Use PathBuf type to clarify usage of paths

src/config.rs

@@ -26,14 +26,15 @@
 //! ```
 
 use std::collections::HashMap;
+use std::path::PathBuf;
 
 use serde::{Deserialize, Serialize};
 
 /// Paths to the client certificate and client key PEM files
 #[derive(Serialize, Deserialize, Debug)]
 pub struct EppClientTlsFiles {
-    pub cert_chain: String,
-    pub key: String,
+    pub cert_chain: PathBuf,
+    pub key: PathBuf,
 }
 
 /// Config that stores settings for multiple registries

src/connection.rs

@@ -158,7 +158,7 @@ async fn epp_connect(
             let mut r = BufReader::new(File::open(key_file).unwrap());
             let mut rsa_keys = rustls_pemfile::rsa_private_keys(&mut r).unwrap();
             if rsa_keys.len() > 1 {
-                warn!("Multiple RSA keys found in PEM file {}", key_file);
+                warn!("Multiple RSA keys found in PEM file {:?}", key_file);
             }
             key = rsa_keys.pop();
 
@@ -166,7 +166,7 @@ async fn epp_connect(
                 r.seek(SeekFrom::Start(0))?;
                 let mut pkcs8_keys = rustls_pemfile::pkcs8_private_keys(&mut r).unwrap();
                 if pkcs8_keys.len() > 1 {
-                    warn!("Multiple PKCS8 keys found in PEM file {}", key_file);
+                    warn!("Multiple PKCS8 keys found in PEM file {:?}", key_file);
                 }
                 key = pkcs8_keys.pop();
             }