new: added command-line option for config file path (#233)

Cargo.toml

@@ -4,7 +4,7 @@ members = [".", "crate/encstr"]
 [workspace.package]
 repository = "https://github.com/pamburus/hl"
 authors = ["Pavel Ivanov <[email protected]>"]
-version = "0.29.0-alpha.4"
+version = "0.29.0-alpha.5"
 edition = "2021"
 license = "MIT"
 
@@ -40,7 +40,7 @@ chrono = { version = "0.4", default-features = false, features = [
     "std",
 ] }
 chrono-tz = { version = "0", features = ["serde"] }
-clap = { version = "4", features = ["wrap_help", "derive", "env"] }
+clap = { version = "4", features = ["wrap_help", "derive", "env", "string"] }
 clap_complete = "4"
 closure = "0"
 collection_macros = "0"

README.md

@@ -464,6 +464,7 @@ Arguments:
   [FILE]...  Files to process
 
 Options:
+      --config <FILE>                    Configuration file path [env: HL_CONFIG=] [default: ~/.config/hl/config.yaml]
   -s, --sort                             Sort messages chronologically
   -F, --follow                           Follow input streams and sort messages chronologically during time frame set by --sync-interval-ms option
       --tail <N>                         Number of last messages to preload from each file in --follow mode [default: 10]

src/cli.rs

@@ -2,7 +2,7 @@
 use std::path::PathBuf;
 
 // third-party imports
-use clap::{value_parser, ArgAction, Parser, ValueEnum};
+use clap::{value_parser, ArgAction, Args, Parser, ValueEnum};
 use clap_complete::Shell;
 use std::num::NonZeroUsize;
 
@@ -16,10 +16,76 @@ use crate::{
 
 // ---
 
+#[derive(Args)]
+pub struct BootstrapArgs {
+    /// Configuration file path.
+    #[arg(long, overrides_with = "config", value_name = "FILE", env = "HL_CONFIG", default_value = default_config_path(), num_args=1)]
+    pub config: String,
+}
+
+/// JSON and logfmt log converter to human readable representation.
+#[derive(Parser)]
+#[clap(version, disable_help_flag = true)]
+pub struct BootstrapOpt {
+    #[command(flatten)]
+    pub args: BootstrapArgs,
+}
+
+impl BootstrapOpt {
+    pub fn parse() -> Self {
+        Self::parse_from(Self::args())
+    }
+
+    pub fn args() -> Vec<String> {
+        let mut args = std::env::args();
+        let Some(first) = args.next() else {
+            return vec![];
+        };
+
+        let mut result = vec![first];
+        let mut follow_up = false;
+
+        while let Some(arg) = args.next() {
+            match (arg.as_bytes(), follow_up) {
+                (b"--", _) => {
+                    break;
+                }
+                ([b'-', b'-', b'c', b'o', b'n', b'f', b'i', b'g', b'=', ..], _) => {
+                    result.push(arg);
+                    follow_up = false;
+                }
+                (b"--config", _) => {
+                    result.push(arg);
+                    follow_up = true;
+                }
+                ([b'-'], true) => {
+                    result.push(arg);
+                    follow_up = false;
+                }
+                ([b'-', ..], true) => {
+                    follow_up = false;
+                }
+                (_, true) => {
+                    result.push(arg);
+                    follow_up = false;
+                }
+                _ => {}
+            }
+        }
+
+        result
+    }
+}
+
+// ---
+
 /// JSON and logfmt log converter to human readable representation.
 #[derive(Parser)]
 #[clap(version, disable_help_flag = true)]
 pub struct Opt {
+    #[command(flatten)]
+    pub bootstrap: BootstrapArgs,
+
     /// Sort messages chronologically.
     #[arg(long, short = 's', overrides_with = "sort")]
     pub sort: bool,
@@ -125,7 +191,7 @@ pub struct Opt {
     /// Color theme.
     #[arg(
         long,
-        default_value_t = config::get().theme.clone(),
+        default_value_t = config::global::get().theme.clone(),
         env = "HL_THEME",
         overrides_with="theme",
         help_heading = heading::OUTPUT
@@ -160,7 +226,7 @@ pub struct Opt {
         env = "HL_FLATTEN",
         value_name = "WHEN",
         value_enum,
-        default_value_t = config::get().formatting.flatten.as_ref().map(|x| match x{
+        default_value_t = config::global::get().formatting.flatten.as_ref().map(|x| match x{
             settings::FlattenOption::Never => FlattenOption::Never,
             settings::FlattenOption::Always => FlattenOption::Always,
         }).unwrap_or(FlattenOption::Always),
@@ -174,7 +240,7 @@ pub struct Opt {
         short,
         long,
         env="HL_TIME_FORMAT",
-        default_value_t = config::get().time_format.clone(),
+        default_value_t = config::global::get().time_format.clone(),
         overrides_with = "time_format",
         value_name = "FORMAT",
         help_heading = heading::OUTPUT
@@ -186,7 +252,7 @@ pub struct Opt {
         long,
         short = 'Z',
         env="HL_TIME_ZONE",
-        default_value = config::get().time_zone.name(),
+        default_value = config::global::get().time_zone.name(),
         overrides_with="time_zone",
         value_name = "TZ",
         help_heading = heading::OUTPUT
@@ -408,3 +474,11 @@ fn parse_non_zero_size(s: &str) -> std::result::Result<NonZeroUsize, NonZeroSize
         Err(NonZeroSizeParseError::ZeroSize)
     }
 }
+
+fn default_config_path() -> clap::builder::OsStr {
+    if let Some(dirs) = config::app_dirs() {
+        dirs.config_dir.join("config.yaml").into_os_string().into()
+    } else {
+        "".into()
+    }
+}

src/config.rs

@@ -1,31 +1,51 @@
+// std imports
+use std::sync::Mutex;
+
 // third-party imports
 use once_cell::sync::Lazy;
 use platform_dirs::AppDirs;
 
