Next.js: Projeto Final: CRUD & Server Actions

// Uma linha de Server Action completa a criação da tarefa + Atualização de Cache
<form action={createTask}>
  <input name="title" required />
  <input name="projectId" type="hidden" value={project.id} />
  <button type="submit">Criar Tarefa</button>
</form>

Diagrama: createTask; Validar com Zod; Criar com Prisma; revalidateTag; redirect; TaskForm.

// src/lib/actions/task-actions.ts
"use server"

import { revalidateTag } from "next/cache"
import { redirect } from "next/navigation"
import { z } from "zod"
import { prisma } from "@/lib/db"
import { auth } from "@/lib/auth"
import { TaskStatus, TaskPriority } from "@prisma/client"

const createTaskSchema = z.object({
  title: z.string().min(1, "Título é obrigatório").max(200, "Título muito longo"),
  description: z.string().max(2000).optional(),
  projectId: z.string().min(1),
  assigneeId: z.string().optional(),
  priority: z.nativeEnum(TaskPriority).optional(),
  dueDate: z.string().optional(),
})

const updateTaskSchema = z.object({
  id: z.string().min(1),
  title: z.string().min(1).max(200).optional(),
  description: z.string().max(2000).optional(),
  status: z.nativeEnum(TaskStatus).optional(),
  priority: z.nativeEnum(TaskPriority).optional(),
  assigneeId: z.string().nullable().optional(),
  dueDate: z.string().nullable().optional(),
  order: z.number().int().optional(),
})

export async function createTask(formData: FormData) {
  const session = await auth()
  if (!session?.user?.id) {
    throw new Error("Não autorizado")
  }

  const rawData = {
    title: formData.get("title") as string,
    description: formData.get("description") as string | undefined,
    projectId: formData.get("projectId") as string,
    assigneeId: formData.get("assigneeId") as string | undefined,
    priority: (formData.get("priority") as TaskPriority) || "MEDIUM",
    dueDate: formData.get("dueDate") as string | undefined,
  }

  const validated = createTaskSchema.safeParse(rawData)

  if (!validated.success) {
    return {
      error: validated.error.flatten().fieldErrors,
      message: "Falha na validação",
    }
  }

  const data = validated.data

  const maxOrder = await prisma.task.findFirst({
    where: { projectId: data.projectId, status: "TODO" },
    orderBy: { order: "desc" },
    select: { order: true },
  })

  await prisma.task.create({
    data: {
      title: data.title,
      description: data.description || null,
      status: "TODO",
      priority: data.priority || "MEDIUM",
      projectId: data.projectId,
      creatorId: session.user.id,
      assigneeId: data.assigneeId || null,
      dueDate: data.dueDate ? new Date(data.dueDate) : null,
      order: (maxOrder?.order ?? -1) + 1,
    },
  })

  revalidateTag("tasks")
  revalidateTag(`project-${data.projectId}`)
}

export async function updateTask(formData: FormData) {
  const session = await auth()
  if (!session?.user?.id) {
    throw new Error("Não autorizado")
  }

  const rawData = {
    id: formData.get("id") as string,
    title: formData.get("title") as string | undefined,
    description: formData.get("description") as string | undefined,
    status: formData.get("status") as TaskStatus | undefined,
    priority: formData.get("priority") as TaskPriority | undefined,
    assigneeId: formData.get("assigneeId") as string | null | undefined,
    dueDate: formData.get("dueDate") as string | null | undefined,
  }

  const validated = updateTaskSchema.safeParse(rawData)

  if (!validated.success) {
    return {
      error: validated.error.flatten().fieldErrors,
      message: "Falha na validação",
    }
  }

  const data = validated.data
  const updateData: Record<string, unknown> = {}

  if (data.title !== undefined) updateData.title = data.title
  if (data.description !== undefined) updateData.description = data.description
  if (data.status !== undefined) updateData.status = data.status
  if (data.priority !== undefined) updateData.priority = data.priority
  if (data.assigneeId !== undefined) updateData.assigneeId = data.assigneeId
  if (data.dueDate !== undefined) updateData.dueDate = data.dueDate ? new Date(data.dueDate) : null
  if (data.order !== undefined) updateData.order = data.order

  await prisma.task.update({
    where: { id: data.id },
    data: updateData,
  })

  revalidateTag("tasks")
}

export async function deleteTask(prevState: { message: string }, formData: FormData) {
  const session = await auth()
  if (!session?.user?.id) {
    return { message: "Não autorizado" }
  }

  const taskId = formData.get("id") as string

  if (!taskId) {
    return { message: "ID da tarefa é obrigatório" }
  }

  const task = await prisma.task.findUnique({
    where: { id: taskId },
    select: { creatorId: true, projectId: true },
  })

