feat: add deep health check (#3210)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>

crates/api_models/src/health_check.rs

@@ -0,0 +1,6 @@
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+pub struct RouterHealthCheckResponse {
+    pub database: String,
+    pub redis: String,
+    pub locker: String,
+}

crates/api_models/src/lib.rs

@@ -16,6 +16,7 @@ pub mod errors;
 pub mod events;
 pub mod files;
 pub mod gsm;
+pub mod health_check;
 pub mod locker_migration;
 pub mod mandates;
 pub mod organization;

crates/router/src/consts.rs

@@ -70,3 +70,5 @@ pub const EMAIL_TOKEN_TIME_IN_SECS: u64 = 60 * 60 * 24; // 1 day
 pub const VERIFY_CONNECTOR_ID_PREFIX: &str = "conn_verify";
 #[cfg(feature = "olap")]
 pub const VERIFY_CONNECTOR_MERCHANT_ID: &str = "test_merchant";
+
+pub const LOCKER_HEALTH_CALL_PATH: &str = "/health";

crates/router/src/db.rs

@@ -14,6 +14,7 @@ pub mod events;
 pub mod file;
 pub mod fraud_check;
 pub mod gsm;
+pub mod health_check;
 mod kafka_store;
 pub mod locker_mock_up;
 pub mod mandate;
@@ -103,6 +104,7 @@ pub trait StorageInterface:
     + user_role::UserRoleInterface
     + authorization::AuthorizationInterface
     + user::sample_data::BatchSampleDataInterface
+    + health_check::HealthCheckInterface
     + 'static
 {
     fn get_scheduler_db(&self) -> Box<dyn scheduler::SchedulerInterface>;

crates/router/src/db/health_check.rs

@@ -0,0 +1,147 @@
+use async_bb8_diesel::{AsyncConnection, AsyncRunQueryDsl};
+use diesel_models::ConfigNew;
+use error_stack::ResultExt;
+use router_env::logger;
+
+use super::{MockDb, StorageInterface, Store};
+use crate::{
+    connection,
+    consts::LOCKER_HEALTH_CALL_PATH,
+    core::errors::{self, CustomResult},
+    routes,
+    services::api as services,
+    types::storage,
+};
+
+#[async_trait::async_trait]
+pub trait HealthCheckInterface {
+    async fn health_check_db(&self) -> CustomResult<(), errors::HealthCheckDBError>;
+    async fn health_check_redis(
+        &self,
+        db: &dyn StorageInterface,
+    ) -> CustomResult<(), errors::HealthCheckRedisError>;
+    async fn health_check_locker(
+        &self,
+        state: &routes::AppState,
+    ) -> CustomResult<(), errors::HealthCheckLockerError>;
+}
+
+#[async_trait::async_trait]
+impl HealthCheckInterface for Store {
+    async fn health_check_db(&self) -> CustomResult<(), errors::HealthCheckDBError> {
+        let conn = connection::pg_connection_write(self)
+            .await
+            .change_context(errors::HealthCheckDBError::DBError)?;
+
+        let _data = conn
+            .transaction_async(|conn| {
+                Box::pin(async move {
+                    let query =
+                        diesel::select(diesel::dsl::sql::<diesel::sql_types::Integer>("1 + 1"));
+                    let _x: i32 = query.get_result_async(&conn).await.map_err(|err| {
+                        logger::error!(read_err=?err,"Error while reading element in the database");
+                        errors::HealthCheckDBError::DBReadError
+                    })?;
+
+                    logger::debug!("Database read was successful");
+
+                    let config = ConfigNew {
+                        key: "test_key".to_string(),
+                        config: "test_value".to_string(),
+                    };
+
+                    config.insert(&conn).await.map_err(|err| {
+                        logger::error!(write_err=?err,"Error while writing to database");
+                        errors::HealthCheckDBError::DBWriteError
+                    })?;
+
+                    logger::debug!("Database write was successful");
+
+                    storage::Config::delete_by_key(&conn, "test_key").await.map_err(|err| {
+                        logger::error!(delete_err=?err,"Error while deleting element in the database");
+                        errors::HealthCheckDBError::DBDeleteError
+                    })?;
+
+                    logger::debug!("Database delete was successful");
+
+                    Ok::<_, errors::HealthCheckDBError>(())
+                })
+            })
+            .await?;
+
+        Ok(())
+    }
+
+    async fn health_check_redis(
+        &self,
+        db: &dyn StorageInterface,
+    ) -> CustomResult<(), errors::HealthCheckRedisError> {
+        let redis_conn = db
+            .get_redis_conn()
+            .change_context(errors::HealthCheckRedisError::RedisConnectionError)?;
+
+        redis_conn
+            .serialize_and_set_key_with_expiry("test_key", "test_value", 30)
+            .await
+            .change_context(errors::HealthCheckRedisError::SetFailed)?;
+
+        logger::debug!("Redis set_key was successful");
+
+        redis_conn
+            .get_key("test_key")
+            .await
+            .change_context(errors::HealthCheckRedisError::GetFailed)?;
+
+        logger::debug!("Redis get_key was successful");
+
+        redis_conn
+            .delete_key("test_key")
+            .await
+            .change_context(errors::HealthCheckRedisError::DeleteFailed)?;
+
+        logger::debug!("Redis delete_key was successful");
+
+        Ok(())
+    }
+
+    async fn health_check_locker(
+        &self,
+        state: &routes::AppState,
+    ) -> CustomResult<(), errors::HealthCheckLockerError> {
+        let locker = &state.conf.locker;
+        if !locker.mock_locker {
+            let mut url = locker.host_rs.to_owned();
+            url.push_str(LOCKER_HEALTH_CALL_PATH);
+            let request = services::Request::new(services::Method::Get, &url);
+            services::call_connector_api(state, request)
+                .await
+                .change_context(errors::HealthCheckLockerError::FailedToCallLocker)?
+                .ok();
+        }
+
+        logger::debug!("Locker call was successful");
+
+        Ok(())
+    }
+}
+
+#[async_trait::async_trait]
+impl HealthCheckInterface for MockDb {
+    async fn health_check_db(&self) -> CustomResult<(), errors::HealthCheckDBError> {
+        Ok(())
+    }
+
+    async fn health_check_redis(
+        &self,
+        _: &dyn StorageInterface,
+    ) -> CustomResult<(), errors::HealthCheckRedisError> {
+        Ok(())
+    }
+
+    async fn health_check_locker(
+        &self,
+        _: &routes::AppState,
+    ) -> CustomResult<(), errors::HealthCheckLockerError> {
+        Ok(())
+    }
+}

