cache results for 10 minutes

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wttrbar"
-version = "0.7.0"
+version = "0.7.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

main.rs

@@ -1,6 +1,9 @@
 use core::time;
 use std::collections::HashMap;
+use std::fs::{metadata, read_to_string, File};
+use std::io::Write;
 use std::thread;
+use std::time::{Duration, SystemTime};
 
 use chrono::prelude::*;
 use clap::Parser;
@@ -127,28 +130,49 @@ fn main() {
 
     let mut data = HashMap::new();
 
-    let weather_url = format!(
-        "https://wttr.in/{}?format=j1",
-        args.location.unwrap_or(String::new())
-    );
+    let location = args.location.unwrap_or(String::new());
+    let weather_url = format!("https://wttr.in/{}?format=j1", location);
+    let cachefile = format!("/tmp/wttrbar-{}.json", location);
 
     let mut iterations = 0;
     let threshold = 20;
+
+    let is_cache_file_recent = if let Ok(metadata) = metadata(&cachefile) {
+        let ten_minutes_ago = SystemTime::now() - Duration::from_secs(600);
+        metadata
+            .modified()
+            .map_or(false, |mod_time| mod_time > ten_minutes_ago)
+    } else {
+        false
+    };
+
     let client = Client::new();
-    let weather = loop {
-        match client.get(&weather_url).send() {
-            Ok(response) => break response.json::<Value>().unwrap(),
-            Err(_) => {
-                iterations += 1;
-                thread::sleep(time::Duration::from_millis(500 * iterations));
-
-                if iterations == threshold {
-                    panic!("No response from endpoint!");
+    let weather = if is_cache_file_recent {
+        let json_str = read_to_string(&cachefile).unwrap();
+        serde_json::from_str::<serde_json::Value>(&json_str).unwrap()
+    } else {
+        loop {
+            match client.get(&weather_url).send() {
+                Ok(response) => break response.json::<Value>().unwrap(),
+                Err(_) => {
+                    iterations += 1;
+                    thread::sleep(time::Duration::from_millis(500 * iterations));
+
+                    if iterations == threshold {
+                        panic!("No response from endpoint!");
+                    }
                 }
             }
         }
     };
 
+    if !is_cache_file_recent {
+        let mut file = File::create(&cachefile)
+            .expect(format!("Unable to create cache file at {}", cachefile).as_str());
+
+        file.write_all(serde_json::to_string_pretty(&weather).unwrap().as_bytes())
+            .expect(format!("Unable to write cache file at {}", cachefile).as_str());
+    }
     let current_condition = &weather["current_condition"][0];
     let feels_like = if args.fahrenheit {
         current_condition["FeelsLikeF"].as_str().unwrap()