feat: thiserror, tracingクレートの導入 (#8)

clocking-server/Cargo.toml

@@ -7,5 +7,10 @@ edition = "2021"
 clap = { version = "4.5.15", features = ["derive", "env"] }
 dotenvy = "0.15.7"
 rustls-pemfile = "2.1.3"
+thiserror = "1.0.64"
 tokio = { version = "1", features = ["full"] }
 tokio-rustls = "0.26.0"
+tracing = "0.1.40"
+tracing-error = "0.2.0"
+tracing-subscriber = "0.3.18"
+tracing_spanned = { git = "https://github.com/comnipl/tracing_spanned", rev = "6fed6097d13d117e4d35120f56450b156c33b77e" }

clocking-server/src/cert.rs

@@ -0,0 +1,34 @@
+use crate::err::ClockerError;
+
+use std::fs::File;
+use std::io::BufReader;
+use tokio_rustls::rustls::pki_types::{CertificateDer, PrivateKeyDer};
+use tracing::instrument;
+use tracing_spanned::SpanErr;
+
+#[instrument(skip_all, name = "read_cert_file", level = "trace")]
+pub fn read_cert_file(
+    cert_path: String,
+) -> Result<Vec<CertificateDer<'static>>, SpanErr<ClockerError>> {
+    let mut cert_file = File::open(cert_path).map_err(ClockerError::LoadCertFile)?;
+
+    let cert = rustls_pemfile::certs(&mut BufReader::new(&mut cert_file))
+        .collect::<Result<Vec<_>, _>>()
+        .map_err(ClockerError::LoadCertFile)?;
+
+    Ok(cert)
+}
+
+#[instrument(skip_all, name = "read_private_key_file", level = "trace")]
+pub fn read_private_key_file(
+    private_key_path: String,
+) -> Result<PrivateKeyDer<'static>, SpanErr<ClockerError>> {
+    let mut private_key_file =
+        File::open(private_key_path).map_err(ClockerError::LoadPrivateKeyFile)?;
+
+    let private_key = rustls_pemfile::private_key(&mut BufReader::new(&mut private_key_file))
+        .map_err(ClockerError::LoadPrivateKeyFile)?
+        .ok_or(ClockerError::ReadPrivateKeyPEMSection)?;
+
+    Ok(private_key)
+}

clocking-server/src/err.rs

@@ -0,0 +1,29 @@
+use std::{io, string::FromUtf8Error};
+
+use thiserror::Error;
+use tokio_rustls::rustls;
+use tracing_subscriber::util::TryInitError;
+
+#[derive(Error, Debug)]
+pub enum ClockerError {
+    #[error("initialize tracing subscriber error: {0}")]
+    InitializeTracingSubscriber(TryInitError),
+    #[error("create tcp listener error: {0}, port: {1}")]
+    CreateTCPListener(io::Error, u16),
+    #[error("failed to accept new connection")]
+    AcceptNewConnection(io::Error),
+    #[error("failed to accept new stream")]
+    AcceptNewStream(io::Error),
+    #[error("private key pem section not found")]
+    ReadPrivateKeyPEMSection,
+    #[error("build tls server error: {0}")]
+    BuildServer(rustls::Error),
+    #[error("failed to load cert file: {0}")]
+    LoadCertFile(io::Error),
+    #[error("failed to load private key file: {0}")]
+    LoadPrivateKeyFile(io::Error),
+    #[error("failed to read buffer: {0}")]
+    ReadBuffer(io::Error),
+    #[error("failed to convert buffer to string: {0}")]
+    ConvertBufferToString(FromUtf8Error),
+}