Merge pull request #5 from damus-io/#3

Improve performance with nostr event caching and better mutex design

Cargo.lock

@@ -1562,9 +1562,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.10.5"
+version = "1.10.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b91213439dad192326a0d7c6ee3955910425f441d7038e0d6933b0aec5c4517f"
+checksum = "4219d74c6b67a3654a9fbebc4b419e22126d13d2f3c4a07ee0cb61ff79a79619"
 dependencies = [
  "aho-corasick",
  "memchr",

src/api_request_handler.rs

@@ -1,4 +1,5 @@
 use crate::nip98_auth;
+use crate::notification_manager::notification_manager::UserNotificationSettings;
 use crate::relay_connection::RelayConnection;
 use http_body_util::Full;
 use hyper::body::Buf;
@@ -9,50 +10,21 @@ use hyper_tungstenite;
 
 use http_body_util::BodyExt;
 use nostr;
+use serde_json::from_value;
 
 use crate::notification_manager::NotificationManager;
 use hyper::Method;
 use log;
 use serde_json::{json, Value};
+use std::collections::HashMap;
 use std::sync::Arc;
 use thiserror::Error;
 
-struct ParsedRequest {
-    uri: String,
-    method: Method,
-    body_bytes: Option<Vec<u8>>,
-    authorized_pubkey: nostr::PublicKey,
-}
-
-impl ParsedRequest {
-    fn body_json(&self) -> Result<serde_json::Value, Box<dyn std::error::Error>> {
-        if let Some(body_bytes) = &self.body_bytes {
-            Ok(serde_json::from_slice(body_bytes)?)
-        } else {
-            Ok(json!({}))
-        }
-    }
-}
-
-struct APIResponse {
-    status: StatusCode,
-    body: Value,
-}
-
 pub struct APIHandler {
     notification_manager: Arc<NotificationManager>,
     base_url: String,
 }
 
-impl Clone for APIHandler {
-    fn clone(&self) -> Self {
-        APIHandler {
-            notification_manager: self.notification_manager.clone(),
-            base_url: self.base_url.clone(),
-        }
-    }
-}
-
 impl APIHandler {
     pub fn new(notification_manager: Arc<NotificationManager>, base_url: String) -> Self {
         APIHandler {
@@ -61,6 +33,8 @@ impl APIHandler {
         }
     }
     
+    // MARK: - HTTP handling
+
     pub async fn handle_http_request(
         &self,
         req: Request<Incoming>,
@@ -186,22 +160,37 @@ impl APIHandler {
         })
     }
     
+    // MARK: - Router
+
     async fn handle_parsed_http_request(
         &self,
         parsed_request: &ParsedRequest,
     ) -> Result<APIResponse, Box<dyn std::error::Error>> {
-        match (&parsed_request.method, parsed_request.uri.as_str()) {
+        
-            (&Method::POST, "/user-info") => self.handle_user_info(parsed_request).await,
+        if let Some(url_params) = route_match(&Method::PUT, "/user-info/:pubkey/:deviceToken", &parsed_request) {
-            (&Method::POST, "/user-info/remove") => {
+            return self.handle_user_info(parsed_request, &url_params).await;
-                self.handle_user_info_remove(parsed_request).await
         }
-            _ => Ok(APIResponse {
+        
+        if let Some(url_params) = route_match(&Method::DELETE, "/user-info/:pubkey/:deviceToken", &parsed_request) {
+            return self.handle_user_info_remove(parsed_request, &url_params).await;
+        }
+        
+        if let Some(url_params) = route_match(&Method::GET, "/user-info/:pubkey/:deviceToken/preferences", &parsed_request) {
+            return self.get_user_settings(parsed_request, &url_params).await;
+        }
+        
+        if let Some(url_params) = route_match(&Method::PUT, "/user-info/:pubkey/:deviceToken/preferences", &parsed_request) {
+            return self.set_user_settings(parsed_request, &url_params).await;
+        }
+        
+        Ok(APIResponse {
             status: StatusCode::NOT_FOUND,
             body: json!({ "error": "Not found" }),
-            }),
+        })
-        }
     }
     
+    // MARK: - Authentication
+
     async fn authenticate(
         &self,
         req: &Request<Incoming>,
@@ -221,50 +210,282 @@ impl APIHandler {
         .await)
     }
     
+    // MARK: - Endpoint handlers
+
     async fn handle_user_info(
         &self,
         req: &ParsedRequest,
+        url_params: &HashMap<&str, String>,
     ) -> Result<APIResponse, Box<dyn std::error::Error>> {
-        let body = req.body_json()?;
+        // Early return if `deviceToken` is missing
-
+        let device_token = match url_params.get("deviceToken") {
-        if let Some(device_token) = body["deviceToken"].as_str() {
+            Some(token) => token,
-            self.notification_manager.save_user_device_info(req.authorized_pubkey, device_token).await?;
+            None => return Ok(APIResponse {
-            return Ok(APIResponse {
-                status: StatusCode::OK,
-                body: json!({ "message": "User info saved successfully" }),
-            });
-        } else {
-            return Ok(APIResponse {
                 status: StatusCode::BAD_REQUEST,
-                body: json!({ "error": "deviceToken is required" }),
+                body: json!({ "error": "deviceToken is required on the URL" }),
+            }),
+        };
+    
+        // Early return if `pubkey` is missing
+        let pubkey = match url_params.get("pubkey") {
+            Some(key) => key,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "pubkey is required on the URL" }),
+            }),
+        };
+        
+        // Validate the `pubkey` and prepare it for use
+        let pubkey = match nostr::PublicKey::from_hex(pubkey) {
+            Ok(key) => key,
+            Err(_) => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "Invalid pubkey" }),
+            }),
+        };
+    
+        // Early return if `pubkey` does not match `req.authorized_pubkey`
+        if pubkey != req.authorized_pubkey {
+            return Ok(APIResponse {
+                status: StatusCode::FORBIDDEN,
+                body: json!({ "error": "Forbidden" }),
             });
         }
+        
+        // Proceed with the main logic after passing all checks
+        self.notification_manager.save_user_device_info(pubkey, device_token).await?;
+        Ok(APIResponse {
+            status: StatusCode::OK,
+            body: json!({ "message": "User info saved successfully" }),
+        })
     }
 
