use crate::io::BufMut;
use crate::postgres::protocol::Encode;
use byteorder::{BigEndian, ByteOrder, NetworkEndian};
pub struct StartupMessage<'a> {
pub params: &'a [(&'a str, &'a str)],
}
impl Encode for StartupMessage<'_> {
fn encode(&self, buf: &mut Vec<u8>) {
let pos = buf.len();
buf.put_i32::<NetworkEndian>(0);
buf.put_i32::<NetworkEndian>(196_608);
for (name, value) in self.params {
buf.put_str_nul(name);
buf.put_str_nul(value);
}
buf.push(0);
let len = buf.len() - pos;
BigEndian::write_i32(&mut buf[pos..], len as i32);
}
}
#[cfg(test)]
mod tests {
use super::{Encode, StartupMessage};
const STARTUP_MESSAGE: &[u8] = b"\0\0\0)\0\x03\0\0user\0postgres\0database\0postgres\0\0";
#[test]
fn it_encodes_startup_message() {
let mut buf = Vec::new();
let m = StartupMessage {
params: &[("user", "postgres"), ("database", "postgres")],
};
m.encode(&mut buf);
assert_eq!(buf, STARTUP_MESSAGE);
}
}