카톡 친구추가 API

api/src/main/kotlin/handler/FriendHandler.kt

@@ -1,7 +1,9 @@
 package com.wafflestudio.snu4t.handler
 
 import com.wafflestudio.snu4t.common.dto.ListResponse
+import com.wafflestudio.snu4t.common.dto.OkResponse
 import com.wafflestudio.snu4t.friend.dto.FriendRequest
+import com.wafflestudio.snu4t.friend.dto.FriendRequestLinkResponse
 import com.wafflestudio.snu4t.friend.dto.FriendResponse
 import com.wafflestudio.snu4t.friend.dto.FriendState
 import com.wafflestudio.snu4t.friend.dto.UpdateFriendDisplayNameRequest
@@ -75,4 +77,19 @@ class FriendHandler(
 
         friendService.breakFriend(friendId, userId)
     }
+
+    suspend fun generateFriendLink(req: ServerRequest) = handle(req) {
+        val userId = req.userId
+        val friendRequestToken = friendService.generateFriendRequestLink(userId)
+
+        FriendRequestLinkResponse(friendRequestToken)
+    }
+
+    suspend fun acceptFriendByLink(req: ServerRequest) = handle(req) {
+        val userId = req.userId
+        val requestToken = req.pathVariable("requestToken")
+
+        friendService.acceptFriendByLink(userId, requestToken)
+        OkResponse()
+    }
 }

api/src/main/kotlin/router/MainRouter.kt

@@ -199,6 +199,8 @@ class MainRouter(
             DELETE("/{friendId}", friendHandler::breakFriend)
             GET("/{friendId}/primary-table", friendTableHandler::getPrimaryTable)
             GET("/{friendId}/coursebooks", friendTableHandler::getCoursebooks)
+            GET("/generate-link", friendHandler::generateFriendLink)
+            POST("/accept-link/{requestToken}", friendHandler::acceptFriendByLink)
             GET("/{friendId}/registered-course-books", friendTableHandler::getCoursebooks) // TODO: delete
         }
     }

api/src/main/kotlin/router/docs/UserDocs.kt

@@ -1,6 +1,7 @@
 package com.wafflestudio.snu4t.router.docs
 
 import com.wafflestudio.snu4t.common.dto.OkResponse
+import com.wafflestudio.snu4t.friend.dto.FriendRequestLinkResponse
 import com.wafflestudio.snu4t.users.dto.UserDto
 import com.wafflestudio.snu4t.users.dto.UserLegacyDto
 import com.wafflestudio.snu4t.users.dto.UserPatchRequest
@@ -67,5 +68,19 @@ import org.springframework.web.bind.annotation.RequestMethod
             responses = [ApiResponse(responseCode = "200", content = [Content(schema = Schema(implementation = OkResponse::class))])]
         ),
     ),
+    RouterOperation(
+        path = "/v1/friend/generate-link", method = [RequestMethod.GET], produces = [MediaType.APPLICATION_JSON_VALUE],
+        operation = Operation(
+            operationId = "generateFriendLink",
+            responses = [ApiResponse(responseCode = "200", content = [Content(schema = Schema(implementation = FriendRequestLinkResponse::class))])]
+        ),
+    ),
+    RouterOperation(
+        path = "/v1/friend/accept-link/{requestToken}", method = [RequestMethod.POST], produces = [MediaType.APPLICATION_JSON_VALUE],
+        operation = Operation(
+            operationId = "acceptFriendByLink",
+            responses = [ApiResponse(responseCode = "200", content = [Content(schema = Schema(implementation = OkResponse::class))])]
+        ),
+    ),
 )
 annotation class UserDocs

core/src/main/kotlin/friend/dto/FriendRequestLinkResponse.kt

@@ -0,0 +1,5 @@
+package com.wafflestudio.snu4t.friend.dto
+
+data class FriendRequestLinkResponse(
+    val requestToken: String,
+)

core/src/main/kotlin/friend/service/FriendService.kt

@@ -5,6 +5,7 @@ import com.wafflestudio.snu4t.common.exception.FriendNotFoundException
 import com.wafflestudio.snu4t.common.exception.InvalidDisplayNameException
 import com.wafflestudio.snu4t.common.exception.InvalidFriendException
 import com.wafflestudio.snu4t.common.exception.UserNotFoundByNicknameException
+import com.wafflestudio.snu4t.common.exception.UserNotFoundException
 import com.wafflestudio.snu4t.common.push.DeeplinkType
 import com.wafflestudio.snu4t.common.push.dto.PushMessage
 import com.wafflestudio.snu4t.friend.data.Friend
@@ -20,8 +21,15 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.coroutineScope
 import kotlinx.coroutines.launch
+import org.springframework.data.redis.core.ReactiveStringRedisTemplate
+import org.springframework.data.redis.core.expireAndAwait
+import org.springframework.data.redis.core.getAndAwait
+import org.springframework.data.redis.core.setAndAwait
 import org.springframework.stereotype.Service
+import java.security.SecureRandom
+import java.time.Duration
 import java.time.LocalDateTime
+import java.util.Base64
 
 interface FriendService {
     suspend fun getMyFriends(myUserId: String, state: FriendState): List<Pair<Friend, User>>
@@ -37,6 +45,10 @@ interface FriendService {
     suspend fun breakFriend(friendId: String, userId: String)
 
     suspend fun get(friendId: String): Friend?
+
+    suspend fun generateFriendRequestLink(userId: String): String
+
+    suspend fun acceptFriendByLink(userId: String, requestToken: String)
 }
 
 @Service
@@ -45,6 +57,7 @@ class FriendServiceImpl(
     private val userNicknameService: UserNicknameService,
     private val friendRepository: FriendRepository,
     private val userRepository: UserRepository,
+    private val redisTemplate: ReactiveStringRedisTemplate
 ) : FriendService {
     companion object {
         private val coroutineScope = CoroutineScope(Dispatchers.Default + SupervisorJob())
@@ -148,4 +161,37 @@ class FriendServiceImpl(
     override suspend fun get(friendId: String): Friend? {
         return friendRepository.findById(friendId)
     }
+
+    override suspend fun generateFriendRequestLink(userId: String): String {
+        val bytes = ByteArray(8)
+        SecureRandom.getInstanceStrong().nextBytes(bytes)
+        val encodedKey = Base64.getUrlEncoder().withoutPadding().encodeToString(bytes)
+        val redisKey = "friend-link:$encodedKey"
+
+        redisTemplate.opsForValue().setAndAwait(redisKey, userId)
+        redisTemplate.expireAndAwait(redisKey, Duration.ofDays(14))
+        return encodedKey
+    }
+
+    override suspend fun acceptFriendByLink(userId: String, requestToken: String) {
+        val fromUserId = redisTemplate.opsForValue()
+            .getAndAwait("friend-link:$requestToken") ?: throw FriendNotFoundException
+        val fromUser = userRepository.findByIdAndActiveTrue(fromUserId) ?: throw UserNotFoundException
+        if (fromUser.id == userId)
+            throw InvalidFriendException
+        if (friendRepository.findByUserPair(fromUser.id!! to userId) != null)
+            throw DuplicateFriendException
+        val friend = friendRepository.save(
+            Friend(
+                fromUserId = fromUser.id,
+                toUserId = userId,
+                isAccepted = true,
+            )
+        )
+
+        coroutineScope.launch {
+            val toUser = requireNotNull(userRepository.findByIdAndActiveTrue(friend.toUserId))
+            sendFriendAcceptPush(friend.fromUserId, toUser)
+        }
+    }
 }