     async fn handle_user_info_remove(
         &self,
         req: &ParsedRequest,
+        url_params: &HashMap<&str, String>,
     ) -> Result<APIResponse, Box<dyn std::error::Error>> {
-        let body: Value = req.body_json()?;
+        // Early return if `deviceToken` is missing
+        let device_token = match url_params.get("deviceToken") {
+            Some(token) => token,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "deviceToken is required on the URL" }),
+            }),
+        };
         
-        if let Some(device_token) = body["deviceToken"].as_str() {
+        // Early return if `pubkey` is missing
-            self.notification_manager.remove_user_device_info(req.authorized_pubkey, device_token).await?;
+        let pubkey = match url_params.get("pubkey") {
+            Some(key) => key,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "pubkey is required on the URL" }),
+            }),
+        };
+        
+        // Validate the `pubkey` and prepare it for use
+        let pubkey = match nostr::PublicKey::from_hex(pubkey) {
+            Ok(key) => key,
+            Err(_) => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "Invalid pubkey" }),
+            }),
+        };
+        
+        // Early return if `pubkey` does not match `req.authorized_pubkey`
+        if pubkey != req.authorized_pubkey {
             return Ok(APIResponse {
+                status: StatusCode::FORBIDDEN,
+                body: json!({ "error": "Forbidden" }),
+            });
+        }
+        
+        // Proceed with the main logic after passing all checks
+        self.notification_manager.remove_user_device_info(pubkey, device_token).await?;
+        
+        Ok(APIResponse {
             status: StatusCode::OK,
             body: json!({ "message": "User info removed successfully" }),
+        })
+    }
+    
+    async fn set_user_settings(
+        &self,
+        req: &ParsedRequest,
+        url_params: &HashMap<&str, String>,
+    ) -> Result<APIResponse, Box<dyn std::error::Error>> {
+        // Early return if `deviceToken` is missing
+        let device_token = match url_params.get("deviceToken") {
+            Some(token) => token,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "deviceToken is required on the URL" }),
+            }),
+        };
+        
+        // Early return if `pubkey` is missing
+        let pubkey = match url_params.get("pubkey") {
+            Some(key) => key,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "pubkey is required on the URL" }),
+            }),
+        };
+        
+        // Validate the `pubkey` and prepare it for use
+        let pubkey = match nostr::PublicKey::from_hex(pubkey) {
+            Ok(key) => key,
+            Err(_) => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "Invalid pubkey" }),
+            }),
+        };
+        
+        // Early return if `pubkey` does not match `req.authorized_pubkey`
+        if pubkey != req.authorized_pubkey {
+            return Ok(APIResponse {
+                status: StatusCode::FORBIDDEN,
+                body: json!({ "error": "Forbidden" }),
             });
-        } else {
+        }
+        
+        // Proceed with the main logic after passing all checks
+        let body = req.body_json()?;
+
+        let settings: UserNotificationSettings = match from_value(body.clone()) {
+            Ok(settings) => settings,
+            Err(_) => {
                 return Ok(APIResponse {
                     status: StatusCode::BAD_REQUEST,
-                body: json!({ "error": "deviceToken is required" }),
+                    body: json!({ "error": "Invalid settings" }),
                 });
             }
+        };
+        
+        self.notification_manager.save_user_notification_settings(&req.authorized_pubkey, device_token.to_string(), settings).await?;
+        return Ok(APIResponse {
+            status: StatusCode::OK,
+            body: json!({ "message": "User settings saved successfully" }),
+        });
+    }
+    
+    async fn get_user_settings(
+        &self,
+        req: &ParsedRequest,
+        url_params: &HashMap<&str, String>,
+    ) -> Result<APIResponse, Box<dyn std::error::Error>> {
+        // Early return if `deviceToken` is missing
+        let device_token = match url_params.get("deviceToken") {
+            Some(token) => token,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "deviceToken is required on the URL" }),
+            }),
+        };
+        
+        // Early return if `pubkey` is missing
+        let pubkey = match url_params.get("pubkey") {
+            Some(key) => key,
+            None => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "pubkey is required on the URL" }),
+            }),
+        };
+        
+        // Validate the `pubkey` and prepare it for use
+        let pubkey = match nostr::PublicKey::from_hex(pubkey) {
+            Ok(key) => key,
+            Err(_) => return Ok(APIResponse {
+                status: StatusCode::BAD_REQUEST,
+                body: json!({ "error": "Invalid pubkey" }),
+            }),
+        };
+        
+        // Early return if `pubkey` does not match `req.authorized_pubkey`
+        if pubkey != req.authorized_pubkey {
+            return Ok(APIResponse {
+                status: StatusCode::FORBIDDEN,
+                body: json!({ "error": "Forbidden" }),
+            });
+        }
+        
+        // Proceed with the main logic after passing all checks
+        let settings = self.notification_manager.get_user_notification_settings(&req.authorized_pubkey, device_token.to_string()).await?;
+        
+        Ok(APIResponse {
+            status: StatusCode::OK,
+            body: json!(settings),
+        })
+    }
+}
+
+// MARK: - Extensions
+
+impl Clone for APIHandler {
+    fn clone(&self) -> Self {
+        APIHandler {
+            notification_manager: self.notification_manager.clone(),
+            base_url: self.base_url.clone(),
+        }
     }
 }
 
