Return empty String if match fails in function

November 12, 2022

I have a function like this

fn get_html(address: &str) -> String {
    let mut response = reqwest::blocking::get(
        address,
    );

    response = response.unwrap_or_else(|_e| {String::from("")});
    response = response.text().unwrap_or_else(|_e| {String::from("")});
    return response
    }

Where I’m checking for html content. I would like to return an empty String if any kind of an error occurs somewhere in this function.
I’m not sure how to deal with this because unwrap_or_else expecting Result not String.

>Solution :

The reqwest::blocking::get() function is returning a Result<Response>.

To obtain the html, you have to unwrap this result and call .text() method.

That will return a Result<String>, that you have to unwrap again.

In your code you assign a String::from("") when you unwrap the Result<Response>, and that is not right, because you have a Response when it is Ok and a String when it is an Err.

Instead you should match the result and return the String from the function:

fn get_html(address: &str) -> String {
    let mut response = reqwest::blocking::get(
        address,
    );

    match response {
        Ok(response) => response.text().unwrap_or_else(|_e| String::from("")),
        Err(_) => String::from(""),
   }
}

In this code, you use unwrap_or_else() just on the .text() result.
While if you have an error on the response itself, you return a String from the function.