Added: Comment-Service, Logging, Mongo persistence API logic.

build.gradle

@@ -43,7 +43,12 @@ dependencies {
     compile group: 'org.springframework.boot', name: 'spring-boot', version: springBootVersion
     compile group: 'org.springframework.boot', name: 'spring-boot-starter-web', version: springBootVersion
     compile group: 'org.springframework.boot', name: 'spring-boot-starter-test', version: springBootVersion
+    compile group: 'org.springframework.boot', name: 'spring-boot-starter-tomcat', version: springBootVersion
     compile group: 'org.springframework.cloud', name: 'spring-cloud-starter-sleuth', version: springSleuthVersion
+    compile group: 'org.springframework.data', name: 'spring-data-mongodb', version: springMongoDataVersion
+    compile group: 'org.mongodb', name: 'mongodb-driver-sync', version: javaMongoDriverVersion
+    compile group: 'com.google.code.gson', name: 'gson', version: gsonVersion
+    compile group: 'com.google.guava', name: 'guava', version: guavaVersion
     compile group: 'javax.el', name: 'javax.el-api', version: javaxElApiVersion
     compile group: 'org.glassfish', name: 'javax.el', version: glassfishVersion
     providedCompile group: 'javax.servlet', name: 'javax.servlet-api', version: javaxServletVersion

gradle.properties

@@ -13,6 +13,10 @@ javaxElApiVersion=3.0.1-b06
 glassfishVersion=3.0.0
 javaxServletVersion=3.1.0
 tomcatVersion=7.0.63
+springMongoDataVersion=3.0.3.RELEASE
+javaMongoDriverVersion=4.0.5
+gsonVersion=2.8.6
+guavaVersion=11.0.2
 
 # Version and base tags can be overridden at build time.
 TechVaultVersion=0.1.0

src/main/java/TechVault/Application.java

@@ -2,10 +2,21 @@
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
+import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;
 
-@SpringBootApplication
-public class Application {
+@SpringBootApplication(scanBasePackages="TechVault")
+@EnableMongoRepositories(basePackages = "TechVault")
+public class  Application {
     public static void main(String[] args) {
+        System.out.println("Starting Application.....");
         SpringApplication.run(Application.class, args);
     }
+
+    @Bean
+    public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
+        return new PersistenceExceptionTranslationPostProcessor();
+    }
+
 }

src/main/java/TechVault/config/PersistenceConfig.java

@@ -0,0 +1,45 @@
+package TechVault.config;
+
+import java.util.Collection;
+import java.util.Collections;
+
+import com.mongodb.ConnectionString;
+import com.mongodb.MongoClientSettings;
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.mongodb.config.AbstractMongoClientConfiguration;
+
+@Configuration
+public class PersistenceConfig extends AbstractMongoClientConfiguration {
+
+    @Value("${spring.data.mongodb.database}")
+    private String dbName;
+
+    @Value("${spring.data.mongodb.uri}")
+    private String uri;
+
+    @Override
+    protected String getDatabaseName() {
+        return dbName;
+    }
+
+    @Override
+    public MongoClient mongoClient() {
+        //"mongodb+srv://prateek:p@cluster0.kf3n4.mongodb.net/TechVault?retryWrites=true&w=majority"
+        ConnectionString connectionString = new ConnectionString(uri);
+        MongoClientSettings mongoClientSettings = MongoClientSettings.builder()
+            .applyConnectionString(connectionString)
+            .build();
+
+        return MongoClients.create(mongoClientSettings);
+    }
+
+    @Override
+    public Collection getMappingBasePackages() {
+        return Collections.singleton("TechVault");
+    }
+
+}

src/main/java/TechVault/services/comments/CommentService.java

@@ -0,0 +1,12 @@
+package TechVault.services.comments;
+
+import java.util.List;
+
+import TechVault.services.comments.model.CommentResponse;
+
+public interface CommentService {
+
+    public List<CommentResponse> getComments (String contentId);
+
+    public void addComment(String contentId, String parentCommentId, String userName, String comment);
+}