crates/router/src/db/kafka_store.rs

@@ -43,6 +43,7 @@ use crate::{
         events::EventInterface,
         file::FileMetadataInterface,
         gsm::GsmInterface,
+        health_check::HealthCheckInterface,
         locker_mock_up::LockerMockUpInterface,
         mandate::MandateInterface,
         merchant_account::MerchantAccountInterface,
@@ -57,6 +58,7 @@ use crate::{
         routing_algorithm::RoutingAlgorithmInterface,
         MasterKeyInterface, StorageInterface,
     },
+    routes,
     services::{authentication, kafka::KafkaProducer, Store},
     types::{
         domain,
@@ -2131,3 +2133,24 @@ impl AuthorizationInterface for KafkaStore {
             .await
     }
 }
+
+#[async_trait::async_trait]
+impl HealthCheckInterface for KafkaStore {
+    async fn health_check_db(&self) -> CustomResult<(), errors::HealthCheckDBError> {
+        self.diesel_store.health_check_db().await
+    }
+
+    async fn health_check_redis(
+        &self,
+        db: &dyn StorageInterface,
+    ) -> CustomResult<(), errors::HealthCheckRedisError> {
+        self.diesel_store.health_check_redis(db).await
+    }
+
+    async fn health_check_locker(
+        &self,
+        state: &routes::AppState,
+    ) -> CustomResult<(), errors::HealthCheckLockerError> {
+        self.diesel_store.health_check_locker(state).await
+    }
+}

crates/router/src/routes/app.rs

@@ -253,9 +253,10 @@ pub struct Health;
 
 impl Health {
     pub fn server(state: AppState) -> Scope {
-        web::scope("")
+        web::scope("health")
             .app_data(web::Data::new(state))
-            .service(web::resource("/health").route(web::get().to(health)))
+            .service(web::resource("").route(web::get().to(health)))
+            .service(web::resource("/deep_check").route(web::post().to(deep_health_check)))
     }
 }
 

crates/router/src/routes/health.rs

@@ -1,7 +1,9 @@
+use actix_web::web;
+use api_models::health_check::RouterHealthCheckResponse;
 use router_env::{instrument, logger, tracing};
 
