android: add minimum invite link join flow

android/CHANGELOG.md

@@ -130,3 +130,9 @@
 - Added `ObserveChatUseCase` to expose per-chat permission state to message screen.
 - Implemented channel send restrictions in `ChatViewModel`: sending/attach disabled for `member` role in `channel` chats.
 - Added composer-level restriction hint in Chat UI to explain blocked actions.
+
+### Step 21 - Sprint P0 / 4) Invite join flow (minimum)
+- Added chat API contracts for invite actions: `POST /api/v1/chats/{chat_id}/invite-link` and `POST /api/v1/chats/join-by-invite`.
+- Added domain model/use-cases for invite-link creation and join-by-invite.
+- Extended chat repository with invite operations and local chat upsert on successful join.
+- Added minimal Chat List UI flow for join-by-invite token input with loading/error handling and auto-open of joined chat.

android/app/src/main/java/ru/daemonlord/messenger/data/chat/api/ChatApiService.kt

@@ -1,8 +1,12 @@
 package ru.daemonlord.messenger.data.chat.api
 
+import retrofit2.http.Body
 import retrofit2.http.GET
 import retrofit2.http.Path
+import retrofit2.http.POST
 import retrofit2.http.Query
+import ru.daemonlord.messenger.data.chat.dto.ChatInviteLinkDto
+import ru.daemonlord.messenger.data.chat.dto.ChatJoinByInviteRequestDto
 import ru.daemonlord.messenger.data.chat.dto.ChatReadDto
 
 interface ChatApiService {
@@ -15,4 +19,14 @@ interface ChatApiService {
     suspend fun getChatById(
         @Path("chat_id") chatId: Long,
     ): ChatReadDto
+
+    @POST("/api/v1/chats/{chat_id}/invite-link")
+    suspend fun createInviteLink(
+        @Path("chat_id") chatId: Long,
+    ): ChatInviteLinkDto
+
+    @POST("/api/v1/chats/join-by-invite")
+    suspend fun joinByInvite(
+        @Body request: ChatJoinByInviteRequestDto,
+    ): ChatReadDto
 }

android/app/src/main/java/ru/daemonlord/messenger/data/chat/dto/ChatDtos.kt

@@ -45,3 +45,17 @@ data class ChatReadDto(
     @SerialName("created_at")
     val createdAt: String? = null,
 )
+
+@Serializable
+data class ChatInviteLinkDto(
+    @SerialName("chat_id")
+    val chatId: Long,
+    val token: String,
+    @SerialName("invite_url")
+    val inviteUrl: String,
+)
+
+@Serializable
+data class ChatJoinByInviteRequestDto(
+    val token: String,
+)

android/app/src/main/java/ru/daemonlord/messenger/data/chat/mapper/ChatLocalMapper.kt

@@ -1,6 +1,7 @@
 package ru.daemonlord.messenger.data.chat.mapper
 
 import ru.daemonlord.messenger.data.chat.local.model.ChatListLocalModel
+import ru.daemonlord.messenger.data.chat.local.entity.ChatEntity
 import ru.daemonlord.messenger.domain.chat.model.ChatItem
 
 fun ChatListLocalModel.toDomain(): ChatItem {
@@ -29,3 +30,30 @@ fun ChatListLocalModel.toDomain(): ChatItem {
         updatedSortAt = updatedSortAt,
     )
 }
+
+fun ChatEntity.toDomain(): ChatItem {
+    return ChatItem(
+        id = id,
+        publicId = publicId,
+        type = type,
+        title = title,
+        displayTitle = displayTitle,
+        handle = handle,
+        avatarUrl = avatarUrl,
+        archived = archived,
+        pinned = pinned,
+        muted = muted,
+        unreadCount = unreadCount,
+        unreadMentionsCount = unreadMentionsCount,
+        counterpartUsername = counterpartUsername,
+        counterpartName = counterpartName,
+        counterpartAvatarUrl = counterpartAvatarUrl,
+        counterpartIsOnline = counterpartIsOnline,
+        counterpartLastSeenAt = counterpartLastSeenAt,
+        lastMessageText = lastMessageText,
+        lastMessageType = lastMessageType,
+        lastMessageCreatedAt = lastMessageCreatedAt,
+        myRole = myRole,
+        updatedSortAt = updatedSortAt,
+    )
+}

android/app/src/main/java/ru/daemonlord/messenger/data/chat/mapper/ChatRemoteMapper.kt