 // local imports
-use crate::settings::Settings;
+use crate::{error::Result, settings::Settings};
 
 // ---
 
 pub const APP_NAME: &str = "hl";
 
-static CONFIG: Lazy<Settings> = Lazy::new(load);
-static DEFAULT: Lazy<Settings> = Lazy::new(Settings::default);
-
-pub fn get() -> &'static Settings {
-    &CONFIG
+/// Get the default settings.
+pub fn default() -> &'static Settings {
+    Default::default()
 }
 
-pub fn default() -> &'static Settings {
-    &DEFAULT
+/// Load settings from the given file or the default configuration file per platform.
+pub fn load(path: String) -> Result<Settings> {
+    if path.is_empty() {
+        return Ok(Default::default());
+    }
+
+    Settings::load(&path)
 }
 
-pub fn app_dirs() -> AppDirs {
-    AppDirs::new(Some(APP_NAME), true).unwrap()
+/// Get the application platform-specific directories.
+pub fn app_dirs() -> Option<AppDirs> {
+    AppDirs::new(Some(APP_NAME), true)
 }
 
-// ---
+pub mod global {
+    use super::*;
+
+    static PENDING: Mutex<Option<Settings>> = Mutex::new(None);
+    static RESOLVED: Lazy<Settings> = Lazy::new(|| PENDING.lock().unwrap().take().unwrap_or_default());
+
+    /// Call initialize before any calls to get otherwise it will have no effect.
+    pub fn initialize(settings: Settings) {
+        *PENDING.lock().unwrap() = Some(settings);
+    }
 
-fn load() -> Settings {
-    Settings::load(&app_dirs()).unwrap()
+    /// Get the resolved settings.
+    /// If initialized was called before, then a clone of those settings will be returned.
+    /// Otherwise, the default settings will be returned.
+    pub fn get() -> &'static Settings {
+        &RESOLVED
+    }
 }

src/error.rs

@@ -95,6 +95,14 @@ pub enum Error {
     ParseFloatError(#[from] ParseFloatError),
     #[error(transparent)]
     ParseIntError(#[from] ParseIntError),
+    #[error("failed to detect application directories")]
+    AppDirs,
+}
+
+impl Error {
+    pub fn log(&self) {
+        eprintln!("{} {}", Color::LightRed.bold().paint("error:"), self);
+    }
 }
 
 /// SizeParseError is an error which may occur when parsing size.
@@ -134,3 +142,14 @@ pub struct InvalidLevelError {
 pub type Result<T> = std::result::Result<T, Error>;
 
 pub const HILITE: Color = Color::Yellow;
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_log() {
+        let err = Error::Io(std::io::Error::new(std::io::ErrorKind::Other, "test"));
+        err.log();
+    }
+}

src/main.rs

@@ -12,7 +12,6 @@ use std::{
 use chrono::Utc;
 use clap::{CommandFactory, Parser};
 use itertools::Itertools;
-use nu_ansi_term::Color;
 
 // local imports
 use hl::{
@@ -32,10 +31,10 @@ use hl::{
 // ---
 
 fn run() -> Result<()> {
-    let app_dirs = config::app_dirs();
-    let settings = config::get();
-    let opt = cli::Opt::parse();
+    let settings = config::load(cli::BootstrapOpt::parse().args.config)?;
+    config::global::initialize(settings.clone());
 
+    let opt = cli::Opt::parse();
     if opt.help {
         return cli::Opt::command().print_help().map_err(Error::Io);
     }
@@ -69,6 +68,8 @@ fn run() -> Result<()> {
         cli::ColorOption::Always => true,
         cli::ColorOption::Never => false,
     };
+
+    let app_dirs = config::app_dirs().ok_or(Error::AppDirs)?;
     let theme = if use_colors {
         let theme = &opt.theme;
         Theme::load(&app_dirs, theme)?
@@ -130,7 +131,7 @@ fn run() -> Result<()> {
     let all = || IncludeExcludeKeyFilter::new(KeyMatchOptions::default());
     let none = || all().excluded();
     let mut fields = all();
-    for (i, key) in config::get().fields.hide.iter().chain(&opt.hide).enumerate() {
+    for (i, key) in settings.fields.hide.iter().chain(&opt.hide).enumerate() {
         if key == "*" {
             fields = none();
         } else if key == "!*" {
@@ -310,7 +311,7 @@ fn run() -> Result<()> {
 
 fn main() {
     if let Err(err) = run() {
-        eprintln!("{}: {}", Color::Red.paint("error"), err);
+        err.log();
         process::exit(1);
     }
 }