Merge pull request #377 from RedisLabsModules/add-new-event-notification-flag

Add NEW key space notification flag

Author: iddm

deny.toml

@@ -281,6 +281,10 @@ include-dependencies = true
 name = "redis-module-macros"
 allow-globs = ["*"]
 
+[[bans.build.bypass]]
+name = "redis-module-macros-internals"
+allow-globs = ["*"]
+
 [[bans.build.bypass]]
 name = "libloading"
 allow-globs = ["*"]

examples/events.rs

@@ -5,6 +5,7 @@ use std::ptr::NonNull;
 use std::sync::atomic::{AtomicI64, Ordering};
 
 static NUM_KEY_MISSES: AtomicI64 = AtomicI64::new(0);
+static NUM_KEYS: AtomicI64 = AtomicI64::new(0);
 
 fn on_event(ctx: &Context, event_type: NotifyEvent, event: &str, key: &[u8]) {
     if key == b"num_sets" {
@@ -52,6 +53,13 @@ fn num_key_miss(_ctx: &Context, _args: Vec<RedisString>) -> RedisResult {
     Ok(RedisValue::Integer(NUM_KEY_MISSES.load(Ordering::SeqCst)))
 }
 
+fn on_new_key(_ctx: &Context, _event_type: NotifyEvent, _event: &str, _key: &[u8]) {
+    NUM_KEYS.fetch_add(1, Ordering::SeqCst);
+}
+
+fn num_keys(_ctx: &Context, _args: Vec<RedisString>) -> RedisResult {
+    Ok(RedisValue::Integer(NUM_KEYS.load(Ordering::SeqCst)))
+}
 //////////////////////////////////////////////////////
 
 redis_module! {
@@ -62,10 +70,12 @@ redis_module! {
     commands: [
         ["events.send", event_send, "", 0, 0, 0],
         ["events.num_key_miss", num_key_miss, "", 0, 0, 0],
+        ["events.num_keys", num_keys, "", 0, 0, 0],
     ],
     event_handlers: [
         [@STRING: on_event],
         [@STREAM: on_stream],
         [@MISSED: on_key_miss],
+        [@NEW: on_new_key],
     ],
 }

src/macros.rs

@@ -68,10 +68,19 @@ macro_rules! redis_event_handler {
             $crate::raw::Status::Ok as c_int
         }
 
-        if unsafe {
+        let all_available_notification_flags = $crate::raw::get_keyspace_notification_flags_all();
+        let available_wanted_notification_flags = $event_type.intersection(all_available_notification_flags);
+        if !all_available_notification_flags.contains($event_type) {
+            let not_supported = $event_type.difference(all_available_notification_flags);
+            $crate::Context::new($ctx).log_notice(&format!(
+                "These event notification flags set aren't supported: {not_supported:?}. These flags will be used: {available_wanted_notification_flags:?}"
+            ));
+        }
+
+        if !available_wanted_notification_flags.is_empty() && unsafe {
             $crate::raw::RedisModule_SubscribeToKeyspaceEvents.unwrap()(
                 $ctx,
-                $event_type.bits(),
+                available_wanted_notification_flags.bits(),
                 Some(__handle_event),
             )
         } == $crate::raw::Status::Err as c_int

src/raw.rs

@@ -134,9 +134,16 @@ bitflags! {
         const EXPIRED = REDISMODULE_NOTIFY_EXPIRED;
         const EVICTED = REDISMODULE_NOTIFY_EVICTED;
         const STREAM = REDISMODULE_NOTIFY_STREAM;
+        /// Available only starting from Redis `7.0.1`.
+        const NEW = REDISMODULE_NOTIFY_NEW;
         const MODULE = REDISMODULE_NOTIFY_MODULE;
         const LOADED = REDISMODULE_NOTIFY_LOADED;
         const MISSED = REDISMODULE_NOTIFY_KEY_MISS;
+        /// Does not include the [`Self::MISSED`] and [`Self::NEW`].
+        ///
+        /// Includes [`Self::GENERIC`], [`Self::STRING`], [`Self::LIST`],
+        /// [`Self::SET`], [`Self::HASH`], [`Self::ZSET`], [`Self::EXPIRED`],
+        /// [`Self::EVICTED`], [`Self::STREAM`], [`Self::MODULE`].
         const ALL = REDISMODULE_NOTIFY_ALL;
         const TRIMMED = REDISMODULE_NOTIFY_TRIMMED;
     }
@@ -905,6 +912,24 @@ pub fn get_keyspace_events() -> NotifyEvent {
     }
 }
 
+/// Returns all the available notification flags for key-space
+/// notifications.
+///
+/// # Safety
+///
+/// This function is safe to use as it doesn't perform any work with
+/// the [RedisModuleCtx] pointer except for passing it to the redis server.
+///
+/// # Panics
+///
+/// Panics when the [RedisModule_GetKeyspaceNotificationFlagsAll] is
+/// unavailable.
+pub fn get_keyspace_notification_flags_all() -> NotifyEvent {
+    unsafe {
+        NotifyEvent::from_bits_truncate(RedisModule_GetKeyspaceNotificationFlagsAll.unwrap()())
+    }
+}
+
 #[derive(Debug, PartialEq, Eq, PartialOrd, Ord)]
 pub struct Version {
     pub major: i32,