 @@
3	3		//! Provides compressed JSON backup creation and restoration for all GoingsOn data.
4	4
5	5		use std::fs::File;
6		-	use std::io::{Read, Write};
	6	+	use std::io::{BufWriter, Read, Write};
7	7		use std::path::Path;
8	8
9	9		use chrono::{DateTime, Utc};
			@@ -159,8 +159,9 @@ pub fn write_backup<P: AsRef<Path>>(export: &FullExport, path: P) -> Result<u64,
159	159		let file = File::create(&tmp_path)?;
160	160		let mut encoder = GzEncoder::new(file, Compression::default());
161	161
162		-	let json = serde_json::to_vec(export)?;
163		-	encoder.write_all(&json)?;
	162	+	// Serialize straight into the compressor so we never hold the full
	163	+	// serialized JSON in memory alongside the already-in-memory export.
	164	+	serde_json::to_writer(&mut encoder, export)?;
164	165		encoder.finish()?;
165	166
166	167		// Prevents corrupt backups if the process crashes mid-write
			@@ -211,10 +212,13 @@ pub fn read_backup<P: AsRef<Path>>(path: P) -> Result<FullExport, BackupError> {
211	212		///
212	213		/// The size of the file in bytes.
213	214		pub fn write_json<P: AsRef<Path>>(export: &FullExport, path: P) -> Result<u64, BackupError> {
214		-	let json = serde_json::to_string_pretty(export)?;
215	215		let dest = path.as_ref();
216	216		let tmp = dest.with_extension("json.tmp");
217		-	std::fs::write(&tmp, &json)?;
	217	+	// Stream the serialized JSON directly to the file through a buffered
	218	+	// writer instead of building the whole pretty-printed string in memory.
	219	+	let mut writer = BufWriter::new(File::create(&tmp)?);
	220	+	serde_json::to_writer_pretty(&mut writer, export)?;
	221	+	writer.flush()?;
218	222		std::fs::rename(&tmp, dest)?;
219	223
220	224		let metadata = std::fs::metadata(dest)?;