Add CachedCloudflareFilter

Introduce CachedCloudflareFilter that caches Cloudflare IP ranges and
refreshes every 24 hours. If a refresh fails the previously cached
ranges
are retained and a warning is emitted. Wire the cache through main and
updater so Cloudflare fetches reuse the cached result. Update tests and
bump crate version to 2.0.7

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cloudflare-ddns"
-version = "2.0.6"
+version = "2.0.7"
 edition = "2021"
 description = "Access your home network remotely via a custom domain name without a static IP"
 license = "GPL-3.0"

src/cf_ip_filter.rs

@@ -1,7 +1,7 @@
 use crate::pp::{self, PP};
 use reqwest::Client;
 use std::net::IpAddr;
-use std::time::Duration;
+use std::time::{Duration, Instant};
 
 const CF_IPV4_URL: &str = "https://www.cloudflare.com/ips-v4";
 const CF_IPV6_URL: &str = "https://www.cloudflare.com/ips-v6";
@@ -157,6 +157,62 @@ impl CloudflareIpFilter {
     }
 }
 
+/// Refresh interval for Cloudflare IP ranges (24 hours).
+const CF_RANGE_REFRESH: Duration = Duration::from_secs(24 * 60 * 60);
+
+/// Cached wrapper around [`CloudflareIpFilter`].
+///
+/// Fetches once, then re-uses the cached ranges for [`CF_RANGE_REFRESH`].
+/// If a refresh fails, the previously cached ranges are kept.
+pub struct CachedCloudflareFilter {
+    filter: Option<CloudflareIpFilter>,
+    fetched_at: Option<Instant>,
+}
+
+impl CachedCloudflareFilter {
+    pub fn new() -> Self {
+        Self {
+            filter: None,
+            fetched_at: None,
+        }
+    }
+
+    /// Return a reference to the current filter, refreshing if stale or absent.
+    pub async fn get(
+        &mut self,
+        client: &Client,
+        timeout: Duration,
+        ppfmt: &PP,
+    ) -> Option<&CloudflareIpFilter> {
+        let stale = match self.fetched_at {
+            Some(t) => t.elapsed() >= CF_RANGE_REFRESH,
+            None => true,
+        };
+
+        if stale {
+            match CloudflareIpFilter::fetch(client, timeout, ppfmt).await {
+                Some(new_filter) => {
+                    self.filter = Some(new_filter);
+                    self.fetched_at = Some(Instant::now());
+                }
+                None => {
+                    if self.filter.is_some() {
+                        ppfmt.warningf(
+                            pp::EMOJI_WARNING,
+                            "Failed to refresh Cloudflare IP ranges; using cached version",
+                        );
+                        // Keep using cached filter, but don't update fetched_at
+                        // so we retry next cycle.
+                    }
+                    // If no cached filter exists, return None (caller handles fail-safe).
+                }
+            }
+        }
+
+        self.filter.as_ref()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/main.rs

@@ -116,12 +116,14 @@ async fn main() {
     // Start heartbeat
     heartbeat.start().await;
 
+    let mut cf_cache = cf_ip_filter::CachedCloudflareFilter::new();
+
     if app_config.legacy_mode {
         // --- Legacy mode (original cloudflare-ddns behavior) ---
-        run_legacy_mode(&app_config, &handle, &notifier, &heartbeat, &ppfmt, running).await;
+        run_legacy_mode(&app_config, &handle, &notifier, &heartbeat, &ppfmt, running, &mut cf_cache).await;
     } else {
         // --- Env var mode (cf-ddns behavior) ---
-        run_env_mode(&app_config, &handle, &notifier, &heartbeat, &ppfmt, running).await;
+        run_env_mode(&app_config, &handle, &notifier, &heartbeat, &ppfmt, running, &mut cf_cache).await;
     }
 
     // On shutdown: delete records if configured
@@ -143,6 +145,7 @@ async fn run_legacy_mode(
     heartbeat: &Heartbeat,
     ppfmt: &PP,
     running: Arc<AtomicBool>,
+    cf_cache: &mut cf_ip_filter::CachedCloudflareFilter,
 ) {
     let legacy = match &config.legacy_config {
         Some(l) => l,
@@ -165,7 +168,7 @@ async fn run_legacy_mode(
         }
 
         while running.load(Ordering::SeqCst) {
-            updater::update_once(config, handle, notifier, heartbeat, ppfmt).await;
+            updater::update_once(config, handle, notifier, heartbeat, cf_cache, ppfmt).await;
 
             for _ in 0..legacy.ttl {
                 if !running.load(Ordering::SeqCst) {
@@ -175,7 +178,7 @@ async fn run_legacy_mode(
             }
         }
     } else {
-        updater::update_once(config, handle, notifier, heartbeat, ppfmt).await;
+        updater::update_once(config, handle, notifier, heartbeat, cf_cache, ppfmt).await;
     }
 }
 
