[4기 황창현] URL Shortener 과제 제출

build.gradle

@@ -25,6 +25,7 @@ dependencies {
     implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
     implementation 'org.springframework.boot:spring-boot-starter-thymeleaf'
     implementation 'org.springframework.boot:spring-boot-starter-web'
+    implementation 'org.springframework.boot:spring-boot-starter-validation'
     compileOnly 'org.projectlombok:lombok'
     runtimeOnly 'com.h2database:h2'
     annotationProcessor 'org.projectlombok:lombok'

src/main/java/com/programmers/urlshortener/SpringbootUrlShortenerApplication.java

@@ -2,12 +2,13 @@
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
 
 @SpringBootApplication
+@EnableJpaAuditing
 public class SpringbootUrlShortenerApplication {
 
     public static void main(String[] args) {
         SpringApplication.run(SpringbootUrlShortenerApplication.class, args);
     }
-
 }

src/main/java/com/programmers/urlshortener/common/config/WebConfig.java

@@ -0,0 +1,14 @@
+package com.programmers.urlshortener.common.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+@Configuration
+public class WebConfig implements WebMvcConfigurer {
+
+    @Override
+    public void addViewControllers(ViewControllerRegistry registry) {
+        registry.addViewController("/").setViewName("index");
+    }
+}

src/main/java/com/programmers/urlshortener/common/converter/Base62Converter.java

@@ -0,0 +1,22 @@
+package com.programmers.urlshortener.common.converter;
+
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public class Base62Converter {
+
+    private static final String ALPHABET = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    private static final int BASE = ALPHABET.length();
+
+    public static String encode(int value) {
+        StringBuilder sb = new StringBuilder();
+
+        while (value != 0) {
+            sb.append(ALPHABET.charAt(value % BASE));
+            value /= BASE;
+        }
+
+        return sb.reverse().toString();
+    }
+}

src/main/java/com/programmers/urlshortener/common/exception/BusinessException.java

@@ -0,0 +1,18 @@
+package com.programmers.urlshortener.common.exception;
+
+import org.springframework.http.HttpStatus;
+
+import lombok.Getter;
+
+@Getter
+public class BusinessException extends RuntimeException {
+
+    private HttpStatus status;
+    private String message;
+
+    protected BusinessException(ExceptionRule exceptionRule) {
+        super(exceptionRule.getMessage());
+        this.status = exceptionRule.getStatus();
+        this.message = exceptionRule.getMessage();
+    }
+}

src/main/java/com/programmers/urlshortener/common/exception/ErrorResponse.java

@@ -0,0 +1,20 @@
+package com.programmers.urlshortener.common.exception;
+
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class ErrorResponse {
+
+    private int statusCode;
+    private String message;
+
+    @Builder
+    private ErrorResponse(int statusCode, String message) {
+        this.statusCode = statusCode;
+        this.message = message;
+    }
+}

src/main/java/com/programmers/urlshortener/common/exception/ExceptionRule.java

@@ -0,0 +1,21 @@
+package com.programmers.urlshortener.common.exception;
+
+import org.springframework.http.HttpStatus;
+
+import lombok.Getter;
+import lombok.RequiredArgsConstructor;
+
+@Getter
+@RequiredArgsConstructor
+public enum ExceptionRule {
+
+    SHORTENURL_NOT_EXIST(HttpStatus.NOT_FOUND, "해당 URL은 단축된 URL 목록에서 찾을 수 없습니다."),
+    NOT_FOUND(HttpStatus.NOT_FOUND, "요청하신 URL은 없는 URL입니다."),
+    BAD_REQUEST(HttpStatus.BAD_REQUEST, "잘못된 요청입니다. 입력 값을 다시 확인해주세요."),
+    INTERNAL_SERVER_ERROR(HttpStatus.INTERNAL_SERVER_ERROR, "서버에서 알 수 없는 오류가 발생했습니다. 관리자에게 문의해주세요."),
+    URL_NOT_SAVED(HttpStatus.INTERNAL_SERVER_ERROR, "해당 URL은 데이터베이스에 저장된 URL이 아닙니다."),
+    ;
+
+    private final HttpStatus status;
+    private final String message;
+}

src/main/java/com/programmers/urlshortener/common/exception/GlobalExceptionHandler.java

