feat(global) better logging, add several fields for get_post api

- add sub_title, category, header_img to `get_post`

backend/src/logger.rs

@@ -1,14 +1,13 @@
 use std::{env, io};
 
 use chrono::Local;
-use tracing::{error, info, Level};
+use tracing::info;
 use tracing_appender::{non_blocking, rolling};
 use tracing_appender::non_blocking::WorkerGuard;
 use tracing_subscriber::{fmt, Registry};
 use tracing_subscriber::fmt::format::Writer;
 use tracing_subscriber::fmt::MakeWriter;
 use tracing_subscriber::fmt::time::FormatTime;
-use tracing_subscriber::fmt::writer::MakeWriterExt;
 use tracing_subscriber::layer::SubscriberExt;
 
 use crate::constants::GLOBAL_TIME_FORMAT;
@@ -21,7 +20,7 @@ impl FormatTime for LocalTimer {
     }
 }
 
-type LogWriter = dyn for<'writer> MakeWriter<'writer, Writer = dyn io::Write + 'static> + 'static;
+type _LogWriter = dyn for<'writer> MakeWriter<'writer, Writer = dyn io::Write + 'static> + 'static;
 
 pub fn init() -> (WorkerGuard, WorkerGuard) {
     let log_path = env::var("LOG_ROOT_DIR").unwrap_or_else(|e| {
@@ -31,10 +30,8 @@ pub fn init() -> (WorkerGuard, WorkerGuard) {
     let log_path = format!("{}/backend", log_path);
 
     let (info_log_writer, info_guard) = non_blocking(rolling::never(&log_path, "info.log"));
-    // let info_log = info_log.with_max_level(Level::TRACE);
 
     let (err_log_writer, error_guard) = non_blocking(rolling::never(&log_path, "error.log"));
-    // let error_log = error_logging_handle.with_filter(|log| log.level().eq(&Level::ERROR));
 
     let log_format = tracing_subscriber::fmt::format()
         .with_level(true)
@@ -42,12 +39,10 @@ pub fn init() -> (WorkerGuard, WorkerGuard) {
         .with_source_location(true)
         .with_timer(LocalTimer);
 
-    // todo: separate errors/warnings/info logs
     let subscribers = Registry::default()
         .with(
             fmt::Layer::default()
                 .with_writer(info_log_writer)
-                // .with_max_level(Level::TRACE)
                 .with_ansi(false),
         )
         .with(