MAT-4091 Modify the Error message returned from CQL-ELM Translator

pom.xml

@@ -4,7 +4,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>gov.cms.madie</groupId>
 	<artifactId>madie-translator-commons</artifactId>
-	<version>0.0.4-SNAPSHOT</version>
+	<version>0.0.5-SNAPSHOT</version>
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<java.version>17</java.version>

src/main/java/gov/cms/madie/cql_elm_translator/exceptions/LibraryResourceLoaderException.java

@@ -0,0 +1,7 @@
+package gov.cms.madie.cql_elm_translator.exceptions;
+
+public class LibraryResourceLoaderException extends RuntimeException {
+  public LibraryResourceLoaderException(String message) {
+    super(message);
+  }
+}

src/main/java/gov/cms/madie/cql_elm_translator/service/CqlLibraryService.java

@@ -1,5 +1,6 @@
 package gov.cms.madie.cql_elm_translator.service;
 
+import gov.cms.madie.cql_elm_translator.exceptions.LibraryResourceLoaderException;
 import gov.cms.madie.cql_elm_translator.utils.cql.cql_translator.MadieLibrarySourceProvider;
 import gov.cms.mat.cql.CqlTextParser;
 import gov.cms.mat.cql.elements.UsingProperties;
@@ -10,9 +11,9 @@
 import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
-import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
+import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.RestTemplate;
 import org.springframework.web.util.UriComponentsBuilder;
 import java.net.URI;
@@ -45,10 +46,9 @@ public String getLibraryCql(String name, String version, String accessToken) {
     HttpHeaders headers = new HttpHeaders();
     headers.add("Authorization", accessToken);
 
-    ResponseEntity<String> responseEntity =
-        restTemplate.exchange(uri, HttpMethod.GET, new HttpEntity<>(headers), String.class);
-
-    if (responseEntity.getStatusCode().is2xxSuccessful()) {
+    try {
+      ResponseEntity<String> responseEntity =
+          restTemplate.exchange(uri, HttpMethod.GET, new HttpEntity<>(headers), String.class);
       if (responseEntity.hasBody()) {
         log.debug("Retrieved a valid cqlPayload");
         List<String> supportedLibraries =
@@ -79,15 +79,19 @@ public String getLibraryCql(String name, String version, String accessToken) {
         log.error("Cannot find Cql payload in the response");
         return null;
       }
-    } else if (responseEntity.getStatusCode().equals(HttpStatus.NOT_FOUND)) {
-      log.error("Cannot find a Cql Library with name: {}, version: {}", name, version);
-    } else if (responseEntity.getStatusCode().equals(HttpStatus.CONFLICT)) {
-      log.error(
-          "Multiple libraries found with name: {}, version: {}, but only one was expected",
-          name,
-          version);
+    } catch (HttpClientErrorException.NotFound ex) {
+      String message =
+          String.format("Library resource %s version '%s' is not found.", name, version);
+      log.error(message);
+      throw new LibraryResourceLoaderException(message);
+    } catch (HttpClientErrorException.Conflict ex) {
+      String message =
+          String.format(
+              "Multiple libraries found with name: %s, version: %s, but only one was expected.",
+              name, version);
+      log.error(message);
+      throw new LibraryResourceLoaderException(message);
     }
-    return null;
   }
 
   private URI buildMadieLibraryServiceUri(String name, String version) {

src/test/java/gov/cms/madie/cql_elm_translator/services/CqlLibraryServiceTest.java

@@ -1,5 +1,6 @@
 package gov.cms.madie.cql_elm_translator.services;
 
+import gov.cms.madie.cql_elm_translator.exceptions.LibraryResourceLoaderException;
 import gov.cms.mat.cql.elements.UsingProperties;
 import gov.cms.madie.cql_elm_translator.service.CqlLibraryService;
 import gov.cms.madie.cql_elm_translator.utils.cql.cql_translator.MadieLibrarySourceProvider;
@@ -16,17 +17,18 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.test.util.ReflectionTestUtils;
+import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.RestTemplate;
 
 import java.net.URI;
 import java.net.URISyntaxException;
 
 import static org.hamcrest.CoreMatchers.notNullValue;
 import static org.junit.jupiter.api.Assertions.*;
-import static org.mockito.Mockito.when;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.is;
+import static org.mockito.Mockito.*;
 
 @ExtendWith(MockitoExtension.class)
 class CqlLibraryServiceTest {
@@ -39,7 +41,7 @@ class CqlLibraryServiceTest {
 
   private URI libraryUri;
 
-  private final String cqlLibraryName = "cqlLibraryName";
+  private final String cqlLibraryName = "FHIRHelpers";
 
   private final String cqlLibraryVersion = "1.0.000";
 
@@ -106,23 +108,35 @@ void getLibraryCqlReturnsNull() {
   }
 
   @Test
-  void getLibraryCqlReturnsNullWhenNotFound() {
-    when(restTemplate.exchange(
-            libraryUri, HttpMethod.GET, new HttpEntity<>(httpHeaders), String.class))
-        .thenReturn(new ResponseEntity<>(null, HttpStatus.NOT_FOUND));
-    String responseBody =
-        cqlLibraryService.getLibraryCql(cqlLibraryName, cqlLibraryVersion, accessToken);
-    assertNull(responseBody);
+  void getLibraryCqlWhenLibraryNotFound() {
+    HttpClientErrorException response = mock(HttpClientErrorException.NotFound.class);
+    doThrow(response)
+        .when(restTemplate)
+        .exchange(libraryUri, HttpMethod.GET, new HttpEntity<>(httpHeaders), String.class);
+    Exception ex =
+        assertThrows(
+            LibraryResourceLoaderException.class,
+            () -> cqlLibraryService.getLibraryCql(cqlLibraryName, cqlLibraryVersion, accessToken));
+    assertThat(
+        ex.getMessage(),
+        is(equalTo("Library resource FHIRHelpers version '1.0.000' is not found.")));
   }
 
   @Test
   void getLibraryCqlReturnsNullWhenConflict() {
-    when(restTemplate.exchange(
-            libraryUri, HttpMethod.GET, new HttpEntity<>(httpHeaders), String.class))
-        .thenReturn(new ResponseEntity<>(null, HttpStatus.CONFLICT));
-    String responseBody =
-        cqlLibraryService.getLibraryCql(cqlLibraryName, cqlLibraryVersion, accessToken);
-    assertNull(responseBody);
+    HttpClientErrorException response = mock(HttpClientErrorException.Conflict.class);
+    doThrow(response)
+        .when(restTemplate)
+        .exchange(libraryUri, HttpMethod.GET, new HttpEntity<>(httpHeaders), String.class);
+    Exception ex =
+        assertThrows(
+            LibraryResourceLoaderException.class,
+            () -> cqlLibraryService.getLibraryCql(cqlLibraryName, cqlLibraryVersion, accessToken));
+    assertThat(
+        ex.getMessage(),
+        is(
+            equalTo(
+                "Multiple libraries found with name: FHIRHelpers, version: 1.0.000, but only one was expected.")));
   }
 
   @Test