Response bytes

[josejachuf]

Hi,

How to do a Response as type bytes?
I want server vector tiles [1] from postgres/postgis
The Content-Type is application/octet-stream

the query is similar to this (python):

cur = conn.cursor()
query = """
    SELECT
        ST_AsMVT(tile)
    FROM
        (SELECT
            id,
            name,
            ST_AsMVTGeom(ST_SimplifyPreserveTopology(geom, 0.1),
                ST_Makebox2d(ST_MakePoint(%s, %s),
                             ST_MakePoint(%s, %s)
                             ), 4096, 0, false) AS geom
        FROM my_layer) AS tile
"""

cur.execute(query, (xmin, ymin, xmax, ymax))
tile = bytes(cur.fetchone()[0])
response.headers['Content-Type'] = "application/octet-stream"
return tile

Thanks
Jose

[1] https://en.wikipedia.org/wiki/Vector_tiles

[chrislearn]

#[handler]
async fn example(res: &mut Response) {
    res.header_mut().insert("content-type".parse().unwrap(), "application/octet-stream".parse().unwrap());
    res.set_body(Body::Once(Bytes::from(b"hello")));
}

https://docs.rs/salvo_core/latest/salvo_core/http/response/struct.Response.html#method.set_body
https://docs.rs/bytes/1.2.1/bytes/struct.Bytes.html

[josejachuf]

Thank you @chrislearn

I add:

use salvo::http::response::Body;
use bytes::Bytes;

but I get this error

res.set_body(Body::Once(Bytes::from(b"hello")));
                        ^^^^^^^^^^^ the trait `From<&[u8; 5]>` is not implemented for `bytes::Bytes`

I'm sorry, I'm very rookie

[chrislearn]

try

Bytes::from(&b"hello world"[..]);

[josejachuf]

This works fine. Then I will ask, when I try, the part of return the vector tile specifically

use salvo::prelude::*;
use salvo::http::{response::Body, header};
use bytes::Bytes;

#[handler]
async fn hello_world() -> &'static str {
    "Hello World"
}

#[handler]
async fn hello_world4(res: &mut Response) {
    res.headers_mut().insert(header::CONTENT_TYPE, "application/octet-stream".parse().unwrap());
    // res.set_body(Body::Once(Bytes::from("hello")));
    res.set_body(Body::Once(Bytes::from(&b"hello"[..])));
}


#[tokio::main]
async fn main() {
    tracing_subscriber::fmt().init();

    tracing::info!("Listening on http://127.0.0.1:7878");
    Server::new(TcpListener::bind("127.0.0.1:7878")).serve(route()).await;
}

fn route() -> Router {
    Router::new()
        .get(hello_world)
        .push(Router::with_path("hello4").get(hello_world4))
}