@@ -0,0 +1,64 @@
+package com.programmers.urlshortener.common.exception;
+
+import static com.programmers.urlshortener.common.exception.ExceptionRule.*;
+
+import java.util.List;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.validation.FieldError;
+import org.springframework.web.bind.MethodArgumentNotValidException;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+@RestControllerAdvice
+public class GlobalExceptionHandler {
+
+    @ExceptionHandler(MethodArgumentNotValidException.class)
+    public ResponseEntity<ErrorResponse> handleMethodArgumentNotValidException(MethodArgumentNotValidException e) {
+        List<FieldError> errors = e.getBindingResult()
+            .getAllErrors()
+            .stream()
+            .map(FieldError.class::cast)
+            .toList();
+
+        log.error("[에러]: {}", e.getMessage(), e);
+
+        errors.forEach(
+            error -> log.error("메시지: {} / 원인: {} : {}", error.getDefaultMessage(), error.getField(),
+                error.getRejectedValue()));
+
+        ErrorResponse errorResponse = ErrorResponse.builder()
+            .statusCode(BAD_REQUEST.getStatus().value())
+            .message(BAD_REQUEST.getMessage())
+            .build();
+
+        return ResponseEntity.status(BAD_REQUEST.getStatus()).body(errorResponse);
+    }
+
+    @ExceptionHandler(BusinessException.class)
+    public ResponseEntity<ErrorResponse> handleBusinessException(BusinessException e) {
+        log.error("[에러]: {}", e.getMessage(), e);
+
+        ErrorResponse errorResponse = ErrorResponse.builder()
+            .statusCode(e.getStatus().value())
+            .message(e.getMessage())
+            .build();
+
+        return ResponseEntity.status(e.getStatus()).body(errorResponse);
+    }
+
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<ErrorResponse> handleException(Exception e) {
+        log.error("[에러]: {}", e.getMessage(), e);
+
+        ErrorResponse errorResponse = ErrorResponse.builder()
+            .statusCode(INTERNAL_SERVER_ERROR.getStatus().value())
+            .message(INTERNAL_SERVER_ERROR.getMessage())
+            .build();
+
+        return ResponseEntity.status(INTERNAL_SERVER_ERROR.getStatus()).body(errorResponse);
+    }
+}

src/main/java/com/programmers/urlshortener/common/exception/UrlException.java

@@ -0,0 +1,8 @@
+package com.programmers.urlshortener.common.exception;
+
+public class UrlException extends BusinessException {
+
+    public UrlException(ExceptionRule exceptionRule) {
+        super(exceptionRule);
+    }
+}

src/main/java/com/programmers/urlshortener/common/validator/UrlValidator.java

@@ -0,0 +1,23 @@
+package com.programmers.urlshortener.common.validator;
+
+import static com.programmers.urlshortener.common.exception.ExceptionRule.*;
+
+import java.util.regex.Pattern;
+
+import com.programmers.urlshortener.common.exception.UrlException;
+
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public class UrlValidator {
+
+    private static final Pattern URL_PATTERN = Pattern.compile(
+        "https?:\\/\\/(www\\.)?[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b([-a-zA-Z0-9()@:%_\\+.~#?&//=]*)");
+
+    public static void validateUrlPattern(String url) {
+        if (!URL_PATTERN.matcher(url).matches()) {
+            throw new UrlException(BAD_REQUEST);
+        }
+    }
+}

src/main/java/com/programmers/urlshortener/url/controller/RedirectController.java

