Editing SpringBoot (section)

==Concepts==
* SpringBoot Autoconfiguration: by scanning the classpath
* Dispatcher Servlet
* SpringBoot Actuator (for monitoring)

===Architecture===
* Client -> Controller -> Service (Business Logic) -> Model


===[[Rest|Rest]]===
* see [https://spring.io/guides/tutorials/rest/ here]

===Application Context===
The '''ApplicationContext''' is where Spring holds instances of objects that it has identified to be managed and distributed automatically. These are called [[#Beans|Beans]]. The application context can also be autowired:
 @Autowired
 private ApplicationContext applicationContext;

===Dependency Injection===

===Beans===
* Beans are specified by class level annotations e.g. <code>@Component, @Service, @Repository</code> etc. or by XML configuration. The annotations are hierachical meaning for example that there are more specialized annotations for <code>@Component</code>. 
*<code>@Bean</code> is a special annotation on method level.
* A java class becomes Spring Bean only when it is created by Spring
* On startup/runtime classes in the application will be scanned and each class annotated with spring annotations will be instantiated as beans and put into a global context (Spring applicationcontext). 
* Entities are no beans
* You can autowire only those beans whose life-cycle are managed by Spring IoC container.
* Spring support @Autowire only for Spring Beans
* the default scope is singleton

===Security===
adding to <code>pom.xml</code>:
 <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>'''spring-boot-starter-security'''</artifactId>
 </dependency>
and update the project automatically sets up '''form-based authentication''' with a generated session cookie generated on the server or '''basic authentication''' with a header sent along with every request
* user='user
* pwd=see console output of server start
or set it in <code>[[#Application_Properties|application.properties]]</code>
 spring.security.user.name=uwe
 spring.security.user.password=uwe
This has to be entered just once.

===Testing===
 <dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>'''spring-boot-starter-test'''</artifactId>
   <scope>test</scope>
 </dependency>

This integrates the frameworks JUnit, Hamcrest, Mockito,

When you build a Spring boot application using Spring Initializer. It auto creates a <code>@SpringBootTest</code> annotated class for you with <code>contextLoads()</code> empty method. <code>@SpringBootTest</code> by default starts searching in the current package of the test class and then searches upwards through the package structure, looking for a class annotated with <code>@SpringBootConfiguration</code> from which it then reads the configuration to create an application context.

====TestRestTemplate====
* TestRestTemplate is part of the Spring Boot Test module and provides a high-level, programmatic way to test RESTful services by making actual HTTP requests to the service. It allows you to send HTTP requests (GET, POST, PUT, DELETE, etc.) to your application's REST endpoints and receive actual HTTP responses. 
* It starts an embedded server (typically an embedded Tomcat or Jetty instance) and sends requests to the server as if they were real HTTP requests. 
* TestRestTemplate is more suitable for integration testing and end-to-end testing because it interacts with the running server, making actual network calls.

====MockMvc====
* MockMvc, on the other hand, is a part of the Spring Test framework and is specifically designed for testing the controllers of your Spring application in isolation. 
* It allows you to perform requests against your controller methods without starting a full server. 
* With MockMvc, you can simulate HTTP requests and responses without making actual network calls. This makes it a more suitable choice for unit testing and integration testing of your Spring MVC controllers. 
* MockMvc provides a fluent and expressive API for setting up requests, sending them to your controllers, and then validating the results.