Adding env_logger

Cargo.toml

@@ -13,7 +13,9 @@ edition = "2021"
 [dependencies]
 bincode = "1"
 chrono = "0.4.31"
+env_logger = "0.10.2"
 futures = "0.3"
+log = "0.4" # for env_logger
 rayon = "1.7.0"
 reqwest = { version = "0.11" }
 serde = "1"

src/env_logger.rs

@@ -0,0 +1,24 @@
+use log::{debug, error, info};
+
+// env_logger
+// https://docs.rs/env_logger/latest/env_logger/#
+
+#[test]
+fn ex1() {
+    env_logger::init();
+    // By order of importance:
+    error!("this is printed by default");
+    info!("this is info {}", "message");
+    debug!("this is a debug {}", "message");
+}
+    // $ RUST_LOG=error cargo r ...
+    // [2023-11-09T02:12:24Z ERROR main] this is printed by default
+
+    // $ RUST_LOG=info cargo r ...
+    // [2023-11-09T02:12:24Z ERROR main] this is printed by default
+    // [2023-11-09T02:12:24Z INFO main] this is info
+
+    // $ RUST_LOG=debug cargo r ...
+    // [2023-11-09T02:12:24Z ERROR main] this is printed by default
+    // [2023-11-09T02:12:24Z INFO main] this is info
+    // [2023-11-09T02:12:24Z DEBUG main] this is a debug message

src/lib.rs

@@ -15,6 +15,7 @@ mod concurrency;
 mod const_fn;
 mod drop_aka_dtor;
 mod r#enum;
+mod env_logger;
 mod error_handling;
 mod func_ptr;
 mod int_overflow;