-use crate::routes::metrics;
+use super::app;
-
+use crate::{routes::metrics, services};
 /// .
 // #[logger::instrument(skip_all, name = "name1", level = "warn", fields( key1 = "val1" ))]
 #[instrument(skip_all)]
@@ -11,3 +13,59 @@ pub async fn health() -> impl actix_web::Responder {
     logger::info!("Health was called");
     actix_web::HttpResponse::Ok().body("health is good")
 }
+
+#[instrument(skip_all)]
+pub async fn deep_health_check(state: web::Data<app::AppState>) -> impl actix_web::Responder {
+    metrics::HEALTH_METRIC.add(&metrics::CONTEXT, 1, &[]);
+    let db = &*state.store;
+    let mut status_code = 200;
+    logger::info!("Deep health check was called");
+
+    logger::debug!("Database health check begin");
+
+    let db_status = match db.health_check_db().await {
+        Ok(_) => "Health is good".to_string(),
+        Err(err) => {
+            status_code = 500;
+            err.to_string()
+        }
+    };
+    logger::debug!("Database health check end");
+
+    logger::debug!("Redis health check begin");
+
+    let redis_status = match db.health_check_redis(db).await {
+        Ok(_) => "Health is good".to_string(),
+        Err(err) => {
+            status_code = 500;
+            err.to_string()
+        }
+    };
+
+    logger::debug!("Redis health check end");
+
+    logger::debug!("Locker health check begin");
+
+    let locker_status = match db.health_check_locker(&state).await {
+        Ok(_) => "Health is good".to_string(),
+        Err(err) => {
+            status_code = 500;
+            err.to_string()
+        }
+    };
+
+    logger::debug!("Locker health check end");
+
+    let response = serde_json::to_string(&RouterHealthCheckResponse {
+        database: db_status,
+        redis: redis_status,
+        locker: locker_status,
+    })
+    .unwrap_or_default();
+
+    if status_code == 200 {
+        services::http_response_json(response)
+    } else {
+        services::http_server_error_json_response(response)
+    }
+}

crates/router/src/services/api.rs

@@ -1138,6 +1138,14 @@ pub fn http_response_json<T: body::MessageBody + 'static>(response: T) -> HttpRe
         .body(response)
 }
 
+pub fn http_server_error_json_response<T: body::MessageBody + 'static>(
+    response: T,
+) -> HttpResponse {
+    HttpResponse::InternalServerError()
+        .content_type(mime::APPLICATION_JSON)
+        .body(response)
+}
+
 pub fn http_response_json_with_headers<T: body::MessageBody + 'static>(
     response: T,
     mut headers: Vec<(String, String)>,

crates/router/src/services/api/client.rs

@@ -10,6 +10,7 @@ use router_env::tracing_actix_web::RequestId;
 use super::{request::Maskable, Request};
 use crate::{
     configs::settings::{Locker, Proxy},
+    consts::LOCKER_HEALTH_CALL_PATH,
     core::{
         errors::{ApiClientError, CustomResult},
         payments,
@@ -119,6 +120,7 @@ pub fn proxy_bypass_urls(locker: &Locker) -> Vec<String> {
         format!("{locker_host_rs}/cards/add"),
         format!("{locker_host_rs}/cards/retrieve"),
         format!("{locker_host_rs}/cards/delete"),
+        format!("{locker_host_rs}{}", LOCKER_HEALTH_CALL_PATH),
         format!("{locker_host}/card/addCard"),
         format!("{locker_host}/card/getCard"),
         format!("{locker_host}/card/deleteCard"),

crates/storage_impl/src/errors.rs

@@ -376,3 +376,53 @@ pub enum ConnectorError {
     #[error("Missing 3DS redirection payload: {field_name}")]
     MissingConnectorRedirectionPayload { field_name: &'static str },
 }
+
+#[derive(Debug, thiserror::Error)]
+pub enum HealthCheckDBError {
+    #[error("Error while connecting to database")]
+    DBError,
+    #[error("Error while writing to database")]
+    DBWriteError,
+    #[error("Error while reading element in the database")]
+    DBReadError,
+    #[error("Error while deleting element in the database")]
+    DBDeleteError,
+    #[error("Unpredictable error occurred")]
+    UnknownError,
+    #[error("Error in database transaction")]
+    TransactionError,
+}
+
+impl From<diesel::result::Error> for HealthCheckDBError {
+    fn from(error: diesel::result::Error) -> Self {
+        match error {
+            diesel::result::Error::DatabaseError(_, _) => Self::DBError,
+
+            diesel::result::Error::RollbackErrorOnCommit { .. }
+            | diesel::result::Error::RollbackTransaction
+            | diesel::result::Error::AlreadyInTransaction
+            | diesel::result::Error::NotInTransaction
+            | diesel::result::Error::BrokenTransactionManager => Self::TransactionError,
+
+            _ => Self::UnknownError,
+        }
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum HealthCheckRedisError {
+    #[error("Failed to establish Redis connection")]
+    RedisConnectionError,
+    #[error("Failed to set key value in Redis")]
+    SetFailed,
+    #[error("Failed to get key value in Redis")]
+    GetFailed,
+    #[error("Failed to delete key value in Redis")]
+    DeleteFailed,
+}
+
+#[derive(Debug, Clone, thiserror::Error)]
+pub enum HealthCheckLockerError {
+    #[error("Failed to establish Locker connection")]
+    FailedToCallLocker,
+}