A wrapper crate of queue-file for bincode serializable structs.
use chrono::{DateTime, Utc};
use pq_bincode::{IBincodeSerializable, PQBincode};
use serde::{Deserialize, Serialize};
use std::io::{Result as IOResult, Write};
#[derive(Clone, Debug, Deserialize, Serialize, Ord, PartialOrd, Eq, PartialEq)]
pub struct Person {
pub name: String,
pub birthdate: DateTime<Utc>,
}
impl Default for Person {
fn default() -> Person {
Person {
name: "John Doe".into(),
birthdate: Utc::now(),
}
}
}
impl IBincodeSerializable for Person {}
fn pq_test(pq: &mut PQBincode<Person>) -> IOResult<()> {
println!("PQ path is \"{}\"", pq.get_persistent_path());
println!("Current PQ count is {}", pq.count()); // 0 count
print!("Inserting two identical John Doe...");
std::io::stdout().flush()?;
let john_doe = Person::default();
pq.enqueue(john_doe.clone())?;
pq.enqueue(john_doe)?;
println!("DONE");
println!("Current PQ count is {}", pq.count()); // 2 count
print!("Trying cancellable dequeue (Cancel)...");
std::io::stdout().flush()?;
pq.cancellable_dequeue(|_| false)?;
println!("DONE");
println!("Current PQ count is {}", pq.count()); // 2 count
print!("Trying cancellable dequeue (Proceed)...");
std::io::stdout().flush()?;
pq.cancellable_dequeue(|_| true)?;
println!("DONE");
println!("Current PQ count is {}", pq.count()); // 1 count
print!("Trying a simple dequeue...");
std::io::stdout().flush()?;
let dequeued_item = pq.dequeue()?;
println!("DONE");
println!("Current PQ count is {}", pq.count()); // 0 count
println!("Dequeued item:\n{:#?}", dequeued_item);
Ok(())
}
fn main() -> IOResult<()> {
let mut pq_person = PQBincode::<Person>::new("person.pqb")?;
pq_test(&mut pq_person)?;
Ok(())
}Or, just run cargo run --example allfeatures it will yield:
PQ path is "person.pqb"
Current PQ count is 0
Inserting two identical John Doe...DONE
Current PQ count is 2
Trying cancellable dequeue (Cancel)...DONE
Current PQ count is 2
Trying cancellable dequeue (Proceed)...DONE
Current PQ count is 1
Trying a simple dequeue...DONE
Current PQ count is 0
Dequeued item:
Some(
Person {
name: "John Doe",
birthdate: 2020-09-11T09:48:32.470091527Z,
},
)