Implement simple parser for update interval duration

Cargo.lock

@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "0.7.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc936419f96fa211c1b9166887b38e5e40b19958e5b895be7c1f93adec7071ac"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "android_system_properties"
 version = "0.1.5"
@@ -59,6 +68,7 @@ version = "0.1.0"
 dependencies = [
  "chrono",
  "dirs",
+ "regex",
  "reqwest",
  "serde",
  "serde_derive",
@@ -546,6 +556,23 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "regex"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e076559ef8e241f2ae3479e36f97bd5741c0330689e217ad51ce2c76808b868a"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "456c603be3e8d448b072f410900c09faf164fbce2d480456f50eea6e25f9c848"
+
 [[package]]
 name = "reqwest"
 version = "0.11.13"

Cargo.toml

@@ -8,6 +8,7 @@ edition = "2021"
 [dependencies]
 chrono = { version = "*", features = ["serde"] }
 dirs = "4"
+regex = "1.7"
 reqwest = { version = "*", features = ["json", "rustls-tls"], default-features = false }
 serde = { version = "1", features = ["derive"] }
 serde_json = "*"

README.adoc

@@ -31,6 +31,14 @@ url = "tcp://app.example.com:12345"
 check_type = "Tcp"
 ----
 
+The value for `interval` can be set by using plain seconds or using units of `h`, `m` and `s`. Unparseable values will
+default to 60 seconds.
+
+----
+# Update interval using value with units. Default value if not set is 60 sec.
+interval = 2m30s
+----
+
 Each host or application to be checked consists of `name` and `url`.
 
 You can optionally specify `check_type`:
@@ -42,7 +50,7 @@ You can optionally specify `check_type`:
   ** `Down`: No response.
 * `Tcp`: Checks if TCP connection to given host and port can be established
 
-To use more than one configuration, pass the config file location as first argument to the application.
+To use more than one configuration, pass the config file location to be used as first argument to the application.
 
 ----
 $ checkbar /etc/checkbar_example.toml

src/config.rs

@@ -1,9 +1,11 @@
+use regex::Regex;
 use serde::Deserialize;
+use std::time::Duration;
 use std::{env, fs};
 
 #[derive(Deserialize)]
 pub struct Config {
-    pub interval: Option<u64>,
+    pub interval: Option<String>,
     pub colors: Option<ColorConfig>,
     pub checks: Vec<CheckConfig>,
 }
@@ -57,3 +59,79 @@ pub fn get_config() -> Config {
         },
     }
 }
+
+pub fn parse_duration(value: Option<String>) -> Duration {
+    let mut result = 0;
+    let value = match &value {
+        Some(value) => {
+            let result = value;
+            result.as_str()
+        }
+        _ => return Duration::from_secs(60),
+    };
+    if let Ok(re) = Regex::new(r"^((?P<hours>\d+)h)?((?P<minutes>\d+)m)?((?P<seconds>\d+)s?)?$") {
+        if re.is_match(value) {
+            let parts = re.captures_iter(value).nth(0).unwrap();
+            if let Some(hours) = parts.name("hours") {
+                result += match u64::from_str_radix(hours.as_str(), 10) {
+                    Ok(value) => value * 60 * 60,
+                    _ => 0,
+                };
+            }
+            if let Some(minutes) = parts.name("minutes") {
+                result += match u64::from_str_radix(minutes.as_str(), 10) {
+                    Ok(value) => value * 60,
+                    _ => 0,
+                };
+            }
+            if let Some(seconds) = parts.name("seconds") {
+                result += match u64::from_str_radix(seconds.as_str(), 10) {
+                    Ok(value) => value,
+                    _ => 0,
+                };
+            }
+        } else {
+            return Duration::from_secs(60);
+        }
+    }
+    Duration::from_secs(result)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::config::parse_duration;
+    use std::time::Duration;
+
+    #[test]
+    fn test_should_parse_durations() {
+        assert_eq!(
+            parse_duration(Some("1m30s".to_string())),
+            Duration::from_secs(90)
+        );
+        assert_eq!(
+            parse_duration(Some("2m".to_string())),
+            Duration::from_secs(120)
+        );
+        assert_eq!(
+            parse_duration(Some("1h1m1s".to_string())),
+            Duration::from_secs(3661)
+        );
+        assert_eq!(
+            parse_duration(Some("90".to_string())),
+            Duration::from_secs(90)
+        );
+    }
+
+    #[test]
+    fn test_should_return_default_for_unparseable_durations() {
+        assert_eq!(parse_duration(None), Duration::from_secs(60));
+        assert_eq!(
+            parse_duration(Some("invalid".to_string())),
+            Duration::from_secs(60)
+        );
+        assert_eq!(
+            parse_duration(Some("1x30m10q".to_string())),
+            Duration::from_secs(60)
+        );
+    }
+}

src/main.rs

@@ -2,14 +2,13 @@ mod checker;
 mod config;
 
 use std::process;
-use std::time::Duration;
 
 use serde::Deserialize;
 use serde_json::json;
 use tokio::task;
 
 use crate::checker::{ActuatorChecker, CheckResult, HttpChecker, TcpChecker};
-use crate::config::{get_config, CheckConfig, CheckType};
+use crate::config::{get_config, parse_duration, CheckConfig, CheckType};
 
 #[derive(Deserialize)]
 struct ClickEvent {
@@ -102,7 +101,7 @@ async fn main() {
         loop {
             let config = get_config();
             print_states(&config.checks).await;
-            std::thread::sleep(Duration::from_secs(config.interval.unwrap_or(60)));
+            std::thread::sleep(parse_duration(config.interval));
         }
     });