You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: mod.rs
    path of file: ./repos/dim/dim-core/src/reactor
    
    the code of the file until where you have to start completion: pub mod handler;
mod types;

use async_trait::async_trait;

use libsqlite3_sys::sqlite3;
use rusqlite::hooks::Action;
use rusqlite::Connection;
use sqlx::SqliteConnection;

use std::os::raw::c_char;
use std::os::raw::c_int;
use std::os::raw::c_void;
use std::panic::catch_unwind;
use std::sync::Arc;
use std::sync::Mutex;
use std::time::Duration;
use std::time::Instant;

use tokio::sync::mpsc::unbounded_channel;
use tokio::sync::mpsc::UnboundedReceiver;
use tokio::sync::mpsc::UnboundedSe
    
    fn wal_hook(&self) -> impl FnMut() + Send + 'static {
        let context = self.hook_ctx.clone();

        // NOTE: If we get a commit we can assume our buffer of events is valid and can be reacted
        // on because they are going to be written to the disk.
        move || {
            let now = Instant::now();
            let mut buffer = context.uncommited_buffer.lock().unwrap();
            let buffer_len = buffer.len();

            while let Some(event) = buffer.pop() {
                if let Err(_) = context.tx.send(event) {
                    error!("Failed to send database event.");
                }
            }

            let elapsed = now.elapsed();
            if elapsed > MAX_COMMIT_DURATION {
                warn!(
                    elapsed_ms = elapsed.as_millis(),
                    buffer_len, "Commit hook took too long"
                );
            }
        }
    }