+// MARK: - Helper types
+
 // Define enum error types including authentication error
 #[derive(Debug, Error)]
 enum APIError {
     #[error("Authentication error: {0}")]
     AuthenticationError(String),
 }
+
+struct ParsedRequest {
+    uri: String,
+    method: Method,
+    body_bytes: Option<Vec<u8>>,
+    authorized_pubkey: nostr::PublicKey,
+}
+
+impl ParsedRequest {
+    fn body_json(&self) -> Result<serde_json::Value, Box<dyn std::error::Error>> {
+        if let Some(body_bytes) = &self.body_bytes {
+            Ok(serde_json::from_slice(body_bytes)?)
+        } else {
+            Ok(json!({}))
+        }
+    }
+}
+
+struct APIResponse {
+    status: StatusCode,
+    body: Value,
+}
+
+// MARK: - Helper functions
+ 
+/// Matches the request to a specified route, returning a hashmap of the route parameters
+/// e.g. GET /user/:id/info route against request GET /user/123/info matches to { "id": "123" }
+fn route_match<'a>(method: &Method, path: &'a str, req: &ParsedRequest) -> Option<HashMap<&'a str, String>> {
+    if method != req.method {
+        return None;
+    }
+    let mut params = HashMap::new();
+    let path_segments: Vec<&str> = path.split('/').filter(|s| !s.is_empty()).collect();
+    let req_segments: Vec<&str> = req.uri.split('/').filter(|s| !s.is_empty()).collect();
+
+    if path_segments.len() != req_segments.len() {
+        return None;
+    }
+
+    for (i, segment) in path_segments.iter().enumerate() {
+        if segment.starts_with(':') {
+            let key = &segment[1..];
+            let value = req_segments[i].to_string();
+            params.insert(key, value);
+        } else if segment != &req_segments[i] {
+            return None;
+        }
+    }
+
+    Some(params)
+}

src/lib.rs

@@ -1 +1,2 @@
 pub mod notification_manager;
+mod utils;

src/main.rs

@@ -12,6 +12,7 @@ mod notepush_env;
 use notepush_env::NotePushEnv;
 mod api_request_handler;
 mod nip98_auth;
+mod utils;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {

src/nip98_auth.rs

@@ -3,8 +3,8 @@ use nostr;
 use nostr::bitcoin::hashes::sha256::Hash as Sha256Hash;
 use nostr::bitcoin::hashes::Hash;
 use nostr::util::hex;
-use nostr::Timestamp;
 use serde_json::Value;
+use super::utils::time_delta::TimeDelta;
 
 pub async fn nip98_verify_auth_header(
     auth_header: String,
@@ -106,36 +106,3 @@ pub async fn nip98_verify_auth_header(
 
     Ok(note.pubkey)
 }
-
-struct TimeDelta {
-    delta_abs_seconds: u64,
-    negative: bool,
-}
-
-impl TimeDelta {
-    /// Safely calculate the difference between two timestamps in seconds
-    /// This function is safer against overflows than subtracting the timestamps directly
-    fn subtracting(t1: Timestamp, t2: Timestamp) -> TimeDelta {
-        if t1 > t2 {
-            TimeDelta {
-                delta_abs_seconds: (t1 - t2).as_u64(),
-                negative: false,
-            }
-        } else {
-            TimeDelta {
-                delta_abs_seconds: (t2 - t1).as_u64(),
-                negative: true,
-            }
-        }
-    }
-}
-
-impl std::fmt::Display for TimeDelta {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        if self.negative {
-            write!(f, "-{}", self.delta_abs_seconds)
-        } else {
-            write!(f, "{}", self.delta_abs_seconds)
-        }
-    }
-}

src/notification_manager/mod.rs

@@ -1,7 +1,8 @@
-pub mod mute_manager;
+pub mod nostr_network_helper;
 mod nostr_event_extensions;
+mod nostr_event_cache;
 pub mod notification_manager;
 
-pub use mute_manager::MuteManager;
+pub use nostr_network_helper::NostrNetworkHelper;
 use nostr_event_extensions::{ExtendedEvent, SqlStringConvertible};
 pub use notification_manager::NotificationManager;

