From 140da0a89eaf5e72462503f9e27290bf10803462 Mon Sep 17 00:00:00 2001
From: Wendy Hu <wendy.hu@alumni.stonybrook.edu>
Date: Wed, 23 Aug 2023 09:58:14 -0400
Subject: [PATCH 1/2] feat(synapse-client-rest): adding retry method to
 reactive rest client

---
 .../rest/client/BaseReactiveRestClient.java   | 35 +++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/client/synapse-client-rest/src/main/java/io/americanexpress/synapse/client/rest/client/BaseReactiveRestClient.java b/client/synapse-client-rest/src/main/java/io/americanexpress/synapse/client/rest/client/BaseReactiveRestClient.java
index 7c3d0e455..e00328ee9 100644
--- a/client/synapse-client-rest/src/main/java/io/americanexpress/synapse/client/rest/client/BaseReactiveRestClient.java
+++ b/client/synapse-client-rest/src/main/java/io/americanexpress/synapse/client/rest/client/BaseReactiveRestClient.java
@@ -13,9 +13,12 @@
  */
 package io.americanexpress.synapse.client.rest.client;
 
+import java.time.Duration;
 import java.util.List;
 
 import io.americanexpress.synapse.client.rest.factory.BaseClientHttpHeadersFactory;
+import io.americanexpress.synapse.framework.exception.ApplicationClientException;
+import io.americanexpress.synapse.framework.exception.model.ErrorCode;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
@@ -29,6 +32,7 @@
 import io.americanexpress.synapse.client.rest.model.QueryParameter;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
+import reactor.util.retry.Retry;
 
 /**
  * {@code BaseReactiveRestClient} class specifies the prototypes for all reactive REST clients.
@@ -113,6 +117,37 @@ public Mono<O> callMonoService(HttpHeaders headers, I clientRequest, List<QueryP
 			.bodyToMono(clientResponseType);
 	}
 
+	/**
+	 * Get the mono response from the service given the HTTP headers and request body. If call to service fails,
+	 * can retry after delayInMilliSeconds and will retry up to numberOfRetries.
+	 *
+	 * @param headers      headers for the back end service
+	 * @param clientRequest      body of the request
+	 * @param numberOfRetries the max number of retries
+	 * @param delayInMilliSeconds the delay between retry attempts in milliseconds
+	 * @param queryParameters    parameters needed to be added to URI
+	 * @param pathVariables      variables needed to be added to URI
+	 * @return the mono response body from the back end service
+	 */
+	public Mono<O> callMonoServiceWithRetry(HttpHeaders headers, I clientRequest, int numberOfRetries, long delayInMilliSeconds, List<QueryParameter> queryParameters, String... pathVariables) {
+		// Get the updated URL which may change in each client request due to path variables and/or query parameters
+		String updatedUrl = UrlBuilder.build(url, queryParameters, pathVariables);
+
+		return webClient.method(httpMethod)
+				.uri(updatedUrl)
+				.headers(httpHeaders ->
+						httpHeaders.addAll(httpHeadersFactory.create(headers, clientRequest, updatedUrl)))
+				.body(Mono.just(clientRequest), clientRequestType)
+				.retrieve()
+				.onStatus(HttpStatus::isError, reactiveRestResponseErrorHandler)
+				.bodyToMono(clientResponseType)
+				.retryWhen(Retry.fixedDelay(numberOfRetries, Duration.ofMillis(delayInMilliSeconds))
+					.filter(throwable -> throwable instanceof ApplicationClientException applicationClientException && applicationClientException.getErrorCode() == ErrorCode.GENERIC_5XX_ERROR)
+						.onRetryExhaustedThrow((retryBackoffSpec, retrySignal) -> {
+									throw new ApplicationClientException("External Service failed to process after max retries", ErrorCode.GENERIC_5XX_ERROR);
+						}));
+	}
+
 	/**
 	 * Get the mono response entity from the service given the HTTP headers and request body.
 	 *

From fbdb391e9525245a441b7dd414245d5ef4d7f276 Mon Sep 17 00:00:00 2001
From: Wendy Hu <wendy.hu@alumni.stonybrook.edu>
Date: Wed, 23 Aug 2023 10:01:32 -0400
Subject: [PATCH 2/2] fix(): fixing failing build

---
 data/data-samples/sample-data-oracle-reactive-cp-book/pom.xml   | 2 +-
 .../sample-service-reactive-oracle-cp-book/pom.xml              | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/data/data-samples/sample-data-oracle-reactive-cp-book/pom.xml b/data/data-samples/sample-data-oracle-reactive-cp-book/pom.xml
index 2e5db5f7a..25c9caa5c 100644
--- a/data/data-samples/sample-data-oracle-reactive-cp-book/pom.xml
+++ b/data/data-samples/sample-data-oracle-reactive-cp-book/pom.xml
@@ -18,7 +18,7 @@
     <parent>
         <artifactId>data-samples</artifactId>
         <groupId>io.americanexpress.synapse</groupId>
-        <version>0.3.21-SNAPSHOT</version>
+        <version>0.3.23-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 
diff --git a/service/service-samples/sample-service-reactive-oracle-cp-book/pom.xml b/service/service-samples/sample-service-reactive-oracle-cp-book/pom.xml
index fb990b3c6..ce0df8581 100644
--- a/service/service-samples/sample-service-reactive-oracle-cp-book/pom.xml
+++ b/service/service-samples/sample-service-reactive-oracle-cp-book/pom.xml
@@ -18,7 +18,7 @@
     <parent>
         <groupId>io.americanexpress.synapse</groupId>
         <artifactId>service-samples</artifactId>
-        <version>0.3.21-SNAPSHOT</version>
+        <version>0.3.23-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>