@@ -186,11 +189,12 @@ async fn run_env_mode(
     heartbeat: &Heartbeat,
     ppfmt: &PP,
     running: Arc<AtomicBool>,
+    cf_cache: &mut cf_ip_filter::CachedCloudflareFilter,
 ) {
     match &config.update_cron {
         CronSchedule::Once => {
             if config.update_on_start {
-                updater::update_once(config, handle, notifier, heartbeat, ppfmt).await;
+                updater::update_once(config, handle, notifier, heartbeat, cf_cache, ppfmt).await;
             }
         }
         schedule => {
@@ -206,7 +210,7 @@ async fn run_env_mode(
 
             // Update on start if configured
             if config.update_on_start {
-                updater::update_once(config, handle, notifier, heartbeat, ppfmt).await;
+                updater::update_once(config, handle, notifier, heartbeat, cf_cache, ppfmt).await;
             }
 
             // Main loop
@@ -233,7 +237,7 @@ async fn run_env_mode(
                     return;
                 }
 
-                updater::update_once(config, handle, notifier, heartbeat, ppfmt).await;
+                updater::update_once(config, handle, notifier, heartbeat, cf_cache, ppfmt).await;
             }
         }
     }

src/updater.rs

@@ -1,4 +1,4 @@
-use crate::cf_ip_filter::CloudflareIpFilter;
+use crate::cf_ip_filter::CachedCloudflareFilter;
 use crate::cloudflare::{CloudflareHandle, SetResult};
 use crate::config::{AppConfig, LegacyCloudflareEntry, LegacySubdomainEntry};
 use crate::domain::make_fqdn;
@@ -16,6 +16,7 @@ pub async fn update_once(
     handle: &CloudflareHandle,
     notifier: &CompositeNotifier,
     heartbeat: &Heartbeat,
+    cf_cache: &mut CachedCloudflareFilter,
     ppfmt: &PP,
 ) -> bool {
     let detection_client = Client::builder()
@@ -28,7 +29,7 @@ pub async fn update_once(
     let mut notify = false; // NEW: track meaningful events
 
     if config.legacy_mode {
-        all_ok = update_legacy(config, ppfmt).await;
+        all_ok = update_legacy(config, cf_cache, ppfmt).await;
     } else {
         // Detect IPs for each provider
         let mut detected_ips: HashMap<IpType, Vec<IpAddr>> = HashMap::new();
@@ -69,7 +70,7 @@ pub async fn update_once(
         // Filter out Cloudflare IPs if enabled
         if config.reject_cloudflare_ips {
             if let Some(cf_filter) =
-                CloudflareIpFilter::fetch(&detection_client, config.detection_timeout, ppfmt).await
+                cf_cache.get(&detection_client, config.detection_timeout, ppfmt).await
             {
                 for (ip_type, ips) in detected_ips.iter_mut() {
                     let before_count = ips.len();
@@ -235,7 +236,7 @@ pub async fn update_once(
 /// IP-family-bound clients (0.0.0.0 for IPv4, [::] for IPv6). This prevents the old
 /// wrong-family warning on dual-stack hosts and honours `ip4_provider`/`ip6_provider`
 /// overrides from config.json.
-async fn update_legacy(config: &AppConfig, ppfmt: &PP) -> bool {
+async fn update_legacy(config: &AppConfig, cf_cache: &mut CachedCloudflareFilter, ppfmt: &PP) -> bool {
     let legacy = match &config.legacy_config {
         Some(l) => l,
         None => return false,
@@ -301,7 +302,7 @@ async fn update_legacy(config: &AppConfig, ppfmt: &PP) -> bool {
     if config.reject_cloudflare_ips {
         let before_count = ips.len();
         if let Some(cf_filter) =
-            CloudflareIpFilter::fetch(&detection_client, config.detection_timeout, ppfmt).await
+            cf_cache.get(&detection_client, config.detection_timeout, ppfmt).await
         {
             ips.retain(|key, ip_info| {
                 if let Ok(addr) = ip_info.ip.parse::<std::net::IpAddr>() {
@@ -802,7 +803,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -850,7 +852,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -894,7 +897,8 @@ mod tests {
         let ppfmt = pp();
 
         // all_ok = true because no zone-level errors occurred (empty ips just noop or warn)
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         // Providers with None are not inserted in loop, so no IP detection warning is emitted,
         // no detected_ips entry is created, and set_ips is called with empty slice -> Noop.
         assert!(ok);
@@ -943,7 +947,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(!ok, "Expected false when zone is not found");
     }
 
@@ -992,7 +997,8 @@ mod tests {
         let ppfmt = pp();
 
         // dry_run returns Updated from set_ips (it signals intent), all_ok should be true
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -1057,7 +1063,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -1110,7 +1117,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -1149,7 +1157,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(!ok, "Expected false when WAF list is not found");
     }
 
@@ -1233,7 +1242,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -1249,7 +1259,8 @@ mod tests {
         let heartbeat = empty_heartbeat();
         let ppfmt = pp();
 
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
 
@@ -1633,7 +1644,8 @@ mod tests {
         let ppfmt = pp();
 
         // set_ips with empty ips and no existing records = Noop; all_ok = true
-        let ok = update_once(&config, &cf, &notifier, &heartbeat, &ppfmt).await;
+        let mut cf_cache = CachedCloudflareFilter::new();
+        let ok = update_once(&config, &cf, &notifier, &heartbeat, &mut cf_cache, &ppfmt).await;
         assert!(ok);
     }
     // -------------------------------------------------------