Configure logging (-vv for debug level logs)

2 files changed, 50 insertions, 1 deletions

diff --git a/helix-term/Cargo.toml b/helix-term/Cargo.toml
index db1edee9..c1560ee7 100644
--- a/helix-term/Cargo.toml
+++ b/helix-term/Cargo.toml
@@ -19,10 +19,15 @@ helix-lsp = { path = "../helix-lsp"}
 anyhow = "1"
 
 smol = "1"
-num_cpus = "1.13"
+num_cpus = "1"
 # tui = { version = "0.12", default-features = false, features = ["crossterm"] }
 tui = { git = "https://github.com/fdehau/tui-rs", default-features = false, features = ["crossterm"] }
 crossterm = { version = "0.18", features = ["event-stream"] }
 clap = { version = "3.0.0-beta.2 ", default-features = false, features = ["std", "cargo"] }
 
 futures-util = "0.3"
+
+# Logging
+fern = "0.6"
+chrono = "0.4"
+log = "0.4"
diff --git a/helix-term/src/main.rs b/helix-term/src/main.rs
index de3a0175..f91c1c8f 100644
--- a/helix-term/src/main.rs
+++ b/helix-term/src/main.rs
@@ -11,6 +11,39 @@ use anyhow::Error;
 
 static EX: smol::Executor = smol::Executor::new();
 
+fn setup_logging(verbosity: u64) -> Result<(), fern::InitError> {
+    let mut base_config = fern::Dispatch::new();
+
+    // Let's say we depend on something which whose "info" level messages are too
+    // verbose to include in end-user output. If we don't need them,
+    // let's not include them.
+    // .level_for("overly-verbose-target", log::LevelFilter::Warn)
+
+    base_config = match verbosity {
+        0 => base_config.level(log::LevelFilter::Warn),
+        1 => base_config.level(log::LevelFilter::Info),
+        2 => base_config.level(log::LevelFilter::Debug),
+        _3_or_more => base_config.level(log::LevelFilter::Trace),
+    };
+
+    // Separate file config so we can include year, month and day in file logs
+    let file_config = fern::Dispatch::new()
+        .format(|out, message, record| {
+            out.finish(format_args!(
+                "{} {} [{}] {}",
+                chrono::Local::now().format("%Y-%m-%dT%H:%M:%S%.3f"),
+                record.target(),
+                record.level(),
+                message
+            ))
+        })
+        .chain(fern::log_file("helix.log")?);
+
+    base_config.chain(file_config).apply()?;
+
+    Ok(())
+}
+
 fn main() -> Result<(), Error> {
     let args = clap::app_from_crate!()
         .arg(
@@ -20,8 +53,19 @@ fn main() -> Result<(), Error> {
                 .multiple(true)
                 .index(1),
         )
+        .arg(
+            Arg::new("verbose")
+                .about("Increases logging verbosity each use for up to 3 times")
+                .short('v')
+                .takes_value(false)
+                .multiple_occurrences(true),
+        )
         .get_matches();
 
+    let verbosity: u64 = args.occurrences_of("verbose");
+
+    setup_logging(verbosity).expect("failed to initialize logging.");
+
     for _ in 0..num_cpus::get() {
         std::thread::spawn(move || smol::block_on(EX.run(smol::future::pending::<()>())));
     }