src/main/java/TechVault/services/comments/CommentServiceImpl.java

@@ -0,0 +1,51 @@
+package TechVault.services.comments;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+import com.google.common.base.Strings;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import TechVault.services.comments.model.Comment;
+import TechVault.services.comments.model.CommentResponse;
+import TechVault.services.comments.persistence.CommentDao;
+
+@Service
+public class CommentServiceImpl implements CommentService {
+
+    @Autowired
+    private CommentDao commentDao;
+
+    @Override
+    public List<CommentResponse> getComments(String contentId) {
+
+        List<Comment> comments = commentDao.getCommentsByBlog(contentId);
+        Map<String, CommentResponse> map = new HashMap<>();
+        List<CommentResponse> result = new ArrayList<>();
+        for (Comment comment : comments) {
+            CommentResponse commentResponse = new CommentResponse(comment);
+            if (Strings.isNullOrEmpty(comment.getParentCommentId())) {
+                result.add(commentResponse);
+            }
+            map.put(comment.getCommentId(), commentResponse);
+        }
+        for (Comment comment : comments) {
+            if (!Strings.isNullOrEmpty(comment.getParentCommentId())) {
+                CommentResponse parent = map.get(comment.getParentCommentId());
+                parent.getChildComments().add(map.get(comment.getCommentId()));
+            }
+        }
+        return result;
+    }
+
+    @Override
+    public void addComment(String contentId, String parentCommentId, String userName, String comment) {
+        commentDao.addComment(contentId, parentCommentId, userName, comment);
+    }
+
+}

src/main/java/TechVault/services/comments/controller/CommentController.java

@@ -0,0 +1,70 @@
+package TechVault.services.comments.controller;
+
+import java.util.List;
+
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.validation.annotation.Validated;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RestController;
+
+import TechVault.services.comments.CommentService;
+import TechVault.services.comments.model.CommentResponse;
+
+@Validated
+@RestController
+@RequestMapping("comment")
+public class CommentController {
+    private static final Logger LOGGER = LoggerFactory.getLogger(CommentController.class);
+
+    @Autowired
+    private CommentService commentService;
+
+    /**
+     * To the the profile of the user corresponding to the user id.
+     * @return A Response entity which will have all the user details.
+     */
+    @RequestMapping(method = RequestMethod.GET, value = "/{contentId}")
+    public ResponseEntity<?> getComments(@PathVariable String contentId) {
+        List<CommentResponse> comments = null;
+        try {
+        comments = commentService.getComments(contentId);
+        } catch (Exception e) {
+            LOGGER.error("Unable to get comments ", e);
+            return new ResponseEntity<>("ERROR", HttpStatus.INTERNAL_SERVER_ERROR);
+        }
+        return new ResponseEntity<>(comments, HttpStatus.OK);
+    }
+
+    /**
+     * To the the profile of the user corresponding to the user id.
+     * @return A Response entity which will have all the user details.
+     */
+    @RequestMapping(method = RequestMethod.POST, value = "/postComment", produces =  MediaType.APPLICATION_JSON_VALUE)
+    public ResponseEntity<?> postComment(@RequestBody String commentJson) {
+
+        JsonObject commentBody =  JsonParser.parseString(commentJson).getAsJsonObject();
+        try {
+            commentService.addComment(commentBody.get("contentId").getAsString(),
+                commentBody.get("parentCommentId").getAsString(),
+                commentBody.get("userName").getAsString(),
+                commentBody.get("comment").getAsString());
+        } catch (Exception e) {
+            LOGGER.error("Error while posting comments", e);
+            return new ResponseEntity<>("ERROR", HttpStatus.INTERNAL_SERVER_ERROR);
+        }
+        return new ResponseEntity<>("SUCCESS", HttpStatus.OK);
+    }
+
+}

