0

I'm trying to use reqwest library to download a PNG file, but when I download it I see a strange behaviour respect other programming languages like: Python.

For instance:

let content = reqwest::get("https://www.google.es/images/searchbox/desktop_searchbox_sprites302_hr.png").await?;

If I print the result as a bytes array (println!("{:?}", content.text().await?.as_bytes());

[ 191, 189, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82, 0, 0, 0, 40, 0, 0, 0, 82, 8, 3, 0, 0, 0, 17,  191, 189, 102,  191, 189, 0, 0, 0, 108, 80, 76, 84, 69, 0, 0, 0,  191, 189,  191, 189,  191, 189,...]

However, the result using Python requests is:

[137, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82, 0, 0, 0, 40, 0, 0, 0, 82, 8, 3, 0, 0, 0, 17, 153, 102, 248, ...]

In the Rust version, I see a lot of 191, 189. This sequence repeats a lot throughout the array, but in Python doesn't appear at all.

What am I doing wrong in Rust?

Shepmaster
  • 388,571
  • 95
  • 1,107
  • 1,366
ALX
  • 19
  • 1
    It's hard to answer your question because it doesn't include a [MRE]. We can't tell what crates (and their versions), types, traits, fields, etc. are present in the code. It would make it easier for us to help you if you try to reproduce your error on the [Rust Playground](https://play.rust-lang.org) if possible, otherwise in a brand new Cargo project, then [edit] your question to include the additional info. There are [Rust-specific MRE tips](//stackoverflow.com/tags/rust/info) you can use to reduce your original code for posting here. Thanks! – Shepmaster Sep 01 '20 at 20:12

1 Answers1

3

I see a lot of 191, 189

It's better seen as EF, BF, BD, which is the Unicode replacement character encoded as UTF-8. Binary data is not text data. You should not use text for binary data, instead use bytes.

const URL: &str = "https://www.google.es/images/searchbox/desktop_searchbox_sprites302_hr.png";

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let content = reqwest::get(URL).await?;
    let bytes = content.bytes().await?;
    println!("{:x?}", &bytes[..]);

    Ok(())
}

[89, 50, 4e, 47, d, a, 1a, a, 0, 0, 0, d, 49, 48, 44, 52, 0, 0, 0, 28, 0, 0, 0, 52, 8, 3, 0, 0, 0, 11, 99, 66, f8, 0, 0, 0, 6c, 50, 4c, 54, 45, 0, 0, 0, 9f, ...
Shepmaster
  • 388,571
  • 95
  • 1,107
  • 1,366
  • Thank you very much for your help. This answer has helped me to solve this issue. I didn't see the method bytes() when I checked out reqwest documentation ;) – ALX Sep 02 '20 at 00:03