Improve error messages

Cargo.lock

@@ -159,6 +159,7 @@ dependencies = [
 name = "client"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
  "env_logger 0.8.1",
  "input",
  "log",
@@ -659,6 +660,7 @@ dependencies = [
 name = "server"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
  "env_logger 0.8.1",
  "input",
  "log",

client/Cargo.toml

@@ -16,3 +16,4 @@ structopt = "0.3.20"
 log = "0.4.11"
 env_logger = "0.8.1"
 tokio-native-tls = "0.2.0"
+anyhow = "1.0.33"

client/src/main.rs

@@ -1,10 +1,10 @@
 mod config;
 
+use anyhow::{Context, Error};
 use config::Config;
 use input::EventWriter;
 use net::{self, Message, PROTOCOL_VERSION};
 use std::convert::Infallible;
-use std::io::{Error, ErrorKind};
 use std::path::{Path, PathBuf};
 use std::process;
 use structopt::StructOpt;
@@ -13,22 +13,24 @@ use tokio::net::TcpStream;
 use tokio_native_tls::native_tls::{Certificate, TlsConnector};
 
 async fn run(server: &str, port: u16, certificate_path: &Path) -> Result<Infallible, Error> {
-    let certificate = fs::read(certificate_path).await?;
+    let certificate = fs::read(certificate_path)
+        .await
+        .context("Failed to read certificate")?;
     let certificate = Certificate::from_der(&certificate)
         .or_else(|_| Certificate::from_pem(&certificate))
-        .map_err(|err| Error::new(ErrorKind::InvalidData, err))?;
+        .context("Failed to parse certificate")?;
 
     let connector: tokio_native_tls::TlsConnector = TlsConnector::builder()
         .add_root_certificate(certificate)
         .build()
-        .map_err(|err| Error::new(ErrorKind::InvalidData, err))
+        .context("Failed to create connector")?
-        .map(Into::into)?;
+        .into();
 
     let stream = TcpStream::connect((server, port)).await?;
     let mut stream = connector
         .connect(server, stream)
         .await
-        .map_err(|err| Error::new(ErrorKind::InvalidData, err))?;
+        .context("Failed to connect")?;
 
     log::info!("Connected to {}:{}", server, port);
 
@@ -36,12 +38,10 @@ async fn run(server: &str, port: u16, certificate_path: &Path) -> Result<Infalli
 
     let version = net::read_version(&mut stream).await?;
     if version != PROTOCOL_VERSION {
-        return Err(Error::new(
+        return Err(anyhow::anyhow!(
-            ErrorKind::InvalidData,
+            "Incompatible protocol version (got {}, expecting {})",
-            format!(
+            version,
-                "Incompatible protocol version (got {}, expecting {})",
+            PROTOCOL_VERSION
-                version, PROTOCOL_VERSION
-            ),
         ));
     }
 
@@ -89,7 +89,7 @@ async fn main() {
     tokio::select! {
         result = run(&config.server.hostname, config.server.port, &config.certificate_path) => {
             if let Err(err) = result {
-                log::error!("Error: {}", err);
+                log::error!("Error: {:#}", err);
                 process::exit(1);
             }
         }

server/Cargo.toml

@@ -16,3 +16,4 @@ structopt = "0.3.20"
 log = "0.4.11"
 env_logger = "0.8.1"
 tokio-native-tls = "0.2.0"
+anyhow = "1.0.33"

server/src/main.rs

@@ -1,11 +1,11 @@
 mod config;
 
+use anyhow::{Context, Error};
 use config::Config;
 use input::{Direction, Event, EventManager};
 use net::{self, Message, PROTOCOL_VERSION};
 use std::collections::{HashMap, HashSet};
 use std::convert::Infallible;
-use std::io::{Error, ErrorKind};
 use std::net::SocketAddr;
 use std::path::{Path, PathBuf};
 use std::process;
@@ -29,12 +29,10 @@ where
 
     let version = net::read_version(&mut stream).await?;
     if version != PROTOCOL_VERSION {
-        return Err(Error::new(
+        return Err(anyhow::anyhow!(
-            ErrorKind::InvalidData,
+            "Incompatible protocol version (got {}, expecting {})",
-            format!(
+            version,
-                "Incompatible protocol version (got {}, expecting {})",
+            PROTOCOL_VERSION
-                version, PROTOCOL_VERSION
-            ),
         ));
     }
 
@@ -55,11 +53,13 @@ async fn run(
     identity_path: &Path,
     identity_password: &str,
 ) -> Result<Infallible, Error> {
-    let identity = fs::read(identity_path).await?;
+    let identity = fs::read(identity_path)
-    let identity = Identity::from_pkcs12(&identity, identity_password)
+        .await
-        .map_err(|err| Error::new(ErrorKind::InvalidData, err))?;
+        .context("Failed to read identity")?;
+    let identity =
+        Identity::from_pkcs12(&identity, identity_password).context("Failed to parse identity")?;
     let acceptor: tokio_native_tls::TlsAcceptor = TlsAcceptor::new(identity)
-        .map_err(|err| Error::new(ErrorKind::InvalidData, err))
+        .context("Failed to create TLS acceptor")
         .map(Into::into)?;
     let listener = TcpListener::bind(listen_address).await?;
 
@@ -185,7 +185,7 @@ async fn main() {
     tokio::select! {
         result = run(config.listen_address, &config.switch_keys, &config.identity_path, &config.identity_password) => {
             if let Err(err) = result {
-                log::error!("Error: {}", err);
+                log::error!("Error: {:#}", err);
                 process::exit(1);
             }
         }