Feature/#41 깃허브 로그인 기능 구현

backend/emm-sale/build.gradle

@@ -62,6 +62,9 @@ dependencies {
     testImplementation 'org.springframework.boot:spring-boot-starter-test'
     testImplementation 'org.springframework.restdocs:spring-restdocs-mockmvc'
     asciidoctorExt 'org.springframework.restdocs:spring-restdocs-asciidoctor'
+
+    // jwt
+    implementation 'io.jsonwebtoken:jjwt:0.9.1'
 }
 
 tasks.named('test') {

backend/emm-sale/src/main/java/com/emmsale/config/ArgumentResolverConfig.java

@@ -1,6 +1,5 @@
 package com.emmsale.config;
 
-import com.emmsale.member.application.MemberQueryService;
 import com.emmsale.resolver.MemberArgumentResolver;
 import java.util.List;
 import lombok.RequiredArgsConstructor;
@@ -12,10 +11,10 @@
 @RequiredArgsConstructor
 public class ArgumentResolverConfig implements WebMvcConfigurer {
 
-  private final MemberQueryService memberQueryService;
+  private final MemberArgumentResolver memberArgumentResolver;
 
   @Override
   public void addArgumentResolvers(final List<HandlerMethodArgumentResolver> resolvers) {
-    resolvers.add(new MemberArgumentResolver(memberQueryService));
+    resolvers.add(memberArgumentResolver);
   }
 }

backend/emm-sale/src/main/java/com/emmsale/login/api/LoginApi.java

@@ -0,0 +1,30 @@
+package com.emmsale.login.api;
+
+import com.emmsale.login.application.LoginService;
+import com.emmsale.login.application.dto.TokenResponse;
+import com.emmsale.login.exception.LoginException;
+import com.emmsale.login.exception.LoginExceptionType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/login")
+public class LoginApi {
+
+  private final LoginService loginService;
+
+  public LoginApi(final LoginService loginService) {
+    this.loginService = loginService;
+  }
+
+  @GetMapping("/github/callback")
+  public ResponseEntity<TokenResponse> login(@RequestParam final String code) {
+    if (code == null) {
+      throw new LoginException(LoginExceptionType.NOT_FOUND_GITHUB_CODE);
+    }
+    return ResponseEntity.ok().body(loginService.createToken(code));
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/GithubClient.java

@@ -0,0 +1,90 @@
+package com.emmsale.login.application;
+
+import com.emmsale.login.application.dto.GithubAccessTokenRequest;
+import com.emmsale.login.application.dto.GithubAccessTokenResponse;
+import com.emmsale.login.application.dto.GithubProfileResponse;
+import com.emmsale.login.exception.LoginException;
+import com.emmsale.login.exception.LoginExceptionType;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestTemplate;
+
+@Component
+public class GithubClient {
+
+  private static final RestTemplate REST_TEMPLATE = new RestTemplate();
+
+  @Value("${github.client.id}")
+  private String clientId;
+  @Value("${github.client.secret}")
+  private String clientSecret;
+  @Value("${github.url.access-token}")
+  private String accessTokenUrl;
+  @Value("${github.url.profile}")
+  private String profileUrl;
+
+  public String getAccessTokenFromGithub(final String code) {
+    final GithubAccessTokenRequest githubAccessTokenRequest = buildGithubAccessTokenRequest(code);
+
+    try {
+      final String accessToken = getAccessTokenResponse(githubAccessTokenRequest);
+      throwIfNotFoundAccessToken(accessToken);
+      return accessToken;
+    } catch (final HttpClientErrorException httpClientErrorException) {
+      throw new LoginException(LoginExceptionType.INVALID_GITHUB_CODE);
+    }
+  }
+
+  public GithubProfileResponse getGithubProfileFromGithub(final String accessToken) {
+    try {
+      return getGithubProfileResponse(accessToken);
+    } catch (final HttpClientErrorException httpClientErrorException) {
+      throw new LoginException(LoginExceptionType.INVALID_GITHUB_ACCESS_TOKEN);
+    }
+  }
+
+  private GithubProfileResponse getGithubProfileResponse(final String accessToken) {
+    final HttpHeaders headers = new HttpHeaders();
+    headers.add(HttpHeaders.AUTHORIZATION, "token " + accessToken);
+
+    final HttpEntity<String> httpEntity = new HttpEntity<>(headers);
+
+    return REST_TEMPLATE
+        .exchange(profileUrl, HttpMethod.GET, httpEntity, GithubProfileResponse.class)
+        .getBody();
+  }
+
+  private GithubAccessTokenRequest buildGithubAccessTokenRequest(final String code) {
+    return new GithubAccessTokenRequest(
+        code,
+        clientId,
+        clientSecret
+    );
+  }
+
+  private String getAccessTokenResponse(final GithubAccessTokenRequest githubAccessTokenRequest) {
+    final HttpHeaders headers = new HttpHeaders();
+    headers.add(HttpHeaders.ACCEPT, MediaType.APPLICATION_JSON_VALUE);
+
+    final HttpEntity<GithubAccessTokenRequest> httpEntity = new HttpEntity<>(
+        githubAccessTokenRequest,
+        headers
+    );
+
+    return REST_TEMPLATE
+        .exchange(accessTokenUrl, HttpMethod.POST, httpEntity, GithubAccessTokenResponse.class)
+        .getBody()
+        .getAccessToken();
+  }
+
+  private void throwIfNotFoundAccessToken(final String accessToken) {
+    if (accessToken == null || accessToken.isBlank()) {
+      throw new LoginException(LoginExceptionType.NOT_FOUND_GITHUB_ACCESS_TOKEN);
+    }
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/LoginService.java