src/notification_manager/mute_manager.rs

@@ -1,128 +0,0 @@
-use super::ExtendedEvent;
-use nostr_sdk::prelude::*;
-use tokio::time::{timeout, Duration};
-
-pub struct MuteManager {
-    client: Client,
-}
-
-impl MuteManager {
-    pub async fn new(relay_url: String) -> Result<Self, Box<dyn std::error::Error>> {
-        let client = Client::new(&Keys::generate());
-        client.add_relay(relay_url.clone()).await?;
-        client.connect().await;
-        Ok(MuteManager { client })
-    }
-
-    pub async fn should_mute_notification_for_pubkey(
-        &self,
-        event: &Event,
-        pubkey: &PublicKey,
-    ) -> bool {
-        log::debug!(
-            "Checking if event {:?} should be muted for pubkey {:?}",
-            event,
-            pubkey
-        );
-        if let Some(mute_list) = self.get_public_mute_list(pubkey).await {
-            for tag in mute_list.tags() {
-                match tag.kind() {
-                    TagKind::SingleLetter(SingleLetterTag {
-                        character: Alphabet::P,
-                        uppercase: false,
-                    }) => {
-                        let tagged_pubkey: Option<PublicKey> =
-                            tag.content().and_then(|h| PublicKey::from_hex(h).ok());
-                        if let Some(tagged_pubkey) = tagged_pubkey {
-                            if event.pubkey == tagged_pubkey {
-                                return true;
-                            }
-                        }
-                    }
-                    TagKind::SingleLetter(SingleLetterTag {
-                        character: Alphabet::E,
-                        uppercase: false,
-                    }) => {
-                        let tagged_event_id: Option<EventId> =
-                            tag.content().and_then(|h| EventId::from_hex(h).ok());
-                        if let Some(tagged_event_id) = tagged_event_id {
-                            if event.id == tagged_event_id
-                                || event.referenced_event_ids().contains(&tagged_event_id)
-                            {
-                                return true;
-                            }
-                        }
-                    }
-                    TagKind::SingleLetter(SingleLetterTag {
-                        character: Alphabet::T,
-                        uppercase: false,
-                    }) => {
-                        let tagged_hashtag: Option<String> = tag.content().map(|h| h.to_string());
-                        if let Some(tagged_hashtag) = tagged_hashtag {
-                            let tags_content =
-                                event.get_tags_content(TagKind::SingleLetter(SingleLetterTag {
-                                    character: Alphabet::T,
-                                    uppercase: false,
-                                }));
-                            let should_mute = tags_content.iter().any(|t| t == &tagged_hashtag);
-                            return should_mute;
-                        }
-                    }
-                    TagKind::Word => {
-                        let tagged_word: Option<String> = tag.content().map(|h| h.to_string());
-                        if let Some(tagged_word) = tagged_word {
-                            if event
-                                .content
-                                .to_lowercase()
-                                .contains(&tagged_word.to_lowercase())
-                            {
-                                return true;
-                            }
-                        }
-                    }
-                    _ => {}
-                }
-            }
-        }
-        false
-    }
-
-    pub async fn get_public_mute_list(&self, pubkey: &PublicKey) -> Option<Event> {
-        let subscription_filter = Filter::new()
-            .kinds(vec![Kind::MuteList])
-            .authors(vec![pubkey.clone()])
-            .limit(1);
-
-        let this_subscription_id = self
-            .client
-            .subscribe(Vec::from([subscription_filter]), None)
-            .await;
-
-        let mut mute_list: Option<Event> = None;
-        let mut notifications = self.client.notifications();
-
-        let timeout_duration = Duration::from_secs(10);
-        while let Ok(result) = timeout(timeout_duration, notifications.recv()).await {
-            if let Ok(notification) = result {
-                if let RelayPoolNotification::Event {
-                    subscription_id,
-                    event,
-                    ..
-                } = notification
-                {
-                    if this_subscription_id == subscription_id && event.kind == Kind::MuteList {
-                        mute_list = Some((*event).clone());
-                        break;
-                    }
-                }
-            }
-        }
-        
-        if mute_list.is_none() {
-            log::debug!("Mute list not found for pubkey {:?}", pubkey);
-        }
-
-        self.client.unsubscribe(this_subscription_id).await;
-        mute_list
-    }
-}

