Switch from base64 to data-encoding

It offers the same functionality with a simpler API and lower MSRV.

Cargo.toml

@@ -80,7 +80,7 @@ __rustls = ["hyper-rustls", "tokio-rustls", "rustls", "__tls", "rustls-pemfile"]
 __internal_proxy_sys_no_cache = []
 
 [dependencies]
-base64 = "0.21"
+data-encoding = "2.4"
 http = "0.2"
 url = "2.2"
 bytes = "1.0"

src/util.rs

@@ -5,19 +5,18 @@ where
     U: std::fmt::Display,
     P: std::fmt::Display,
 {
-    use base64::prelude::BASE64_STANDARD;
-    use base64::write::EncoderWriter;
-    use std::io::Write;
+    use data_encoding::BASE64;
 
-    let mut buf = b"Basic ".to_vec();
-    {
-        let mut encoder = EncoderWriter::new(&mut buf, &BASE64_STANDARD);
-        let _ = write!(encoder, "{}:", username);
-        if let Some(password) = password {
-            let _ = write!(encoder, "{}", password);
-        }
+    let mut buf = String::from("Basic ");
+    let mut input = username.to_string();
+    input.push(':');
+    if let Some(password) = password {
+        input.push_str(&password.to_string());
     }
-    let mut header = HeaderValue::from_bytes(&buf).expect("base64 is always valid HeaderValue");
+    BASE64.encode_append(input.as_bytes(), &mut buf);
+
+    let mut header =
+        HeaderValue::from_bytes(buf.as_bytes()).expect("base64 is always valid HeaderValue");
     header.set_sensitive(true);
     header
 }