From e93fce26b60b24301aa3fc3a0e87e56ec347816a Mon Sep 17 00:00:00 2001
From: Shivansh Mathur
 <104988143+ShivanshMathurJuspay@users.noreply.github.com>
Date: Thu, 20 Mar 2025 19:23:04 +0530
Subject: [PATCH] fix(analytics): retry implementation for forex crate call
 (#7280)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>
Co-authored-by: Sandeep Kumar <sandeep.kumar@juspay.in>
---
 crates/router/src/consts.rs        |  3 ++
 crates/router/src/core/currency.rs | 48 ++++++++++++++++++++++++++----
 2 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/crates/router/src/consts.rs b/crates/router/src/consts.rs
index 0fce7048e6..d6872bcf06 100644
--- a/crates/router/src/consts.rs
+++ b/crates/router/src/consts.rs
@@ -229,3 +229,6 @@ pub(crate) const PROTOCOL: &str = "ECv2";
 
 /// Sender ID for Google Pay Decryption
 pub(crate) const SENDER_ID: &[u8] = b"Google";
+
+/// Default value for the number of attempts to retry fetching forex rates
+pub const DEFAULT_ANALYTICS_FOREX_RETRY_ATTEMPTS: u64 = 3;
diff --git a/crates/router/src/core/currency.rs b/crates/router/src/core/currency.rs
index bc63dc878c..43b63cd6e6 100644
--- a/crates/router/src/core/currency.rs
+++ b/crates/router/src/core/currency.rs
@@ -2,11 +2,13 @@ use analytics::errors::AnalyticsError;
 use common_utils::errors::CustomResult;
 use currency_conversion::types::ExchangeRates;
 use error_stack::ResultExt;
+use router_env::logger;
 
 use crate::{
+    consts::DEFAULT_ANALYTICS_FOREX_RETRY_ATTEMPTS,
     core::errors::ApiErrorResponse,
     services::ApplicationResponse,
-    utils::currency::{self, convert_currency, get_forex_rates},
+    utils::currency::{self, convert_currency, get_forex_rates, ForexError as ForexCacheError},
     SessionState,
 };
 
@@ -48,9 +50,45 @@ pub async fn get_forex_exchange_rates(
     state: SessionState,
 ) -> CustomResult<ExchangeRates, AnalyticsError> {
     let forex_api = state.conf.forex_api.get_inner();
-    let rates = get_forex_rates(&state, forex_api.data_expiration_delay_in_seconds)
-        .await
-        .change_context(AnalyticsError::ForexFetchFailed)?;
+    let mut attempt = 1;
 
-    Ok((*rates.data).clone())
+    logger::info!("Starting forex exchange rates fetch");
+    loop {
+        logger::info!("Attempting to fetch forex rates - Attempt {attempt} of {DEFAULT_ANALYTICS_FOREX_RETRY_ATTEMPTS}");
+
+        match get_forex_rates(&state, forex_api.data_expiration_delay_in_seconds).await {
+            Ok(rates) => {
+                logger::info!("Successfully fetched forex rates");
+                return Ok((*rates.data).clone());
+            }
+            Err(error) => {
+                let is_retryable = matches!(
+                    error.current_context(),
+                    ForexCacheError::CouldNotAcquireLock
+                        | ForexCacheError::EntryNotFound
+                        | ForexCacheError::ForexDataUnavailable
+                        | ForexCacheError::LocalReadError
+                        | ForexCacheError::LocalWriteError
+                        | ForexCacheError::RedisConnectionError
+                        | ForexCacheError::RedisLockReleaseFailed
+                        | ForexCacheError::RedisWriteError
+                        | ForexCacheError::WriteLockNotAcquired
+                );
+
+                if !is_retryable {
+                    return Err(error.change_context(AnalyticsError::ForexFetchFailed));
+                }
+
+                if attempt >= DEFAULT_ANALYTICS_FOREX_RETRY_ATTEMPTS {
+                    logger::error!("Failed to fetch forex rates after {DEFAULT_ANALYTICS_FOREX_RETRY_ATTEMPTS} attempts");
+                    return Err(error.change_context(AnalyticsError::ForexFetchFailed));
+                }
+                logger::warn!(
+                    "Forex rates fetch failed with retryable error, retrying in {attempt} seconds"
+                );
+                tokio::time::sleep(std::time::Duration::from_secs(attempt * 2)).await;
+                attempt += 1;
+            }
+        }
+    }
 }