@@ -1,8 +1,10 @@
 package ru.daemonlord.messenger.data.chat.mapper
 
 import ru.daemonlord.messenger.data.chat.dto.ChatReadDto
+import ru.daemonlord.messenger.data.chat.dto.ChatInviteLinkDto
 import ru.daemonlord.messenger.data.chat.local.entity.ChatEntity
 import ru.daemonlord.messenger.data.chat.local.entity.UserShortEntity
+import ru.daemonlord.messenger.domain.chat.model.ChatInviteLink
 
 fun ChatReadDto.toChatEntity(): ChatEntity {
     return ChatEntity(
@@ -42,3 +44,11 @@ fun ChatReadDto.toUserShortEntityOrNull(): UserShortEntity? {
         avatarUrl = counterpartAvatarUrl,
     )
 }
+
+fun ChatInviteLinkDto.toDomain(): ChatInviteLink {
+    return ChatInviteLink(
+        chatId = chatId,
+        token = token,
+        inviteUrl = inviteUrl,
+    )
+}

android/app/src/main/java/ru/daemonlord/messenger/data/chat/repository/NetworkChatRepository.kt

@@ -10,10 +10,12 @@ import kotlinx.coroutines.launch
 import kotlinx.coroutines.channels.awaitClose
 import retrofit2.HttpException
 import ru.daemonlord.messenger.data.chat.api.ChatApiService
+import ru.daemonlord.messenger.data.chat.dto.ChatJoinByInviteRequestDto
 import ru.daemonlord.messenger.data.chat.local.dao.ChatDao
 import ru.daemonlord.messenger.data.chat.mapper.toChatEntity
 import ru.daemonlord.messenger.data.chat.mapper.toDomain
 import ru.daemonlord.messenger.data.chat.mapper.toUserShortEntityOrNull
+import ru.daemonlord.messenger.domain.chat.model.ChatInviteLink
 import ru.daemonlord.messenger.di.IoDispatcher
 import ru.daemonlord.messenger.domain.chat.model.ChatItem
 import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
@@ -75,6 +77,26 @@ class NetworkChatRepository @Inject constructor(
         }
     }
 
+    override suspend fun createInviteLink(chatId: Long): AppResult<ChatInviteLink> = withContext(ioDispatcher) {
+        try {
+            AppResult.Success(chatApiService.createInviteLink(chatId = chatId).toDomain())
+        } catch (error: Throwable) {
+            AppResult.Error(error.toAppError())
+        }
+    }
+
+    override suspend fun joinByInvite(token: String): AppResult<ChatItem> = withContext(ioDispatcher) {
+        try {
+            val joined = chatApiService.joinByInvite(request = ChatJoinByInviteRequestDto(token = token))
+            chatDao.upsertUsers(joined.toUserShortEntityOrNull()?.let(::listOf).orEmpty())
+            val chatEntity = joined.toChatEntity()
+            chatDao.upsertChats(listOf(chatEntity))
+            AppResult.Success(chatEntity.toDomain())
+        } catch (error: Throwable) {
+            AppResult.Error(error.toAppError())
+        }
+    }
+
     override suspend fun deleteChat(chatId: Long) {
         withContext(ioDispatcher) {
             chatDao.deleteChat(chatId = chatId)

android/app/src/main/java/ru/daemonlord/messenger/domain/chat/model/ChatInviteLink.kt

@@ -0,0 +1,7 @@
+package ru.daemonlord.messenger.domain.chat.model
+
+data class ChatInviteLink(
+    val chatId: Long,
+    val token: String,
+    val inviteUrl: String,
+)

android/app/src/main/java/ru/daemonlord/messenger/domain/chat/repository/ChatRepository.kt

@@ -1,6 +1,7 @@
 package ru.daemonlord.messenger.domain.chat.repository
 
 import kotlinx.coroutines.flow.Flow
+import ru.daemonlord.messenger.domain.chat.model.ChatInviteLink
 import ru.daemonlord.messenger.domain.chat.model.ChatItem
 import ru.daemonlord.messenger.domain.common.AppResult
 
