Function export_database

src/imex.rs:741–790

Exports the database to *dest*, encrypted using *passphrase*. The directory of *dest* must already exist, if *dest* itself exists it will be overwritten. This also verifies that IO is not running during the export.

(
    context: &Context,
    dest: &Path,
    passphrase: String,
    timestamp: i64,
)

///
/// This also verifies that IO is not running during the export.
async fn export_database(
    context: &Context,
    dest: &Path,
    passphrase: String,
    timestamp: i64,
) -> Result<()> {
    ensure!(
        !context.scheduler.is_running().await,
        "cannot export backup, IO is running"
    );
    let timestamp = timestamp.try_into().context("32-bit UNIX time overflow")?;

    // TODO: Maybe introduce camino crate for UTF-8 paths where we need them.
    let dest = dest
        .to_str()
        .with_context(|| format!("path {} is not valid unicode", dest.display()))?;

    context.set_config(Config::BccSelf, Some("1")).await?;
    context
        .sql
        .set_raw_config_int("backup_time", timestamp)
        .await?;
    context
        .sql
        .set_raw_config_int("backup_version", DCBACKUP_VERSION)
        .await?;
    sql::housekeeping(context).await.log_err(context).ok();
    context
        .sql
        .call_write(|conn| {
            conn.execute("VACUUM;", ())
                .map_err(|err| warn!(context, "Vacuum failed, exporting anyway {err}"))
                .ok();
            conn.execute("ATTACH DATABASE ? AS backup KEY ?", (dest, passphrase))
                .context("failed to attach backup database")?;
            let res = conn
                .query_row("SELECT sqlcipher_export('backup')", [], |_row| Ok(()))
                .context("failed to export to attached backup database");
            conn.execute(
                "UPDATE backup.config SET value='0' WHERE keyname='verified_one_on_one_chats';",
                [],
            )
            .ok(); // Deprecated 2025-07. If verified_one_on_one_chats was not set, this errors, which we ignore
            conn.execute("DETACH DATABASE backup", [])
                .context("failed to detach backup database")?;
            res?;
            Ok(())
        })
        .await
}

async fn check_backup_version(context: &Context) -> Result<()> {
    let version = (context.sql.get_raw_config_int("backup_version").await?).unwrap_or(2);