refactor(events): Allow box dyn for event handler (#2629)

Co-authored-by: Nishant Joshi <nishant.joshi@juspay.in>

crates/router/src/events.rs

@@ -4,7 +4,15 @@ pub mod api_logs;
 pub mod event_logger;
 
 pub trait EventHandler: Sync + Send + dyn_clone::DynClone {
-    fn log_event<T: Event>(&self, event: T);
+    fn log_event(&self, event: RawEvent);
+}
+
+dyn_clone::clone_trait_object!(EventHandler);
+
+pub struct RawEvent {
+    event_type: EventType,
+    key: String,
+    payload: serde_json::Value,
 }
 
 #[derive(Debug, Serialize)]
@@ -15,12 +23,3 @@ pub enum EventType {
     Refund,
     ApiLogs,
 }
-
-pub trait Event
-where
-    Self: Serialize,
-{
-    fn event_type() -> EventType;
-
-    fn key(&self) -> String;
-}

crates/router/src/events/api_logs.rs

@@ -2,7 +2,7 @@ use router_env::{tracing_actix_web::RequestId, types::FlowMetric};
 use serde::{Deserialize, Serialize};
 use time::OffsetDateTime;
 
-use super::Event;
+use super::{EventType, RawEvent};
 
 #[derive(Clone, Debug, Eq, PartialEq, Serialize, Deserialize)]
 pub struct ApiEvent {
@@ -30,12 +30,14 @@ impl ApiEvent {
     }
 }
 
-impl Event for ApiEvent {
-    fn event_type() -> super::EventType {
-        super::EventType::ApiLogs
-    }
+impl TryFrom<ApiEvent> for RawEvent {
+    type Error = serde_json::Error;
 
-    fn key(&self) -> String {
-        self.request_id.to_string()
+    fn try_from(value: ApiEvent) -> Result<Self, Self::Error> {
+        Ok(Self {
+            event_type: EventType::ApiLogs,
+            key: value.request_id.clone(),
+            payload: serde_json::to_value(value)?,
+        })
     }
 }

crates/router/src/events/event_logger.rs

@@ -1,11 +1,11 @@
-use super::{Event, EventHandler};
+use super::{EventHandler, RawEvent};
 use crate::services::logger;
 
 #[derive(Clone, Debug, Default)]
 pub struct EventLogger {}
 
 impl EventHandler for EventLogger {
-    fn log_event<T: Event>(&self, event: T) {
-        logger::info!(current = ?serde_json::to_string(&event).unwrap_or(r#"{ "error": "Serialization failed" }"#.to_string()), event_type =? T::event_type(), event_id =? event.key(), log_type = "event");
+    fn log_event(&self, event: RawEvent) {
+        logger::info!(event = ?serde_json::to_string(&event.payload).unwrap_or(r#"{ "error": "Serialization failed" }"#.to_string()), event_type =? event.event_type, event_id =? event.key, log_type = "event");
     }
 }

crates/router/src/routes/app.rs

@@ -32,11 +32,11 @@ use crate::{
 };
 
 #[derive(Clone)]
-pub struct AppStateBase<E: EventHandler> {
+pub struct AppState {
     pub flow_name: String,
     pub store: Box<dyn StorageInterface>,
     pub conf: Arc<settings::Settings>,
-    pub event_handler: E,
+    pub event_handler: Box<dyn EventHandler>,
     #[cfg(feature = "email")]
     pub email_client: Arc<dyn EmailClient>,
     #[cfg(feature = "kms")]
@@ -44,8 +44,6 @@ pub struct AppStateBase<E: EventHandler> {
     pub api_client: Box<dyn crate::services::ApiClient>,
 }
 
-pub type AppState = AppStateBase<EventLogger>;
-
 impl scheduler::SchedulerAppState for AppState {
     fn get_db(&self) -> Box<dyn SchedulerInterface> {
         self.store.get_scheduler_db()
@@ -53,10 +51,9 @@ impl scheduler::SchedulerAppState for AppState {
 }
 
 pub trait AppStateInfo {
-    type Event: EventHandler;
     fn conf(&self) -> settings::Settings;
     fn store(&self) -> Box<dyn StorageInterface>;
-    fn event_handler(&self) -> &Self::Event;
+    fn event_handler(&self) -> Box<dyn EventHandler>;
     #[cfg(feature = "email")]
     fn email_client(&self) -> Arc<dyn EmailClient>;
     fn add_request_id(&mut self, request_id: RequestId);
@@ -66,7 +63,6 @@ pub trait AppStateInfo {
 }
 