@@ -9,5 +10,7 @@ interface ChatRepository {
     fun observeChat(chatId: Long): Flow<ChatItem?>
     suspend fun refreshChats(archived: Boolean): AppResult<Unit>
     suspend fun refreshChat(chatId: Long): AppResult<Unit>
+    suspend fun createInviteLink(chatId: Long): AppResult<ChatInviteLink>
+    suspend fun joinByInvite(token: String): AppResult<ChatItem>
     suspend fun deleteChat(chatId: Long)
 }

android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/CreateInviteLinkUseCase.kt

@@ -0,0 +1,14 @@
+package ru.daemonlord.messenger.domain.chat.usecase
+
+import ru.daemonlord.messenger.domain.chat.model.ChatInviteLink
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
+import ru.daemonlord.messenger.domain.common.AppResult
+import javax.inject.Inject
+
+class CreateInviteLinkUseCase @Inject constructor(
+    private val repository: ChatRepository,
+) {
+    suspend operator fun invoke(chatId: Long): AppResult<ChatInviteLink> {
+        return repository.createInviteLink(chatId = chatId)
+    }
+}

android/app/src/main/java/ru/daemonlord/messenger/domain/chat/usecase/JoinByInviteUseCase.kt

@@ -0,0 +1,14 @@
+package ru.daemonlord.messenger.domain.chat.usecase
+
+import ru.daemonlord.messenger.domain.chat.model.ChatItem
+import ru.daemonlord.messenger.domain.chat.repository.ChatRepository
+import ru.daemonlord.messenger.domain.common.AppResult
+import javax.inject.Inject
+
+class JoinByInviteUseCase @Inject constructor(
+    private val repository: ChatRepository,
+) {
+    suspend operator fun invoke(token: String): AppResult<ChatItem> {
+        return repository.joinByInvite(token = token)
+    }
+}

android/app/src/main/java/ru/daemonlord/messenger/ui/chats/ChatListScreen.kt

@@ -12,6 +12,7 @@ import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
 import androidx.compose.material3.AssistChip
 import androidx.compose.material3.AssistChipDefaults
+import androidx.compose.material3.Button
 import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.MaterialTheme
@@ -21,6 +22,7 @@ import androidx.compose.material3.TabRow
 import androidx.compose.material3.Text
 import androidx.compose.material3.pulltorefresh.PullToRefreshBox
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
@@ -36,10 +38,17 @@ fun ChatListRoute(
     viewModel: ChatListViewModel = hiltViewModel(),
 ) {
     val state by viewModel.uiState.collectAsStateWithLifecycle()
+    LaunchedEffect(state.pendingOpenChatId) {
+        val chatId = state.pendingOpenChatId ?: return@LaunchedEffect
+        onOpenChat(chatId)
+        viewModel.onNavigatedToPendingChat()
+    }
     ChatListScreen(
         state = state,
         onTabSelected = viewModel::onTabSelected,
         onSearchChanged = viewModel::onSearchChanged,
+        onInviteTokenChanged = viewModel::onInviteTokenChanged,
+        onJoinByInvite = viewModel::onJoinByInvite,
         onRefresh = viewModel::onPullToRefresh,
         onOpenChat = onOpenChat,
     )
@@ -51,6 +60,8 @@ fun ChatListScreen(
     state: ChatListUiState,
     onTabSelected: (ChatTab) -> Unit,
     onSearchChanged: (String) -> Unit,
+    onInviteTokenChanged: (String) -> Unit,
+    onJoinByInvite: () -> Unit,
     onRefresh: () -> Unit,
     onOpenChat: (Long) -> Unit,
 ) {
@@ -82,6 +93,28 @@ fun ChatListScreen(
                 .padding(horizontal = 16.dp, vertical = 8.dp),
         )
 
+        Row(
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(horizontal = 16.dp, vertical = 4.dp),
+            horizontalArrangement = Arrangement.spacedBy(8.dp),
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            OutlinedTextField(
+                value = state.inviteTokenInput,
+                onValueChange = onInviteTokenChanged,
+                label = { Text("Invite token") },
+                singleLine = true,
+                modifier = Modifier.weight(1f),
+            )
+            Button(
+                onClick = onJoinByInvite,
+                enabled = !state.isJoiningInvite && state.inviteTokenInput.isNotBlank(),
+            ) {
+                Text(if (state.isJoiningInvite) "..." else "Join")
+            }
+        }
+
         PullToRefreshBox(
             isRefreshing = state.isRefreshing,
             onRefresh = onRefresh,

