Add open api validation test

Author: stephenokeefe

build.gradle

@@ -515,6 +515,8 @@ dependencies {
 
   testImplementation group: 'org.jeasy', name: 'easy-random-core', version: '5.0.0'
 
+  integrationTestImplementation 'com.atlassian.oai:swagger-request-validator-core:2.46.0'
+
   compileJava.dependsOn = openApiGenerateTaskList
 }
 

src/integrationTest/java/uk/gov/hmcts/darts/transcriptions/api/TranscriptionOpenApiContractTest.java

@@ -0,0 +1,33 @@
+package uk.gov.hmcts.darts.transcriptions.api;
+
+import com.atlassian.oai.validator.OpenApiInteractionValidator;
+import com.atlassian.oai.validator.model.Request;
+import com.atlassian.oai.validator.model.SimpleRequest;
+import com.atlassian.oai.validator.report.ValidationReport;
+import lombok.extern.slf4j.Slf4j;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@Slf4j
+class TranscriptionOpenApiContractTest {
+
+    private static final OpenApiInteractionValidator VALIDATOR =
+        OpenApiInteractionValidator.createForSpecificationUrl(
+            TranscriptionOpenApiContractTest.class
+                .getResource("/openapi/transcriptions.yaml")
+                .toExternalForm()
+        ).build();
+
+    @Test
+    void negativeTranscriptionId() {
+        Request request = SimpleRequest.Builder
+            .get("/transcriptions/-1/document")
+            .build();
+
+        ValidationReport report = VALIDATOR.validateRequest(request);
+
+        assertTrue(report.hasErrors());
+        report.getMessages().forEach(m -> log.info(m.getMessage()));
+    }
+}