src/main/java/TechVault/services/comments/model/Comment.java

@@ -0,0 +1,35 @@
+package TechVault.services.comments.model;
+
+import lombok.Builder;
+import lombok.Getter;
+import lombok.Setter;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.index.Indexed;
+import org.springframework.data.mongodb.core.mapping.Document;
+import org.springframework.data.mongodb.core.mapping.Field;
+
+@Document(collection = "comments")
+@Builder
+@Getter
+@Setter
+public class Comment {
+  @Id
+  private String commentId;
+
+  @Indexed
+  @Field(name = "contentId")
+  private String contentId;
+
+  @Field(name = "parentCommentId")
+  private String parentCommentId;
+
+  @Field(name = "userName")
+  private String userName;
+
+  @Field(name = "postedTime")
+  private String postedTime;
+
+  @Field(name = "comment")
+  private String comment;
+
+}

src/main/java/TechVault/services/comments/model/CommentResponse.java

@@ -0,0 +1,27 @@
+package TechVault.services.comments.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Data
+@AllArgsConstructor
+public class CommentResponse {
+
+    public  CommentResponse (Comment comment ) {
+        this(comment.getCommentId(), comment.getContentId(), 
+        comment.getUserName(), comment.getPostedTime(), comment.getComment(), 
+        new ArrayList<>());
+    }
+
+	private String commentId;
+    private String contentId;
+    private String userName;
+    private String postedTime;
+    private String comment;
+    private List<CommentResponse> childComments;
+}

src/main/java/TechVault/services/comments/persistence/CommentDao.java

@@ -0,0 +1,13 @@
+package TechVault.services.comments.persistence;
+
+import java.util.List;
+
+import TechVault.services.comments.model.Comment;
+
+public interface CommentDao {
+
+    public List<Comment> getCommentsByBlog(String blogUUID);
+
+    public void addComment(String contentId, String parentCommentId, String userName, String comment);
+
+}

src/main/java/TechVault/services/comments/persistence/CommentDaoImpl.java

@@ -0,0 +1,42 @@
+package TechVault.services.comments.persistence;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.List;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import TechVault.services.comments.model.Comment;
+
+
+@Component
+public class CommentDaoImpl implements CommentDao {
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(CommentDaoImpl.class);
+    private static final DateTimeFormatter formatter = DateTimeFormatter.ISO_LOCAL_DATE_TIME;
+
+    @Autowired  
+    private CommentRepository commentRepository;
+
+    @Override
+    public List<Comment> getCommentsByBlog(String contentId) {
+        return commentRepository.findByContentIdOrderByPostedTimeDesc(contentId);
+    }
+
+    @Override
+    public void addComment(String contentId, String parentCommentId, String userName, String comment) {
+        commentRepository.save(Comment.builder()
+        .parentCommentId(parentCommentId)
+        .userName(userName)
+        .contentId(contentId)
+        .comment(comment)
+        .postedTime(LocalDateTime.now().format(formatter))
+        .build());
+
+        LOGGER.info("Successfully save comment for user: {} and contentId: {}", userName, contentId);
+    }
+
+}

src/main/java/TechVault/services/comments/persistence/CommentRepository.java

@@ -0,0 +1,13 @@
+package TechVault.services.comments.persistence;
+
+import TechVault.services.comments.model.Comment;
+
+import java.util.List;
+
+import org.springframework.data.mongodb.repository.MongoRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface CommentRepository extends MongoRepository<Comment, String> {
+    public List<Comment> findByContentIdOrderByPostedTimeDesc(String contentId);
+}

src/main/resources/application.properties

@@ -1,2 +1,4 @@
 #spring.application.name: TechVault
-server.port= 8080
+server.port= 8080
+spring.data.mongodb.uri=mongodb+srv://wenqi:p@cluster0.kf3n4.mongodb.net/TechVault?retryWrites=true&w=majority
+spring.data.mongodb.database=TechVault