src/notification_manager/nostr_event_cache.rs

@@ -0,0 +1,144 @@
+use crate::utils::time_delta::TimeDelta;
+use tokio::time::Duration;
+use nostr_sdk::prelude::*;
+use std::collections::HashMap;
+use std::sync::Arc;
+use log;
+
+use super::nostr_event_extensions::MaybeConvertibleToMuteList;
+
+struct CacheEntry {
+    event: Option<Event>,   // `None` means the event does not exist as far as we know (It does NOT mean expired)
+    added_at: nostr::Timestamp,
+}
+
+impl CacheEntry {
+    fn is_expired(&self, max_age: Duration) -> bool {
+        let time_delta = TimeDelta::subtracting(nostr::Timestamp::now(), self.added_at);
+        time_delta.negative || (time_delta.delta_abs_seconds > max_age.as_secs())
+    }
+}
+
+pub struct Cache {
+    entries: HashMap<EventId, Arc<CacheEntry>>,
+    mute_lists: HashMap<PublicKey, Arc<CacheEntry>>,
+    contact_lists: HashMap<PublicKey, Arc<CacheEntry>>,
+    max_age: Duration,
+}
+
+impl Cache {
+    // MARK: - Initialization
+
+    pub fn new(max_age: Duration) -> Self {
+        Cache {
+            entries: HashMap::new(),
+            mute_lists: HashMap::new(),
+            contact_lists: HashMap::new(),
+            max_age,
+        }
+    }
+
+    // MARK: - Adding items to the cache
+    
+    pub fn add_optional_mute_list_with_author(&mut self, author: &PublicKey, mute_list: Option<Event>) {
+        if let Some(mute_list) = mute_list {
+            self.add_event(mute_list);
+        } else {
+            self.mute_lists.insert(
+                author.clone(),
+                Arc::new(CacheEntry {
+                    event: None,
+                    added_at: nostr::Timestamp::now(),
+                }),
+            );
+        }
+    }
+    
+    pub fn add_optional_contact_list_with_author(&mut self, author: &PublicKey, contact_list: Option<Event>) {
+        if let Some(contact_list) = contact_list {
+            self.add_event(contact_list);
+        } else {
+            self.contact_lists.insert(
+                author.clone(),
+                Arc::new(CacheEntry {
+                    event: None,
+                    added_at: nostr::Timestamp::now(),
+                }),
+            );
+        }
+    }
+
+    pub fn add_event(&mut self, event: Event) {
+        let entry = Arc::new(CacheEntry {
+            event: Some(event.clone()),
+            added_at: nostr::Timestamp::now(),
+        });
+        self.entries.insert(event.id.clone(), entry.clone());
+
+        match event.kind {
+            Kind::MuteList => {
+                self.mute_lists.insert(event.pubkey.clone(), entry.clone());
+                log::debug!("Added mute list to the cache. Event ID: {}", event.id.to_hex());
+            }
+            Kind::ContactList => {
+                self.contact_lists
+                    .insert(event.pubkey.clone(), entry.clone());
+                log::debug!("Added contact list to the cache. Event ID: {}", event.id.to_hex());
+            }
+            _ => {
+                log::debug!("Added event to the cache. Event ID: {}", event.id.to_hex());
+            }
+        }
+    }
+
+    // MARK: - Fetching items from the cache
+
+    pub fn get_mute_list(&mut self, pubkey: &PublicKey) -> Result<Option<MuteList>, CacheError> {
+        if let Some(entry) = self.mute_lists.get(pubkey) {
+            let entry = entry.clone();  // Clone the Arc to avoid borrowing issues
+            if !entry.is_expired(self.max_age) {
+                if let Some(event) = entry.event.clone() {
+                    return Ok(event.to_mute_list());
+                }
+            } else {
+                log::debug!("Mute list for pubkey {} is expired, removing it from the cache", pubkey.to_hex());
+                self.mute_lists.remove(pubkey);
+                self.remove_event_from_all_maps(&entry.event);
+            }
+        }
+        Err(CacheError::NotFound)
+    }
+
+    pub fn get_contact_list(&mut self, pubkey: &PublicKey) -> Result<Option<Event>, CacheError> {
+        if let Some(entry) = self.contact_lists.get(pubkey) {
+            let entry = entry.clone();  // Clone the Arc to avoid borrowing issues
+            if !entry.is_expired(self.max_age) {
+                return Ok(entry.event.clone());
+            } else {
+                log::debug!("Contact list for pubkey {} is expired, removing it from the cache", pubkey.to_hex());
+                self.contact_lists.remove(pubkey);
+                self.remove_event_from_all_maps(&entry.event);
+            }
+        }
+        Err(CacheError::NotFound)
+    }
+
+    // MARK: - Removing items from the cache
+
+    fn remove_event_from_all_maps(&mut self, event: &Option<Event>) {
+        if let Some(event) = event {
+            let event_id = event.id.clone();
+            let pubkey = event.pubkey.clone();
+            self.entries.remove(&event_id);
+            self.mute_lists.remove(&pubkey);
+            self.contact_lists.remove(&pubkey);
+        }
+        // We can't remove an event from all maps if the event does not exist
+    }
+}
+
+// Error type
+#[derive(Debug)]
+pub enum CacheError {
+    NotFound,
+}

src/notification_manager/nostr_event_extensions.rs

@@ -1,4 +1,5 @@
-use nostr::{self, key::PublicKey, Alphabet, SingleLetterTag, TagKind::SingleLetter};
+use nostr::{self, key::PublicKey, nips::nip51::MuteList, Alphabet, SingleLetterTag, TagKind::SingleLetter};
+use nostr_sdk::{Kind, TagKind};
 
 /// Temporary scaffolding of old methods that have not been ported to use native Event methods
 pub trait ExtendedEvent {
@@ -13,6 +14,9 @@ pub trait ExtendedEvent {
 
     /// Retrieves a set of event IDs referenced by the note
     fn referenced_event_ids(&self) -> std::collections::HashSet<nostr::EventId>;
+    
+    /// Retrieves a set of hashtags (t tags) referenced by the note
+    fn referenced_hashtags(&self) -> std::collections::HashSet<String>;
 }
 
 // This is a wrapper around the Event type from strfry-policies, which adds some useful methods
@@ -44,6 +48,14 @@ impl ExtendedEvent for nostr::Event {
             .filter_map(|tag| nostr::EventId::from_hex(tag).ok())
             .collect()
     }
+    
+    /// Retrieves a set of hashtags (t tags) referenced by the note
+    fn referenced_hashtags(&self) -> std::collections::HashSet<String> {
+        self.get_tags_content(SingleLetter(SingleLetterTag::lowercase(Alphabet::T)))
+            .iter()
+            .map(|tag| tag.to_string())
+            .collect()
+    }
 }
 
 // MARK: - SQL String Convertible
@@ -85,3 +97,21 @@ impl SqlStringConvertible for nostr::Timestamp {
         Ok(nostr::Timestamp::from(u64_timestamp))
     }
 }
+
+pub trait MaybeConvertibleToMuteList {
+    fn to_mute_list(&self) -> Option<MuteList>;
+}
+
+impl MaybeConvertibleToMuteList for nostr::Event {
+    fn to_mute_list(&self) -> Option<MuteList> {
+        if self.kind != Kind::MuteList {
+            return None;
+        }
+        Some(MuteList { 
+            public_keys: self.referenced_pubkeys().iter().map(|pk| pk.clone()).collect(),
+            hashtags: self.referenced_hashtags().iter().map(|tag| tag.clone()).collect(),
+            event_ids: self.referenced_event_ids().iter().map(|id| id.clone()).collect(),
+            words: self.get_tags_content(TagKind::Word).iter().map(|tag| tag.to_string()).collect(),
+        })
+    }
+}

