From 81c7601325fc8e271191be53175c47ed5de750d8 Mon Sep 17 00:00:00 2001
From: sthompsonCH <105206260+sthompsonCH@users.noreply.github.com>
Date: Wed, 22 Jan 2025 11:26:05 +0000
Subject: [PATCH] DSND-3213: Handle 404 from exemptions api (#167)

* Behaviour has been changed to return an empty optional when exemptions GET returns 404. Rather than throw an exception. It's possible to have PSCs without exemptions.
---
 .../service/CompanyExemptionsApiService.java           | 10 +++-------
 .../service/CompanyExemptionsApiServiceTest.java       |  6 +++---
 2 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/src/main/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiService.java b/src/main/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiService.java
index 64f87927..c8d812c8 100644
--- a/src/main/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiService.java
+++ b/src/main/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiService.java
@@ -15,7 +15,6 @@
 import uk.gov.companieshouse.logging.Logger;
 import uk.gov.companieshouse.logging.LoggerFactory;
 import uk.gov.companieshouse.pscdataapi.exceptions.BadGatewayException;
-import uk.gov.companieshouse.pscdataapi.exceptions.ResourceNotFoundException;
 import uk.gov.companieshouse.pscdataapi.logging.DataMapHolder;
 
 @Component
@@ -31,7 +30,7 @@ public CompanyExemptionsApiService(
     }
 
     public Optional<CompanyExemptions> getCompanyExemptions(final String companyNumber) {
-        ApiResponse<CompanyExemptions> response;
+        ApiResponse<CompanyExemptions> response = null;
         try {
             response = exemptionsApiClientSupplier.get()
                     .privateDeltaResourceHandler()
@@ -39,12 +38,9 @@ public Optional<CompanyExemptions> getCompanyExemptions(final String companyNumb
                     .execute();
         } catch (ApiErrorResponseException ex) {
             final int statusCode = ex.getStatusCode();
-            LOGGER.info("Company Exemptions API call failed with status code [%s]".formatted(statusCode),
+            LOGGER.info("Company Exemptions API GET failed with status code [%s]".formatted(statusCode),
                     DataMapHolder.getLogMap());
-            if (statusCode == 404) {
-                throw new ResourceNotFoundException(HttpStatus.NOT_FOUND,
-                        "Company Exemptions API responded with 404 Not Found");
-            } else {
+            if (statusCode != 404) {
                 throw new BadGatewayException("Error calling Company Exemptions API endpoint", ex);
             }
         } catch (URIValidationException ex) {
diff --git a/src/test/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiServiceTest.java b/src/test/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiServiceTest.java
index a5ace2c5..523cfa7c 100644
--- a/src/test/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiServiceTest.java
+++ b/src/test/java/uk/gov/companieshouse/pscdataapi/service/CompanyExemptionsApiServiceTest.java
@@ -89,7 +89,7 @@ void shouldGetCompanyExemptionsWithNullResponseAndReturnEmptyOptional() throws E
     }
 
     @Test
-    void shouldThrowResourceNotFoundExceptionWhenApiRespondsWith404NotFound() throws Exception {
+    void shouldReturnEmptyOptionalWhenApiRespondsWith404NotFound() throws Exception {
         // given
         when(supplier.get()).thenReturn(client);
         when(client.privateDeltaResourceHandler()).thenReturn(privateDeltaResourceHandler);
@@ -98,11 +98,11 @@ void shouldThrowResourceNotFoundExceptionWhenApiRespondsWith404NotFound() throws
         when(privateCompanyExemptionsGetAll.execute()).thenThrow(buildApiErrorResponseException(404));
 
         // when
-        Executable executable = () -> service.getCompanyExemptions(COMPANY_NUMBER);
+        final Optional<CompanyExemptions> actual = service.getCompanyExemptions(COMPANY_NUMBER);
 
         // then
-        assertThrows(ResourceNotFoundException.class, executable);
         verify(privateDeltaResourceHandler).getCompanyExemptionsResource(URL);
+        assertEquals(Optional.empty(), actual);
     }
 
     @ParameterizedTest