From 5cf2b0c5689307b5bec113dff551c30ca8649ab6 Mon Sep 17 00:00:00 2001
From: Jun Kurihara <junkurihara@users.noreply.github.com>
Date: Mon, 28 Apr 2025 19:09:48 +0900
Subject: [PATCH] wip: impelement file logger

---
 README.md           |  4 ++--
 rpxy-bin/src/log.rs | 37 ++++++++++++++++++++++++++++++++-----
 2 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index 2f90401..e114859 100644
--- a/README.md
+++ b/README.md
@@ -97,8 +97,8 @@ Options:
 If you set `--log-dir=<log_dir>`, the log files are created in the specified directory. Otherwise, the log is printed to stdout.
 
 - `${log_dir}/access.log` for access log
-- `${log_dir}/error.log` for error log
-- `${log_dir}/rpxy.log` for system log
+<!-- - `${log_dir}/error.log` for error log -->
+- `${log_dir}/rpxy.log` for system and error log
 
 That's all!
 
diff --git a/rpxy-bin/src/log.rs b/rpxy-bin/src/log.rs
index 3a9d6bd..16a6b60 100644
--- a/rpxy-bin/src/log.rs
+++ b/rpxy-bin/src/log.rs
@@ -6,14 +6,30 @@ pub use tracing::{debug, error, info, warn};
 
 /// Initialize the logger with the RUST_LOG environment variable.
 pub fn init_logger(log_dir_path: Option<&str>) {
-  if log_dir_path.is_some() {
-    // TODO:
-    println!("Activate logging to files")
-  }
-
   let level_string = std::env::var("RUST_LOG").unwrap_or_else(|_| "info".to_string());
   let level = tracing::Level::from_str(level_string.as_str()).unwrap_or(tracing::Level::INFO);
 
+  match log_dir_path {
+    None => {
+      // log to stdout
+      init_stdio_logger(level);
+    }
+    Some(log_dir_path) => {
+      // log to files
+      println!("Activate logging to files: {log_dir_path}");
+      init_file_logger(level, log_dir_path);
+    }
+  }
+}
+
+/// file logging
+fn init_file_logger(level: tracing::Level, log_dir_path: &str) {
+  // TODO: implement
+  init_stdio_logger(level);
+}
+
+/// stdio logging
+fn init_stdio_logger(level: tracing::Level) {
   // This limits the logger to emits only this crate with any level above RUST_LOG, for included crates it will emit only ERROR (in prod)/INFO (in dev) or above level.
   let stdio_layer = fmt::layer().with_level(true).with_thread_ids(false);
   if level <= tracing::Level::INFO {
@@ -47,3 +63,14 @@ pub fn init_logger(log_dir_path: Option<&str>) {
     tracing_subscriber::registry().with(stdio_layer).init();
   };
 }
+
+#[inline]
+/// Create a file for logging
+fn open_log_file(path: &str) -> std::fs::File {
+  // crate a file if it does not exist
+  std::fs::OpenOptions::new()
+    .create(true)
+    .append(true)
+    .open(path)
+    .expect("Failed to open the log file")
+}