android/app/src/main/java/ru/daemonlord/messenger/ui/chats/ChatListUiState.kt

@@ -9,4 +9,7 @@ data class ChatListUiState(
     val isRefreshing: Boolean = false,
     val errorMessage: String? = null,
     val chats: List<ChatItem> = emptyList(),
+    val inviteTokenInput: String = "",
+    val isJoiningInvite: Boolean = false,
+    val pendingOpenChatId: Long? = null,
 )

android/app/src/main/java/ru/daemonlord/messenger/ui/chats/ChatListViewModel.kt

@@ -12,6 +12,7 @@ import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import ru.daemonlord.messenger.domain.chat.model.ChatItem
+import ru.daemonlord.messenger.domain.chat.usecase.JoinByInviteUseCase
 import ru.daemonlord.messenger.domain.chat.usecase.ObserveChatsUseCase
 import ru.daemonlord.messenger.domain.chat.usecase.RefreshChatsUseCase
 import ru.daemonlord.messenger.domain.common.AppError
@@ -23,6 +24,7 @@ import javax.inject.Inject
 class ChatListViewModel @Inject constructor(
     private val observeChatsUseCase: ObserveChatsUseCase,
     private val refreshChatsUseCase: RefreshChatsUseCase,
+    private val joinByInviteUseCase: JoinByInviteUseCase,
     private val handleRealtimeEventsUseCase: HandleRealtimeEventsUseCase,
 ) : ViewModel() {
 
@@ -52,6 +54,42 @@ class ChatListViewModel @Inject constructor(
         refreshCurrentTab(forceRefresh = true)
     }
 
+    fun onInviteTokenChanged(value: String) {
+        _uiState.update { it.copy(inviteTokenInput = value) }
+    }
+
+    fun onJoinByInvite() {
+        val token = uiState.value.inviteTokenInput.trim()
+        if (token.isBlank()) return
+        viewModelScope.launch {
+            _uiState.update { it.copy(isJoiningInvite = true, errorMessage = null) }
+            when (val result = joinByInviteUseCase(token = token)) {
+                is AppResult.Success -> {
+                    _uiState.update {
+                        it.copy(
+                            isJoiningInvite = false,
+                            inviteTokenInput = "",
+                            pendingOpenChatId = result.data.id,
+                        )
+                    }
+                    refreshCurrentTab(forceRefresh = true)
+                }
+                is AppResult.Error -> {
+                    _uiState.update {
+                        it.copy(
+                            isJoiningInvite = false,
+                            errorMessage = result.reason.toUiMessage(),
+                        )
+                    }
+                }
+            }
+        }
+    }
+
+    fun onNavigatedToPendingChat() {
+        _uiState.update { it.copy(pendingOpenChatId = null) }
+    }
+
     private fun observeChatStream() {
         viewModelScope.launch {
             selectedTab

android/app/src/test/java/ru/daemonlord/messenger/data/chat/repository/NetworkChatRepositoryTest.kt

@@ -14,6 +14,8 @@ import org.junit.Assert.assertEquals
 import org.junit.Assert.assertTrue
 import org.junit.Test
 import ru.daemonlord.messenger.data.chat.api.ChatApiService
+import ru.daemonlord.messenger.data.chat.dto.ChatInviteLinkDto
+import ru.daemonlord.messenger.data.chat.dto.ChatJoinByInviteRequestDto
 import ru.daemonlord.messenger.data.chat.dto.ChatReadDto
 import ru.daemonlord.messenger.data.chat.local.dao.ChatDao
 import ru.daemonlord.messenger.data.chat.local.entity.ChatEntity
@@ -109,6 +111,14 @@ class NetworkChatRepositoryTest {
         override suspend fun getChatById(chatId: Long): ChatReadDto {
             return chats.first()
         }
+
+        override suspend fun createInviteLink(chatId: Long): ChatInviteLinkDto {
+            return ChatInviteLinkDto(chatId = chatId, token = "token", inviteUrl = "https://chat.daemonlord.ru/invite/token")
+        }
+
+        override suspend fun joinByInvite(request: ChatJoinByInviteRequestDto): ChatReadDto {
+            return chats.first()
+        }
     }
 
     private class FakeChatDao(