fix: Spring mapper props in Tzatziki by default (#60)

* fix: Spring mapper props in Tzatziki by default

* fix: Tests are more readable

* fix: Ability to disable the copyNamingStrategyFromSpringMapper behaviour

* fix: doc for copyNamingStrategyFromSpringMapper behaviour

Author: brian-mulier

tzatziki-spring/README.md

@@ -130,6 +130,19 @@ HttpInterceptor.disable();
 If you wish to intercept requests for another client than the supported ones, 
 you can have a look at the `com.decathlon.tzatziki.spring.HttpInterceptor` code and write your own interceptor.
 
+## JacksonMapper's property naming strategy override
+
+By default, JacksonMapper will use the Spring context's ObjectMapper naming strategy.
+If you want to disable it and override it with another:
+
+Disable the Spring property naming strategy copy behaviour and override with the wanted one in your runner (HelloApplicationSteps):
+```java
+static {
+    SpringSteps.copyNamingStrategyFromSpringMapper = false;
+    JacksonMapper.with(objectMapper -> objectMapper.setPropertyNamingStrategy(PropertyNamingStrategies.WANTED_STRATEGY));
+}
+```
+
 ## Steps local to this library
 
 This library doesn't come with a lot of steps, but it will start your Spring automatically 

tzatziki-spring/src/main/java/com/decathlon/tzatziki/steps/SpringSteps.java

@@ -1,7 +1,9 @@
 package com.decathlon.tzatziki.steps;
 
 import com.decathlon.tzatziki.utils.Guard;
+import com.decathlon.tzatziki.utils.JacksonMapper;
 import com.decathlon.tzatziki.utils.Mapper;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import io.cucumber.java.Before;
 import io.cucumber.java.en.Given;
 import io.cucumber.java.en.Then;
@@ -17,7 +19,6 @@
 import java.util.Objects;
 import java.util.function.Predicate;
 
-import static com.decathlon.tzatziki.utils.Asserts.awaitUntilAsserted;
 import static com.decathlon.tzatziki.utils.Asserts.equalsInAnyOrder;
 import static com.decathlon.tzatziki.utils.Guard.GUARD;
 import static com.decathlon.tzatziki.utils.Guard.always;
@@ -32,9 +33,13 @@ public class SpringSteps {
     private ApplicationContext applicationContext;
     @Autowired(required = false)
     private List<CacheManager> cacheManagers;
+    @Autowired(required = false)
+    private ObjectMapper objectMapper;
     @LocalServerPort
     private int localServerPort;
 
+    public static boolean copyNamingStrategyFromSpringMapper = true;
+
     public SpringSteps(ObjectSteps objects, HttpSteps http) {
         this.objects = objects;
         this.http = http;
@@ -44,11 +49,16 @@ public ApplicationContext applicationContext() {
         return applicationContext;
     }
 
-    @Before
+    @Before(order = -1)
     public void before() {
         http.setRelativeUrlRewriter(path -> "http://localhost:%s%s".formatted(localServerPort, path));
         if (applicationContext != null) {
             we_clear_all_the_caches(always());
+
+            if (copyNamingStrategyFromSpringMapper) {
+                JacksonMapper.with(mapper -> mapper.setPropertyNamingStrategy(objectMapper.getPropertyNamingStrategy()));
+                copyNamingStrategyFromSpringMapper = false;
+            }
         }
     }
 

tzatziki-spring/src/test/java/com/decathlon/tzatziki/app/TestApplication.java

@@ -1,5 +1,7 @@
 package com.decathlon.tzatziki.app;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.web.client.RestTemplateBuilder;
@@ -21,6 +23,13 @@ public RestTemplate restTemplate() {
         return new RestTemplate();
     }
 
+    @Bean
+    public ObjectMapper objectMapperSnakeCase() {
+        final ObjectMapper mapper = new ObjectMapper();
+        mapper.setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE);
+        return mapper;
+    }
+
     @Bean
     public RestTemplateBuilder restTemplateBuilder() {
         return new RestTemplateBuilder();

tzatziki-spring/src/test/java/com/decathlon/tzatziki/app/beans/NonSnakeCasePojo.java

@@ -0,0 +1,8 @@
+package com.decathlon.tzatziki.app.beans;
+
+import lombok.Data;
+
+@Data
+public class NonSnakeCasePojo {
+    private String nonSnakeCaseField;
+}

tzatziki-spring/src/test/java/com/decathlon/tzatziki/steps/TestApplicationSteps.java

@@ -2,6 +2,8 @@
 
 import com.decathlon.tzatziki.app.TestApplication;
 import com.decathlon.tzatziki.spring.HttpInterceptor;
+import com.decathlon.tzatziki.utils.JacksonMapper;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import io.cucumber.java.Before;
 import io.cucumber.java.en.Then;
 import io.cucumber.spring.CucumberContextConfiguration;
@@ -18,7 +20,6 @@
 @ContextConfiguration(initializers = TestApplicationSteps.Initializer.class)
 @Slf4j
 public class TestApplicationSteps {
-
     static class Initializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
 
         public void initialize(ConfigurableApplicationContext configurableApplicationContext) {

tzatziki-spring/src/test/resources/com/decathlon/tzatziki/steps/spring.feature

@@ -48,4 +48,10 @@ Feature: to interact with a spring boot service
     When we call "http://www.google.com"
     Then we receive a status 200
     But if calling "http://www.google.com" will return a status FORBIDDEN_403
-    Then calling "http://www.google.com" returns a status FORBIDDEN_403
+    Then calling "http://www.google.com" returns a status FORBIDDEN_403
+
+  Scenario: we should use Spring Context's mapper PropertyNamingStrategy by default (snake_case)
+    Then it is not true that a JsonMappingException is thrown when myPojo is a NonSnakeCasePojo:
+    """
+    non_snake_case_field: hello
+    """