src/notification_manager/nostr_network_helper.rs

@@ -0,0 +1,161 @@
+use tokio::sync::Mutex;
+use super::nostr_event_extensions::MaybeConvertibleToMuteList;
+use super::ExtendedEvent;
+use nostr_sdk::prelude::*;
+use super::nostr_event_cache::Cache;
+use tokio::time::{timeout, Duration};
+
+const NOTE_FETCH_TIMEOUT: Duration = Duration::from_secs(5);
+const CACHE_MAX_AGE: Duration = Duration::from_secs(60);
+
+pub struct NostrNetworkHelper {
+    client: Client,
+    cache: Mutex<Cache>,
+}
+
+impl NostrNetworkHelper {
+    // MARK: - Initialization
+
+    pub async fn new(relay_url: String) -> Result<Self, Box<dyn std::error::Error>> {
+        let client = Client::new(&Keys::generate());
+        client.add_relay(relay_url.clone()).await?;
+        client.connect().await;
+        
+        Ok(NostrNetworkHelper { client, cache: Mutex::new(Cache::new(CACHE_MAX_AGE)) })
+    }
+
+    // MARK: - Answering questions about a user
+
+    pub async fn should_mute_notification_for_pubkey(
+        &self,
+        event: &Event,
+        pubkey: &PublicKey,
+    ) -> bool {
+        log::debug!(
+            "Checking if event {:?} should be muted for pubkey {:?}",
+            event,
+            pubkey
+        );
+        if let Some(mute_list) = self.get_public_mute_list(pubkey).await {
+            for muted_public_key in mute_list.public_keys {
+                if event.pubkey == muted_public_key {
+                    return true;
+                }
+            }
+            for muted_event_id in mute_list.event_ids {
+                if event.id == muted_event_id
+                    || event.referenced_event_ids().contains(&muted_event_id)
+                {
+                    return true;
+                }
+            }
+            for muted_hashtag in mute_list.hashtags {
+                if event
+                    .referenced_hashtags()
+                    .iter()
+                    .any(|t| t == &muted_hashtag)
+                {
+                    return true;
+                }
+            }
+            for muted_word in mute_list.words {
+                if event
+                    .content
+                    .to_lowercase()
+                    .contains(&muted_word.to_lowercase())
+                {
+                    return true;
+                }
+            }
+        }
+        false
+    }
+
+    pub async fn does_pubkey_follow_pubkey(
+        &self,
+        source_pubkey: &PublicKey,
+        target_pubkey: &PublicKey,
+    ) -> bool {
+        log::debug!(
+            "Checking if pubkey {:?} follows pubkey {:?}",
+            source_pubkey,
+            target_pubkey
+        );
+        if let Some(contact_list) = self.get_contact_list(source_pubkey).await {
+            return contact_list.referenced_pubkeys().contains(target_pubkey);
+        }
+        false
+    }
+
+    // MARK: - Getting specific event types with caching
+
+    pub async fn get_public_mute_list(&self, pubkey: &PublicKey) -> Option<MuteList> {
+        {
+            let mut cache_mutex_guard = self.cache.lock().await;
+            if let Ok(optional_mute_list) = cache_mutex_guard.get_mute_list(pubkey) {
+                return optional_mute_list;
+            }
+        }   // Release the lock here for improved performance
+        
+        // We don't have an answer from the cache, so we need to fetch it
+        let mute_list_event = self.fetch_single_event(pubkey, Kind::MuteList).await;
+        let mut cache_mutex_guard = self.cache.lock().await;
+        cache_mutex_guard.add_optional_mute_list_with_author(pubkey, mute_list_event.clone());
+        mute_list_event?.to_mute_list()
+    }
+
+    pub async fn get_contact_list(&self, pubkey: &PublicKey) -> Option<Event> {
+        {
+            let mut cache_mutex_guard = self.cache.lock().await;
+            if let Ok(optional_contact_list) = cache_mutex_guard.get_contact_list(pubkey) {
+                return optional_contact_list;
+            }
+        }   // Release the lock here for improved performance
+        
+        // We don't have an answer from the cache, so we need to fetch it
+        let contact_list_event = self.fetch_single_event(pubkey, Kind::ContactList).await;
+        let mut cache_mutex_guard = self.cache.lock().await;
+        cache_mutex_guard.add_optional_contact_list_with_author(pubkey, contact_list_event.clone());
+        contact_list_event
+    }
+
+    // MARK: - Lower level fetching functions
+
+    async fn fetch_single_event(&self, author: &PublicKey, kind: Kind) -> Option<Event> {
+        let subscription_filter = Filter::new()
+            .kinds(vec![kind])
+            .authors(vec![author.clone()])
+            .limit(1);
+        
+        let mut notifications = self.client.notifications();
+        let this_subscription_id = self
+            .client
+            .subscribe(Vec::from([subscription_filter]), None)
+            .await;
+
+        let mut event: Option<Event> = None;
+        
+        while let Ok(result) = timeout(NOTE_FETCH_TIMEOUT, notifications.recv()).await {
+            if let Ok(notification) = result {
+                if let RelayPoolNotification::Event {
+                    subscription_id,
+                    event: event_option,
+                    ..
+                } = notification
+                {
+                    if this_subscription_id == subscription_id && event_option.kind == kind {
+                        event = Some((*event_option).clone());
+                        break;
+                    }
+                }
+            }
+        }
+
+        if event.is_none() {
+            log::info!("Event of kind {:?} not found for pubkey {:?}", kind, author);
+        }
+
+        self.client.unsubscribe(this_subscription_id).await;
+        event
+    }
+}

src/notification_manager/notification_manager.rs

@@ -4,13 +4,16 @@ use nostr::event::EventId;
 use nostr::key::PublicKey;
 use nostr::types::Timestamp;
 use nostr_sdk::JsonUtil;
+use nostr_sdk::Kind;
 use rusqlite;
 use rusqlite::params;
+use serde::Deserialize;
+use serde::Serialize;
 use tokio::sync::Mutex;
 use std::collections::HashSet;
 use tokio;
 
