Step 09

Step09.md

@@ -1,16 +1,383 @@
 ##What You Will Learn during this Step:
-- First
-- Second
-- Third
+- Create a REST Service to add a new question to survey
+ - @PostMapping("/surveys/{surveyId}/questions")
+ - @RequestBody Question question
+ - ResponseEntity.created(location).build()
+ - ResponseEntity.noContent().build()
 
 ## Useful Snippets and References
 First Snippet
 ```
+    @PostMapping("/surveys/{surveyId}/questions")
+    ResponseEntity<?> add(@PathVariable String surveyId,
+            @RequestBody Question question) {
+
+        Question createdTodo = surveyService.addQuestion(surveyId, question);
+
+        if (createdTodo == null) {
+            return ResponseEntity.noContent().build();
+        }
+
+        URI location = ServletUriComponentsBuilder.fromCurrentRequest()
+                .path("/{id}").buildAndExpand(createdTodo.getId()).toUri();
+
+        return ResponseEntity.created(location).build();
+
+    }
 ```
-Second Snippet
+
+## Exercises
+- Create more REST services of your choice
+
+## Files List
+### /pom.xml
+```
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.in28minutes</groupId>
+    <artifactId>springboot-for-beginners-example</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>Your First Spring Boot Example</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>1.4.0.RELEASE</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <java.version>1.8</java.version>
+    </properties>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+</project>
 ```
+### /src/main/java/com/in28minutes/springboot/Application.java
 ```
+package com.in28minutes.springboot;
 
-## Exercises
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.ApplicationContext;
+import org.springframework.stereotype.Component;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        ApplicationContext ctx = SpringApplication.run(Application.class, args);
+
+    }
+
+    @RestController
+    class SomeBean {
+
+        @Autowired
+        private SomeDependency someDependency;
+
+        @RequestMapping("/")
+        public String index() {
+            return someDependency.getSomething();
+        }
+
+    }
+
+    @Component
+    class SomeDependency {
+
+        public String getSomething() {
+            return "Hello! Welcome!";
+        }
+
+    }
+
+}
+```
+### /src/main/java/com/in28minutes/springboot/controller/SurveyController.java
+```
+package com.in28minutes.springboot.controller;
+
+import java.util.List;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.in28minutes.springboot.model.Question;
+import com.in28minutes.springboot.service.SurveyService;
+
+@RestController
+class SurveyController {
+    @Autowired
+    private SurveyService surveyService;
+
+    @GetMapping("/surveys/{surveyId}/questions")
+    public List<Question> retrieveQuestions(@PathVariable String surveyId) {
+        return surveyService.retrieveQuestions(surveyId);
+    }
+
+    @GetMapping(path = "/surveys/{surveyId}/questions/{questionId}")
+    public Question retrieveQuestion(@PathVariable String surveyId,
+            @PathVariable String questionId) {
+        return surveyService.retrieveQuestion(surveyId, questionId);
+    }
+
+}
+```
+### /src/main/java/com/in28minutes/springboot/model/Question.java
+```
+package com.in28minutes.springboot.model;
+
+import java.util.List;
+
+public class Question {
+    private String id;
+    private String description;
+    private String correctAnswer;
+    private List<String> options;
+
+    // Needed by Caused by: com.fasterxml.jackson.databind.JsonMappingException:
+    // Can not construct instance of com.in28minutes.springboot.model.Question:
+    // no suitable constructor found, can not deserialize from Object value
+    // (missing default constructor or creator, or perhaps need to add/enable
+    // type information?)
+    public Question() {
+
+    }
+
+    public Question(String id, String description, String correctAnswer,
+            List<String> options) {
+        super();
+        this.id = id;
+        this.description = description;
+        this.correctAnswer = correctAnswer;
+        this.options = options;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getDescription() {
+        return description;
+    }
 
