t8y2/dbx · error

Failed to migrate JSON data

Error message

Failed to migrate JSON data

What it means

After opening storage, the app runs s.migrate_from_json(&data_dir) to import legacy JSON files into the new database and panics if migration fails. Failures stem from malformed or unreadable legacy JSON files or database write errors during import.

Source

Thrown at src-tauri/src/lib.rs:1514

            let data_dir = data_dir_resolution.data_dir.clone();
            std::fs::create_dir_all(&data_dir).expect("Failed to create data dir");
            let data_dir_mode = startup_data_dir_mode(&data_dir_resolution.mode);
            append_startup_probe(format!("data dir ready mode={data_dir_mode}"));
            let alternative_data_dir = data_dir::alternative_data_dir(&data_dir_resolution);
            match maybe_import_user_data_db(&data_dir, alternative_data_dir.as_deref()) {
                Ok(result) => eprintln!("[STARTUP] data db fallback import: {result:?}"),
                Err(err) => eprintln!("[STARTUP] data db fallback import failed: {err}"),
            }
            let db_path = data_dir.join("dbx.db");

            let t = Instant::now();
            append_startup_probe(format!("opening storage file=dbx.db data_dir_mode={data_dir_mode}"));
            let storage = tauri::async_runtime::block_on(async {
                let s = Storage::open(&db_path).await.expect("Failed to open storage");
                eprintln!("[STARTUP]   Storage::open in {:?}", t.elapsed());
                append_startup_probe(format!("storage opened in {:?}", t.elapsed()));
                let t2 = Instant::now();
                s.migrate_from_json(&data_dir).await.expect("Failed to migrate JSON data");
                eprintln!("[STARTUP]   migrate_from_json in {:?}", t2.elapsed());
                append_startup_probe(format!("json migration completed in {:?}", t2.elapsed()));
                s
            });
            let desktop_settings = tauri::async_runtime::block_on(storage.load_desktop_settings()).unwrap_or_default();
            app.handle().plugin(
                tauri_plugin_log::Builder::default()
                    .timezone_strategy(tauri_plugin_log::TimezoneStrategy::UseLocal)
                    .format(|out, message, record| {
                        out.finish(format_args!(
                            "[{}][{}][{}] {}",
                            chrono::Local::now().format("%Y-%m-%d][%H:%M:%S%.3f"),
                            record.level(),
                            record.target(),
                            message
                        ));
                    })
                    .level(log::LevelFilter::Debug)

View on GitHub (pinned to c0390bff16)

Solutions

1. Back up and move the offending JSON files out of the data dir so the app can start with an empty database.
2. Inspect the legacy JSON files with a validator to find malformed entries and fix or remove them.
3. Downgrade to the previous app version to export clean data, or handle the Result with a skip-and-log policy for bad records instead of expect().

Example fix

// before
s.migrate_from_json(&data_dir).await.expect("Failed to migrate JSON data");
// after
if let Err(e) = s.migrate_from_json(&data_dir).await {
    eprintln!("[STARTUP] JSON migration failed (continuing with empty db): {e}");
}

// Rust: validate legacy JSON before migrating
fn json_files_parse(dir: &std::path::Path) -> Vec<std::path::PathBuf> {
    std::fs::read_dir(dir).into_iter().flatten()
        .filter_map(|e| e.ok().map(|e| e.path()))
        .filter(|p| p.extension().map_or(false, |x| x == "json"))
        .filter(|p| std::fs::read_to_string(p)
            .map(|s| serde_json::from_str::<serde_json::Value>(&s).is_err())
            .unwrap_or(true))
        .collect()
}

match s.migrate_from_json(&data_dir).await {
    Ok(()) => {}
    Err(e) => eprintln!("[STARTUP] JSON migration failed, continuing: {e}"),
}

When it happens

Trigger: migrate_from_json at lib.rs:1514 failing when legacy JSON files in the data dir are corrupt, have unsupported schema versions, or the newly opened storage rejects writes (permissions, constraints, disk full).

Common situations: Users upgrading from the JSON-based version with hand-edited or partially synced JSON files; interrupted previous migration leaving partial state; JSON encoding incompatibilities after a version change.

Related errors

• Failed to migrate JSON data
• TDengine database is required
• {key} is required
• Failed to open storage
• invalid_json

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/e40fa4036f167adc. Report an issue: GitHub.