 impl AppStateInfo for AppState {
-    type Event = EventLogger;
     fn conf(&self) -> settings::Settings {
         self.conf.as_ref().to_owned()
     }
@@ -77,8 +73,8 @@ impl AppStateInfo for AppState {
     fn email_client(&self) -> Arc<dyn EmailClient> {
         self.email_client.to_owned()
     }
-    fn event_handler(&self) -> &Self::Event {
-        &self.event_handler
+    fn event_handler(&self) -> Box<dyn EventHandler> {
+        self.event_handler.to_owned()
     }
     fn add_request_id(&mut self, request_id: RequestId) {
         self.api_client.add_request_id(request_id);
@@ -148,7 +144,7 @@ impl AppState {
             #[cfg(feature = "kms")]
             kms_secrets: Arc::new(kms_secrets),
             api_client,
-            event_handler: EventLogger::default(),
+            event_handler: Box::<EventLogger>::default(),
         }
     }
 

crates/router/src/services/api.rs

@@ -25,6 +25,7 @@ use serde_json::json;
 use tera::{Context, Tera};
 
 use self::request::{HeaderExt, RequestBuilderExt};
+use super::authentication::{AuthInfo, AuthenticateAndFetch};
 use crate::{
     configs::settings::{Connectors, Settings},
     consts,
@@ -33,14 +34,13 @@ use crate::{
         errors::{self, CustomResult},
         payments,
     },
-    events::{api_logs::ApiEvent, EventHandler},
+    events::api_logs::ApiEvent,
     logger,
     routes::{
         app::AppStateInfo,
         metrics::{self, request as metrics_request},
         AppState,
     },
-    services::authentication as auth,
     types::{
         self,
         api::{self, ConnectorCommon},
@@ -751,7 +751,7 @@ pub async fn server_wrap_util<'a, 'b, A, U, T, Q, F, Fut, E, OErr>(
     request: &'a HttpRequest,
     payload: T,
     func: F,
-    api_auth: &dyn auth::AuthenticateAndFetch<U, A>,
+    api_auth: &dyn AuthenticateAndFetch<U, A>,
     lock_action: api_locking::LockAction,
 ) -> CustomResult<ApplicationResponse<Q>, OErr>
 where
@@ -761,7 +761,7 @@ where
     Q: Serialize + Debug + 'a,
     T: Debug,
     A: AppStateInfo + Clone,
-    U: auth::AuthInfo,
+    U: AuthInfo,
     E: ErrorSwitch<OErr> + error_stack::Context,
     OErr: ResponseError + error_stack::Context,
     errors::ApiErrorResponse: ErrorSwitch<OErr>,
@@ -816,12 +816,15 @@ where
         Ok(res) => metrics::request::track_response_status_code(res),
         Err(err) => err.current_context().status_code().as_u16().into(),
     };
-    state.event_handler().log_event(ApiEvent::new(
-        flow,
-        &request_id,
-        request_duration,
-        status_code,
-    ));
+    let api_event = ApiEvent::new(flow, &request_id, request_duration, status_code);
+    match api_event.clone().try_into() {
+        Ok(event) => {
+            state.event_handler().log_event(event);
+        }
+        Err(err) => {
+            logger::error!(error=?err, event=?api_event, "Error Logging API Event");
+        }
+    }
 
     metrics::request::status_code_metrics(status_code, flow.to_string(), merchant_id.to_string());
 
@@ -838,7 +841,7 @@ pub async fn server_wrap<'a, A, T, U, Q, F, Fut, E>(
     request: &'a HttpRequest,
     payload: T,
     func: F,
-    api_auth: &dyn auth::AuthenticateAndFetch<U, A>,
+    api_auth: &dyn AuthenticateAndFetch<U, A>,
     lock_action: api_locking::LockAction,
 ) -> HttpResponse
 where
@@ -846,7 +849,7 @@ where
     Fut: Future<Output = CustomResult<ApplicationResponse<Q>, E>>,
     Q: Serialize + Debug + 'a,
     T: Debug,
-    U: auth::AuthInfo,
+    U: AuthInfo,
     A: AppStateInfo + Clone,
     ApplicationResponse<Q>: Debug,
     E: ErrorSwitch<api_models::errors::types::ApiErrorResponse> + error_stack::Context,