feat 🚀 AuthController 구현

#23
- Github oauth 구현을 위한 mapping 추가

BE/src/main/java/kr/codesquad/airbnb12/controller/AuthController.java

@@ -0,0 +1,37 @@
+package kr.codesquad.airbnb12.controller;
+
+import kr.codesquad.airbnb12.domain.User;
+import kr.codesquad.airbnb12.response.ApiResponse;
+import kr.codesquad.airbnb12.service.AuthService;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+import javax.servlet.http.HttpServletResponse;
+
+@RestController
+public class AuthController {
+
+    private final AuthService authService;
+
+    public AuthController(AuthService authService) {
+        this.authService = authService;
+    }
+
+    @GetMapping("/auth/github")
+    public ResponseEntity loginGithub(HttpServletResponse response) {
+        response.setHeader("Location", authService.createGithubAuthTokenUri());
+        return new ResponseEntity(HttpStatus.SEE_OTHER);
+    }
+
+    @GetMapping("/callback/github")
+    public ResponseEntity<ApiResponse<String>> githubCallback(@RequestParam("code") String code, HttpServletResponse response) {
+        String githubAccessToken = authService.getGithubAccessToken(code);
+        User user = authService.getUserInformationFromToken(githubAccessToken);
+        String jwtToken = authService.makeJwtToken(user);
+        response.setHeader("Authorization", jwtToken);
+        return new ResponseEntity<>(ApiResponse.OK("OK"), HttpStatus.OK);
+    }
+}