@@ -0,0 +1,25 @@
+package com.programmers.urlshortener.url.controller;
+
+import java.io.IOException;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.programmers.urlshortener.url.service.UrlService;
+
+import jakarta.servlet.http.HttpServletResponse;
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequiredArgsConstructor
+public class RedirectController {
+
+    private final UrlService urlService;
+
+    @GetMapping("/{shortUrl}")
+    public void redirectOriginUrl(@PathVariable String shortUrl, HttpServletResponse response) throws IOException {
+        String originalUrl = urlService.findOriginalUrlByShortUrl(shortUrl);
+        response.sendRedirect(originalUrl);
+    }
+}

src/main/java/com/programmers/urlshortener/url/controller/UrlController.java

@@ -0,0 +1,41 @@
+package com.programmers.urlshortener.url.controller;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.programmers.urlshortener.url.dto.request.ShortUrlCreateRequest;
+import com.programmers.urlshortener.url.dto.response.UrlResponse;
+import com.programmers.urlshortener.url.service.UrlService;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.validation.Valid;
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequiredArgsConstructor
+@RequestMapping("/urls")
+public class UrlController {
+
+    private final UrlService urlService;
+
+    @PostMapping
+    public ResponseEntity<UrlResponse> createShortUrl(@Valid @RequestBody ShortUrlCreateRequest shortUrlCreateRequest,
+        HttpServletRequest httpServletRequest) {
+        UrlResponse urlResponse = urlService.createShortUrl(shortUrlCreateRequest, httpServletRequest.getRemoteAddr());
+
+        return ResponseEntity.status(HttpStatus.CREATED).body(urlResponse);
+    }
+
+    @GetMapping("/{shortUrl}")
+    public ResponseEntity<UrlResponse> getShortUrlInfo(@PathVariable String shortUrl) {
+        UrlResponse urlResponse = urlService.findUrlByShortUrl(shortUrl);
+
+        return ResponseEntity.ok(urlResponse);
+    }
+}

src/main/java/com/programmers/urlshortener/url/domain/Algorithm.java

@@ -0,0 +1,13 @@
+package com.programmers.urlshortener.url.domain;
+
+import com.programmers.urlshortener.common.converter.Base62Converter;
+
+public enum Algorithm {
+    BASE62 {
+        public String getShortUrl(int num) {
+            return Base62Converter.encode(num);
+        }
+    };
+
+    public abstract String getShortUrl(int num);
+}

src/main/java/com/programmers/urlshortener/url/domain/Url.java

@@ -0,0 +1,80 @@
+package com.programmers.urlshortener.url.domain;
+
+import static com.programmers.urlshortener.common.exception.ExceptionRule.*;
+import static com.programmers.urlshortener.common.validator.UrlValidator.*;
+
+import java.time.LocalDateTime;
+
+import org.hibernate.annotations.ColumnDefault;
+import org.hibernate.annotations.DynamicInsert;
+import org.hibernate.annotations.DynamicUpdate;
+import org.springframework.data.annotation.CreatedDate;
+import org.springframework.data.jpa.domain.support.AuditingEntityListener;
+
+import com.programmers.urlshortener.common.exception.UrlException;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.Entity;
+import jakarta.persistence.EntityListeners;
+import jakarta.persistence.EnumType;
+import jakarta.persistence.Enumerated;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import lombok.AccessLevel;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Getter
+@DynamicInsert
+@DynamicUpdate
+@EntityListeners(AuditingEntityListener.class)
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class Url {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Enumerated(EnumType.STRING)
+    private Algorithm algorithm;
+
+    @Column(nullable = false)
+    private String originalUrl;
+
+    @Column(unique = true)
+    private String shortUrl;
+
+    @Column(nullable = false)
+    private String ip;
+
+    @CreatedDate
+    @Column(columnDefinition = "TIMESTAMP", nullable = false, updatable = false)
+    private LocalDateTime createdAt;
+
+    @Column(nullable = false)
+    @ColumnDefault("0")
+    private Long viewCount;
+
+    @Builder
+    public Url(String originalUrl, Algorithm algorithm, String ip) {
+        validateUrlPattern(originalUrl);
+        this.algorithm = algorithm;
+        this.originalUrl = originalUrl;
+        this.ip = ip;
+    }
+
+    public void convertToShortUrl() {
+        if (id == null) {
+            throw new UrlException(URL_NOT_SAVED);
+        }
+
+        this.shortUrl = algorithm.getShortUrl(id.intValue());
+    }
+
+    public void increaseCount() {
+        viewCount += 1;
+    }
+}