Adding "content-length" header to response causes closed connection. #862
Description
This is adapted from the streaming example from here
https://github.com/awslabs/aws-lambda-rust-runtime/blob/main/examples/basic-streaming-response/src/main.rs
use lambda_runtime::{
Error, LambdaEvent, service_fn,
streaming::{Body, Response},
tracing,
};
use serde_json::Value;
async fn func(_event: LambdaEvent<Value>) -> Result<Response<Body>, Error> {
let body = "hello\n";
let len = body.as_bytes().len();
let mut resp = Response::from(Body::from(body));
// resp.metadata_prelude.headers.append("content-type", "text/plain".parse().unwrap());
resp.metadata_prelude.headers.append("content-length", len.into());
Ok(resp)
}
#[tokio::main]
async fn main() -> Result<(), Error> {
// required to enable CloudWatch error logging by the runtime
tracing::init_default_subscriber();
lambda_runtime::run(service_fn(func)).await?;
Ok(())
}run it with cargo lambda watch, then curl -v
>curl -v http://127.0.0.1:9000
* Trying 127.0.0.1:9000...
* Connected to 127.0.0.1 (127.0.0.1) port 9000
> GET / HTTP/1.1
> Host: 127.0.0.1:9000
> User-Agent: curl/8.9.1
> Accept: */*
>
* Empty reply from server
* shutting down connection #0
curl: (52) Empty reply from server
remove the header will fix it, but I wonder why?
upload the binary on aws, it works just fine, except the header becomes "x-amzn-remapped-content-length", so I guess it's not lambda-runtime's fault.