-use super::mute_manager::MuteManager;
+use super::nostr_network_helper::NostrNetworkHelper;
 use super::ExtendedEvent;
 use super::SqlStringConvertible;
 use nostr::Event;
@@ -24,8 +27,7 @@ pub struct NotificationManager {
     db: Mutex<r2d2::Pool<SqliteConnectionManager>>,
     apns_topic: String,
     apns_client: Mutex<Client>,
-
+    nostr_network_helper: NostrNetworkHelper,
-    mute_manager: Mutex<MuteManager>,
 }
 
 impl NotificationManager {
@@ -40,8 +42,6 @@ impl NotificationManager {
         apns_environment: a2::client::Endpoint,
         apns_topic: String,
     ) -> Result<Self, Box<dyn std::error::Error>> {
-        let mute_manager = MuteManager::new(relay_url.clone()).await?;
-
         let connection = db.get()?;
         Self::setup_database(&connection)?;
 
@@ -58,13 +58,15 @@ impl NotificationManager {
             apns_topic,
             apns_client: Mutex::new(client),
             db: Mutex::new(db),
-            mute_manager: Mutex::new(mute_manager),
+            nostr_network_helper: NostrNetworkHelper::new(relay_url.clone()).await?,
         })
     }
 
     // MARK: - Database setup operations
 
     pub fn setup_database(db: &rusqlite::Connection) -> Result<(), rusqlite::Error> {
+        // Initial schema setup
+        
         db.execute(
             "CREATE TABLE IF NOT EXISTS notifications (
                 id TEXT PRIMARY KEY,
@@ -94,8 +96,17 @@ impl NotificationManager {
             [],
         )?;
 
-        Self::add_column_if_not_exists(&db, "notifications", "sent_at", "INTEGER")?;
+        Self::add_column_if_not_exists(&db, "notifications", "sent_at", "INTEGER", None)?;
-        Self::add_column_if_not_exists(&db, "user_info", "added_at", "INTEGER")?;
+        Self::add_column_if_not_exists(&db, "user_info", "added_at", "INTEGER", None)?;
+        
+        // Notification settings migration (https://github.com/damus-io/damus/issues/2360)
+        
+        Self::add_column_if_not_exists(&db, "user_info", "zap_notifications_enabled", "BOOLEAN", Some("true"))?;
+        Self::add_column_if_not_exists(&db, "user_info", "mention_notifications_enabled", "BOOLEAN", Some("true"))?;
+        Self::add_column_if_not_exists(&db, "user_info", "repost_notifications_enabled", "BOOLEAN", Some("true"))?;
+        Self::add_column_if_not_exists(&db, "user_info", "reaction_notifications_enabled", "BOOLEAN", Some("true"))?;
+        Self::add_column_if_not_exists(&db, "user_info", "dm_notifications_enabled", "BOOLEAN", Some("true"))?;
+        Self::add_column_if_not_exists(&db, "user_info", "only_notifications_from_following_enabled", "BOOLEAN", Some("false"))?;
 
         Ok(())
     }
@@ -105,6 +116,7 @@ impl NotificationManager {
         table_name: &str,
         column_name: &str,
         column_type: &str,
+        default_value: Option<&str>,
     ) -> Result<(), rusqlite::Error> {
         let query = format!("PRAGMA table_info({})", table_name);
         let mut stmt = db.prepare(&query)?;
@@ -115,8 +127,11 @@ impl NotificationManager {
 
         if !column_names.contains(&column_name.to_string()) {
             let query = format!(
-                "ALTER TABLE {} ADD COLUMN {} {}",
+                "ALTER TABLE {} ADD COLUMN {} {} {}",
-                table_name, column_name, column_type
+                table_name, column_name, column_type, match default_value {
+                    Some(value) => format!("DEFAULT {}", value),
+                    None => "".to_string(),
+                },
             );
             db.execute(&query, [])?;
         }
@@ -203,8 +218,7 @@ impl NotificationManager {
         let mut pubkeys_to_notify = HashSet::new();
         for pubkey in relevant_pubkeys_yet_to_receive {
             let should_mute: bool = {
-                let mute_manager_mutex_guard = self.mute_manager.lock().await;
+                self.nostr_network_helper
-                mute_manager_mutex_guard
                     .should_mute_notification_for_pubkey(event, &pubkey)
                     .await
             };
@@ -251,12 +265,40 @@ impl NotificationManager {
     ) -> Result<(), Box<dyn std::error::Error>> {
         let user_device_tokens = self.get_user_device_tokens(pubkey).await?;
         for device_token in user_device_tokens {
+            if !self.user_wants_notification(pubkey, device_token.clone(), event).await? {
+                continue;
+            }
             self.send_event_notification_to_device_token(event, &device_token)
                 .await?;
         }
         Ok(())
     }
     
