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/login/application/GithubClient.java

@@ -0,0 +1,68 @@
+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 {
+
+  @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 = new GithubAccessTokenRequest(
+        code,
+        clientId,
+        clientSecret
+    );
+
+    final HttpHeaders headers = new HttpHeaders();
+    headers.add("Accept", MediaType.APPLICATION_JSON_VALUE);
+
+    final HttpEntity httpEntity = new HttpEntity(githubAccessTokenRequest, headers);
+    final RestTemplate restTemplate = new RestTemplate();
+
+    final String accessToken = restTemplate
+        .exchange(accessTokenUrl, HttpMethod.POST, httpEntity, GithubAccessTokenResponse.class)
+        .getBody()
+        .getAccessToken();
+
+    if (accessToken == null) {
+      throw new LoginException(LoginExceptionType.NOT_FOUND_GITHUB_ACCESS_TOKEN);
+    }
+    return accessToken;
+  }
+
+  public GithubProfileResponse getGithubProfileFromGithub(final String accessToken) {
+    final HttpHeaders headers = new HttpHeaders();
+    headers.add("Authorization", "token " + accessToken);
+
+    final HttpEntity httpEntity = new HttpEntity(headers);
+    final RestTemplate restTemplate = new RestTemplate();
+
+    try {
+      return restTemplate
+          .exchange(profileUrl, HttpMethod.GET, httpEntity, GithubProfileResponse.class)
+          .getBody();
+    } catch (final HttpClientErrorException e) {
+      throw new LoginException(LoginExceptionType.INVALID_GITHUB_ACCESS_TOKEN);
+    }
+  }
+}

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

@@ -0,0 +1,30 @@
+package com.emmsale.login.application;
+
+import io.jsonwebtoken.Claims;
+import io.jsonwebtoken.Jwts;
+import io.jsonwebtoken.SignatureAlgorithm;
+import java.util.Date;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+@Component
+public class JwtTokenProvider {
+
+  @Value("${security.jwt.token.secret-key}")
+  private String secretKey;
+  @Value("${security.jwt.token.expire-length}")
+  private long additionalValidityMillisecond;
+
+  public String createToken(final String memberId) {
+    final Claims claims = Jwts.claims().setSubject(memberId);
+    final Date now = new Date();
+    final Date expirationTime = new Date(now.getTime() + additionalValidityMillisecond);
+
+    return Jwts.builder()
+        .setClaims(claims)
+        .setIssuedAt(now)
+        .setExpiration(expirationTime)
+        .signWith(SignatureAlgorithm.HS256, secretKey)
+        .compact();
+  }
+}

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

@@ -0,0 +1,30 @@
+package com.emmsale.login.application;
+
+import com.emmsale.login.application.dto.GithubProfileResponse;
+import com.emmsale.login.application.dto.TokenResponse;
+import org.springframework.stereotype.Service;
+
+@Service
+public class LoginService {
+
+  private final GithubClient githubClient;
+  private final JwtTokenProvider tokenProvider;
+
+  public LoginService(final GithubClient githubClient, final JwtTokenProvider tokenProvider) {
+    this.githubClient = githubClient;
+    this.tokenProvider = tokenProvider;
+  }
+
+  public TokenResponse createToken(final String code) {
+    final String githubAccessToken = githubClient.getAccessTokenFromGithub(code);
+    final GithubProfileResponse githubProfileFromGithub = githubClient.getGithubProfileFromGithub(
+        githubAccessToken);
+
+    final Long githubId = githubProfileFromGithub.getGithubId();
+    //TODO: githubId를 통해 memberId 조회 기능 구현
+    final Long memberId = 1L;
+    final String accessToken = tokenProvider.createToken(memberId.toString());
+
+    return new TokenResponse(memberId, 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;
+
+@AllArgsConstructor
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@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 +1,26 @@
+package com.emmsale.login.application.dto;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@AllArgsConstructor
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@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);
+  }
+}

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

@@ -0,0 +1,15 @@
+package com.emmsale.login.application.dto;
+
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@AllArgsConstructor
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@Getter
+public class TokenResponse {
+
+  private Long memberId;
+  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 +1,34 @@
+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."
+  );
+
+  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/ui/LoginController.java

@@ -0,0 +1,28 @@
+package com.emmsale.login.ui;
+
+import com.emmsale.login.application.LoginService;
+import com.emmsale.login.application.dto.TokenResponse;
+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 LoginController {
+
+  private final LoginService loginService;
+
+  public LoginController(final LoginService loginService) {
+    this.loginService = loginService;
+  }
+
+  @GetMapping("/github/callback")
+  public ResponseEntity<TokenResponse> login(@RequestParam final String code) {
+    if (code == null) {
+      return ResponseEntity.badRequest().build();
+    }
+    return ResponseEntity.ok().body(loginService.createToken(code));
+  }
+}

backend/emm-sale/src/main/resources/application.yml

@@ -24,3 +24,17 @@ logging:
           descriptor:
             sql:
               BasicBinder: TRACE
+
+github:
+  client:
+    id: client_id
+    secret: client_secret
+  url:
+    access-token: access-token_url
+    profile: profile_url
+
+security:
+  jwt:
+    token:
+      secret-key: secret_key
+      expire-length: 3_600_000_000