How to: Http request

[Chandrian]

Hello, I've been trying to send https request from a lambda function and I'm having the hardest time ever. Please find below what I've tried, what is working and what is not working. Using Reqwest to make it easy. If you have any example to point me to or could explain what I'm doing wrong, it would be much appreciated, thank you!

What is working:
A simple get request and getting the body right away like below is working fine:

let body = reqwest::get(uri)
        .await?
        .text()
        .await?;
    info!("{}", body);

What is not working:

let client = reqwest::Client::new();
    let res = client.get(uri).send().await?;
    match res.status() {
        n @ StatusCode::OK => {info!("{}", res.text().await?);
            Ok::<String, Error>(format!("{}", n))},
        n => Ok::<String, Error>(format!("{}", n.as_str()))
    };

I'm getting the following error message:

let res = client.get(uri).send().await?;
    |         --- move occurs because `res` has type `reqwest::Response`, which does not implement the `Copy` trait
53  |     match res.status() {
54  |         n @ StatusCode::OK => {info!("{}", res.text().await?);
    |                                            ^^^ ------ `res` moved due to this method call
    |                                            |
    |                                            value used here after move
    |
note: this function takes ownership of the receiver `self`, which moves `res`
   --> response.rs:147:23
    |
147 |     pub async fn text(self) -> crate::Result<String> {
    |                       ^^^^

But the following compile on rust Playground:

use reqwest::{StatusCode, Client, Error};
use log::{info};

async fn foo() -> Result<String, Error>{
    let client = Client::new();
    let uri = "";
    let res = client.get(uri).send().await?;
    match res.status() {
        n @ StatusCode::OK => {info!("{}", res.text().await?);
            Ok::<String, Error>(format!("{}", n))},
        n => Ok::<String, Error>(format!("{}", n.as_str()))
    }
}

any idea?

[nmoutschen]

Hi @Chandrian!

There shouldn't be any difference whether or not you're running this code in a Lambda function. What version of Rust/Cargo are you currently using?

I'm thinking that you might be using an older version of Rust that cannot properly infer that reqwest::Response is safe to use since StatusCode implements Copy.

For reference, I wrote a small Lambda function using your code and I can compile it without any problem, using version 1.58.1:

use reqwest::{Client, StatusCode};
use lambda_runtime::{Context};

type Error = Box<dyn std::error::Error + Send + Sync>;

#[tokio::main]
async fn main() -> Result<(), Error> {
    lambda_runtime::run(lambda_runtime::handler_fn(my_handler)).await?;

    Ok(())
}

async fn my_handler(_value: serde_json::Value, _ctx: Context) -> Result<String, Error> {
    let client = Client::new();
    let uri = "";
    let res = client.get(uri).send().await?;
    match res.status() {
        n @ StatusCode::OK => {println!("{}", res.text().await?);
            Ok::<String, Error>(format!("{}", n))},
        n => Ok::<String, Error>(format!("{}", n.as_str()))
    }
}

[Chandrian]

Thank you @nmoutschen !

I thought I was up to date, but since it's working perfectly fine now, you must be right. Sorry :(. I guess it makes for a good example :)