+    async fn user_wants_notification(
+        &self,
+        pubkey: &PublicKey,
+        device_token: String,
+        event: &Event,
+    ) -> Result<bool, Box<dyn std::error::Error>> {
+        let notification_preferences = self.get_user_notification_settings(pubkey, device_token).await?;
+        if notification_preferences.only_notifications_from_following_enabled {
+            if !self.nostr_network_helper.does_pubkey_follow_pubkey(pubkey, &event.author()).await {
+                return Ok(false);
+            }
+        }
+        match event.kind {
+            Kind::TextNote => Ok(notification_preferences.mention_notifications_enabled),   // TODO: Not 100% accurate
+            Kind::EncryptedDirectMessage => Ok(notification_preferences.dm_notifications_enabled),
+            Kind::Repost => Ok(notification_preferences.repost_notifications_enabled),
+            Kind::GenericRepost => Ok(notification_preferences.repost_notifications_enabled),
+            Kind::Reaction => Ok(notification_preferences.reaction_notifications_enabled),
+            Kind::ZapPrivateMessage => Ok(notification_preferences.zap_notifications_enabled),
+            Kind::ZapRequest => Ok(notification_preferences.zap_notifications_enabled),
+            Kind::ZapReceipt => Ok(notification_preferences.zap_notifications_enabled),
+            _ => Ok(false),
+        }
+    }
+
     async fn get_user_device_tokens(
         &self,
         pubkey: &PublicKey,
@@ -344,6 +386,8 @@ impl NotificationManager {
         (title, "".to_string(), body)
     }
     
+    // MARK: - User device info and settings
+
     pub async fn save_user_device_info(
         &self,
         pubkey: nostr::PublicKey,
@@ -375,6 +419,65 @@ impl NotificationManager {
         )?;
         Ok(())
     }
+    
+    pub async fn get_user_notification_settings(
+        &self,
+        pubkey: &PublicKey,
+        device_token: String,
+    ) -> Result<UserNotificationSettings, Box<dyn std::error::Error>> {
+        let db_mutex_guard = self.db.lock().await;
+        let connection = db_mutex_guard.get()?;
+        let mut stmt = connection.prepare(
+            "SELECT zap_notifications_enabled, mention_notifications_enabled, repost_notifications_enabled, reaction_notifications_enabled, dm_notifications_enabled, only_notifications_from_following_enabled FROM user_info WHERE pubkey = ? AND device_token = ?",
+        )?;
+        let settings = stmt
+            .query_row([pubkey.to_sql_string(), device_token], |row| {
+                Ok(UserNotificationSettings {
+                    zap_notifications_enabled: row.get(0)?,
+                    mention_notifications_enabled: row.get(1)?,
+                    repost_notifications_enabled: row.get(2)?,
+                    reaction_notifications_enabled: row.get(3)?,
+                    dm_notifications_enabled: row.get(4)?,
+                    only_notifications_from_following_enabled: row.get(5)?,
+                })
+            })?;
+        
+        Ok(settings)
+    }
+    
+    pub async fn save_user_notification_settings(
+        &self,
+        pubkey: &PublicKey,
+        device_token: String,
+        settings: UserNotificationSettings,
+    ) -> Result<(), Box<dyn std::error::Error>> {
+        let db_mutex_guard = self.db.lock().await;
+        let connection = db_mutex_guard.get()?;
+        connection.execute(
+            "UPDATE user_info SET zap_notifications_enabled = ?, mention_notifications_enabled = ?, repost_notifications_enabled = ?, reaction_notifications_enabled = ?, dm_notifications_enabled = ?, only_notifications_from_following_enabled = ? WHERE pubkey = ? AND device_token = ?",
+            params![
+                settings.zap_notifications_enabled,
+                settings.mention_notifications_enabled,
+                settings.repost_notifications_enabled,
+                settings.reaction_notifications_enabled,
+                settings.dm_notifications_enabled,
+                settings.only_notifications_from_following_enabled,
+                pubkey.to_sql_string(),
+                device_token,
+            ],
+        )?;
+        Ok(())
+    }
+}
+
+#[derive(Serialize, Deserialize, Debug)]
+pub struct UserNotificationSettings {
+    zap_notifications_enabled: bool,
+    mention_notifications_enabled: bool,
+    repost_notifications_enabled: bool,
+    reaction_notifications_enabled: bool,
+    dm_notifications_enabled: bool,
+    only_notifications_from_following_enabled: bool
 }
 
 struct NotificationStatus {

src/utils/mod.rs

@@ -0,0 +1 @@
+pub mod time_delta;

src/utils/time_delta.rs

@@ -0,0 +1,34 @@
+use nostr_sdk::Timestamp;
+
+pub struct TimeDelta {
+    pub delta_abs_seconds: u64,
+    pub negative: bool,
+}
+
+impl TimeDelta {
+    /// Safely calculate the difference between two timestamps in seconds
+    /// This function is safer against overflows than subtracting the timestamps directly
+    pub fn subtracting(t1: Timestamp, t2: Timestamp) -> TimeDelta {
+        if t1 > t2 {
+            TimeDelta {
+                delta_abs_seconds: (t1 - t2).as_u64(),
+                negative: false,
+            }
+        } else {
+            TimeDelta {
+                delta_abs_seconds: (t2 - t1).as_u64(),
+                negative: true,
+            }
+        }
+    }
+}
+
+impl std::fmt::Display for TimeDelta {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        if self.negative {
+            write!(f, "-{}", self.delta_abs_seconds)
+        } else {
+            write!(f, "{}", self.delta_abs_seconds)
+        }
+    }
+}