-## Files List
+    public String getCorrectAnswer() {
+        return correctAnswer;
+    }
+
+    public List<String> getOptions() {
+        return options;
+    }
+
+    @Override
+    public String toString() {
+        return String
+                .format("Question [id=%s, description=%s, correctAnswer=%s, options=%s]",
+                        id, description, correctAnswer, options);
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + (id == null ? 0 : id.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj == null) {
+            return false;
+        }
+        if (getClass() != obj.getClass()) {
+            return false;
+        }
+        Question other = (Question) obj;
+        if (id == null) {
+            if (other.id != null) {
+                return false;
+            }
+        } else if (!id.equals(other.id)) {
+            return false;
+        }
+        return true;
+    }
+
+}
+```
+### /src/main/java/com/in28minutes/springboot/model/Survey.java
+```
+package com.in28minutes.springboot.model;
+
+import java.util.List;
+
+public class Survey {
+    private String id;
+    private String title;
+    private String description;
+    private List<Question> questions;
+
+    public Survey(String id, String title, String description,
+            List<Question> questions) {
+        super();
+        this.id = id;
+        this.title = title;
+        this.description = description;
+        this.questions = questions;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getDescription() {
+        return description;
+    }
+
+    public List<Question> getQuestions() {
+        return questions;
+    }
+
+    @Override
+    public String toString() {
+        return String.format(
+                "Survey [id=%s, title=%s, description=%s, questions=%s]", id,
+                title, description, questions);
+    }
+
+}
+```
+### /src/main/java/com/in28minutes/springboot/service/SurveyService.java
+```
+package com.in28minutes.springboot.service;
+
+import java.math.BigInteger;
+import java.security.SecureRandom;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.springframework.stereotype.Component;
+
+import com.in28minutes.springboot.model.Question;
+import com.in28minutes.springboot.model.Survey;
+
+@Component
+public class SurveyService {
+    private static List<Survey> surveys = new ArrayList<>();
+    static {
+        Question question1 = new Question("Question1",
+                "Largest Country in the World", "Russia", Arrays.asList(
+                        "India", "Russia", "United States", "China"));
+        Question question2 = new Question("Question2",
+                "Most Populus Country in the World", "China", Arrays.asList(
+                        "India", "Russia", "United States", "China"));
+        Question question3 = new Question("Question3",
+                "Highest GDP in the World", "United States", Arrays.asList(
+                        "India", "Russia", "United States", "China"));
+        Question question4 = new Question("Question4",
+                "Second largest english speaking country", "India",
+                Arrays.asList("India", "Russia", "United States", "China"));
+
+        List<Question> questions = new ArrayList<>(Arrays.asList(question1,
+                question2, question3, question4));
+
+        Survey survey = new Survey("Survey1", "My Favorite Survey",
+                "Description of the Survey", questions);
+
+        surveys.add(survey);
+    }
+
+    public List<Survey> retrieveAllSurveys() {
+        return surveys;
+    }
+
+    public Survey retrieveSurvey(String surveyId) {
+        for (Survey survey : surveys) {
+            if (survey.getId().equals(surveyId)) {
+                return survey;
+            }
+        }
+        return null;
+    }
+
+    public List<Question> retrieveQuestions(String surveyId) {
+        Survey survey = retrieveSurvey(surveyId);
+
+        if (survey == null) {
+            return null;
+        }
+
+        return survey.getQuestions();
+    }
+
+    public Question retrieveQuestion(String surveyId, String questionId) {
+        Survey survey = retrieveSurvey(surveyId);
+
+        if (survey == null) {
+            return null;
+        }
+
+        for (Question question : survey.getQuestions()) {
+            if (question.getId().equals(questionId)) {
+                return question;
+            }
+        }
+
+        return null;
+    }
+
+    private SecureRandom random = new SecureRandom();
+
+    public Question addQuestion(String surveyId, Question question) {
+        Survey survey = retrieveSurvey(surveyId);
+
+        if (survey == null) {
+            return null;
+        }
+
+        String randomId = new BigInteger(130, random).toString(32);
+        question.setId(randomId);
+
+        survey.getQuestions().add(question);
+
+        return question;
+    }
+}
+```
+### /src/main/resources/application.properties
+```
+logging.level.org.springframework: DEBUG
+```