@@ -0,0 +1,45 @@
+package com.emmsale.login.application;
+
+import com.emmsale.login.application.dto.GithubProfileResponse;
+import com.emmsale.login.application.dto.MemberQueryResponse;
+import com.emmsale.login.application.dto.TokenResponse;
+import com.emmsale.login.utils.JwtTokenProvider;
+import com.emmsale.member.application.MemberQueryService;
+import org.springframework.stereotype.Service;
+
+@Service
+public class LoginService {
+
+  private final GithubClient githubClient;
+  private final JwtTokenProvider tokenProvider;
+  private final MemberQueryService memberQueryService;
+
+  public LoginService(
+      final GithubClient githubClient,
+      final JwtTokenProvider tokenProvider,
+      final MemberQueryService memberQueryService
+  ) {
+    this.githubClient = githubClient;
+    this.tokenProvider = tokenProvider;
+    this.memberQueryService = memberQueryService;
+  }
+
+  public TokenResponse createToken(final String code) {
+    final String githubAccessToken = githubClient.getAccessTokenFromGithub(code);
+    final GithubProfileResponse githubProfileFromGithub = githubClient.getGithubProfileFromGithub(
+        githubAccessToken);
+
+    final MemberQueryResponse memberQueryResponse = memberQueryService.findOrCreateMember(
+        githubProfileFromGithub
+    );
+    final String accessToken = tokenProvider.createToken(
+        String.valueOf(memberQueryResponse.getMemberId())
+    );
+
+    return new TokenResponse(
+        memberQueryResponse.getMemberId(),
+        memberQueryResponse.isNewMember(),
+        accessToken
+    );
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/dto/GithubAccessTokenRequest.java

@@ -0,0 +1,16 @@
+package com.emmsale.login.application.dto;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@AllArgsConstructor
+@Getter
+public class GithubAccessTokenRequest {
+
+  private final String code;
+  @JsonProperty("client_id")
+  private final String clientId;
+  @JsonProperty("client_secret")
+  private final String clientSecret;
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/dto/GithubAccessTokenResponse.java

@@ -0,0 +1,20 @@
+package com.emmsale.login.application.dto;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Getter
+public class GithubAccessTokenResponse {
+
+  @JsonProperty("access_token")
+  private String accessToken;
+  @JsonProperty("token_type")
+  private String tokenType;
+  private String scope;
+  private String bearer;
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/dto/GithubProfileResponse.java

@@ -0,0 +1,34 @@
+package com.emmsale.login.application.dto;
+
+import com.emmsale.member.domain.Member;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor
+@Getter
+public class GithubProfileResponse {
+
+  @JsonProperty("id")
+  private String githubId;
+  @JsonProperty("name")
+  private String name;
+  @JsonProperty("login")
+  private String username;
+  @JsonProperty("avatar_url")
+  private String imageUrl;
+
+  public Long getGithubId() {
+    return Long.valueOf(githubId);
+  }
+
+  public Member toMember() {
+    return new Member(
+        getGithubId(),
+        getUsername()
+    );
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/dto/MemberQueryResponse.java

@@ -0,0 +1,12 @@
+package com.emmsale.login.application.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@AllArgsConstructor
+@Getter
+public class MemberQueryResponse {
+
+  private long memberId;
+  private boolean isNewMember;
+}

backend/emm-sale/src/main/java/com/emmsale/login/application/dto/TokenResponse.java

@@ -0,0 +1,13 @@
+package com.emmsale.login.application.dto;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@AllArgsConstructor
+@Getter
+public class TokenResponse {
+
+  private long memberId;
+  private boolean isNewMember;
+  private String accessToken;
+}

backend/emm-sale/src/main/java/com/emmsale/login/exception/LoginException.java

@@ -0,0 +1,19 @@
+package com.emmsale.login.exception;
+
+import com.emmsale.base.BaseException;
+import com.emmsale.base.BaseExceptionType;
+
+public class LoginException extends BaseException {
+
+  private final LoginExceptionType exceptionType;
+
+  public LoginException(final LoginExceptionType exceptionType) {
+    super(exceptionType.errorMessage());
+    this.exceptionType = exceptionType;
+  }
+
+  @Override
+  public BaseExceptionType exceptionType() {
+    return exceptionType;
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/exception/LoginExceptionType.java

@@ -0,0 +1,50 @@
+package com.emmsale.login.exception;
+
+import com.emmsale.base.BaseExceptionType;
+import org.springframework.http.HttpStatus;
+
+public enum LoginExceptionType implements BaseExceptionType {
+
+  NOT_FOUND_GITHUB_ACCESS_TOKEN(
+      HttpStatus.BAD_REQUEST,
+      "GitHub Access Token을 찾을 수 없습니다."
+  ),
+  INVALID_GITHUB_ACCESS_TOKEN(
+      HttpStatus.NOT_FOUND,
+      "GitHub Profile을 찾을 수 없습니다."
+  ),
+  INVALID_ACCESS_TOKEN(
+      HttpStatus.BAD_REQUEST,
+      "토큰이 유효하지 않습니다."
+  ),
+  NOT_FOUND_AUTHORIZATION_TOKEN(
+      HttpStatus.BAD_REQUEST,
+      "인증 토큰을 찾을 수 없습니다."
+  ),
+  NOT_FOUND_GITHUB_CODE(
+      HttpStatus.BAD_REQUEST,
+      "깃허브 코드를 찾을 수 없습니다."
+  ),
+  INVALID_GITHUB_CODE(
+      HttpStatus.BAD_REQUEST,
+      "깃허브 코드가 유효하지 않습니다."
+  );
+
+  private final HttpStatus httpStatus;
+  private final String errorMessage;
+
+  LoginExceptionType(final HttpStatus httpStatus, final String errorMessage) {
+    this.httpStatus = httpStatus;
+    this.errorMessage = errorMessage;
+  }
+
+  @Override
+  public HttpStatus httpStatus() {
+    return httpStatus;
+  }
+
+  @Override
+  public String errorMessage() {
+    return errorMessage;
+  }
+}

backend/emm-sale/src/main/java/com/emmsale/login/utils/AuthorizationExtractor.java

@@ -0,0 +1,27 @@
+package com.emmsale.login.utils;
+
+import javax.servlet.http.HttpServletRequest;
+import org.springframework.http.HttpHeaders;
+
+public class AuthorizationExtractor {
+
+  private static final String ACCESS_TOKEN_TYPE =
+      AuthorizationExtractor.class.getSimpleName() + ".ACCESS_TOKEN_TYPE";
+  private static final String BEARER_TYPE = "Bearer";
+
+  public static String extract(final HttpServletRequest request) {
+    String authHeaderValue = request.getHeader(HttpHeaders.AUTHORIZATION)
+        .substring(BEARER_TYPE.length()).trim();
+
+    if (authHeaderValue.isBlank()) {
+      return null;
+    }
+
+    request.setAttribute(ACCESS_TOKEN_TYPE, BEARER_TYPE);
+    final int commaIndex = authHeaderValue.indexOf(',');
+    if (commaIndex > 0) {
+      authHeaderValue = authHeaderValue.substring(0, commaIndex);
+    }
+    return authHeaderValue;
+  }
+}