  if (!task) {
    return { message: "Tarefa não encontrada" }
  }

  if (task.creatorId !== session.user.id) {
    return { message: "Apenas o criador pode excluir esta tarefa" }
  }

  await prisma.task.delete({ where: { id: taskId } })

  revalidateTag("tasks")
  revalidateTag(`project-${task.projectId}`)

  return { message: "Tarefa excluída com sucesso" }
}

export async function reorderTask(taskId: string, newStatus: TaskStatus, newOrder: number) {
  const session = await auth()
  if (!session?.user?.id) {
    throw new Error("Não autorizado")
  }

  await prisma.task.update({
    where: { id: taskId },
    data: { status: newStatus, order: newOrder },
  })

  revalidateTag("tasks")
}

Aceita campos do formulário: title, description, projectId, assigneeId, priority.
Valida a entrada com o schema Zod antes do processamento.
Grava no banco de dados e invalida as tags de cache relevantes.

Diagrama ilustra a arquitetura/fluxo descrito.

// src/components/tasks/task-list.tsx
"use client"

import { useOptimistic } from "react"
import { TaskCard } from "@/components/tasks/task-card"
import type { TaskWithAssignee } from "@/types"

interface TaskListProps {
  tasks: TaskWithAssignee[]
  status: "TODO" | "IN_PROGRESS" | "DONE"
  onStatusChange: (taskId: string, newStatus: "TODO" | "IN_PROGRESS" | "DONE") => void
}

export function TaskList({ tasks, status, onStatusChange }: TaskListProps) {
  const [optimisticTasks, addOptimisticTask] = useOptimistic(
    tasks,
    (state, newTask: TaskWithAssignee) => {
      return [newTask, ...state]
    }
  )

  return (
    <div className="space-y-2">
      <h3 className="text-sm font-medium text-muted-foreground uppercase tracking-wide">
        {status.replace("_", " ")}
        <span className="ml-2 text-xs">({optimisticTasks.length})</span>
      </h3>
      {optimisticTasks.length === 0 ? (
        <div className="rounded-lg border border-dashed p-8 text-center text-sm text-muted-foreground">
          Nenhuma tarefa
        </div>
      ) : (
        <div className="space-y-2">
          {optimisticTasks.map((task) => (
            <TaskCard
              key={task.id}
              task={task}
              onStatusChange={onStatusChange}
            />
          ))}
        </div>
      )}
    </div>
  )
}

Renderiza a UI do componente ▶ Exemplo: useOptimistic — Atualizações Otimistas conforme descrito na seção.

O componente renderiza a UI descrita no navegador.

// src/components/tasks/delete-task-button.tsx
"use client"

import { useActionState, useState } from "react"
import { deleteTask } from "@/lib/actions/task-actions"
import { Button } from "@/components/ui/button"
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
  DialogTrigger,
} from "@/components/ui/dialog"

interface DeleteTaskButtonProps {
  taskId: string
  taskTitle: string
}

export function DeleteTaskButton({ taskId, taskTitle }: DeleteTaskButtonProps) {
  const [open, setOpen] = useState(false)
  const [state, formAction, isPending] = useActionState(deleteTask, {
    message: "",
  })

  return (
    <Dialog open={open} onOpenChange={setOpen}>
      <DialogTrigger asChild>
        <Button variant="ghost" size="icon" className="h-8 w-8 text-muted-foreground hover:text-destructive">
          <svg className="h-4 w-4" fill="none" viewBox="0 0 24 24" stroke="currentColor">
            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16" />
          </svg>
        </Button>
      </DialogTrigger>
      <DialogContent>
        <form action={formAction}>
          <input type="hidden" name="id" value={taskId} />
          <DialogHeader>
            <DialogTitle>Excluir Tarefa</DialogTitle>
            <DialogDescription>
              Tem certeza de que deseja excluir "{taskTitle}"? Esta ação não pode ser desfeita.
            </DialogDescription>
          </DialogHeader>
          {state.message && state.message !== "Tarefa excluída com sucesso" && (
            <div className="my-4 rounded-md bg-destructive/10 p-3 text-sm text-destructive">
              {state.message}
            </div>
          )}
          {state.message === "Tarefa excluída com sucesso" && (
            <div className="my-4 rounded-md bg-green-50 p-3 text-sm text-green-700">
              {state.message}
            </div>
          )}
          <DialogFooter className="mt-4">
            <Button
              type="button"
              variant="outline"
              onClick={() => setOpen(false)}
            >
              Cancelar
            </Button>
            <Button
              type="submit"
              variant="destructive"
              disabled={isPending}
            >
              {isPending ? "Excluindo..." : "Excluir"}
            </Button>
          </DialogFooter>
        </form>
      </DialogContent>
    </Dialog>
  )
}

Formulário interativo com gerenciamento de estado client-side.
Conteúdo visível: Excluir Tarefa

Diagrama da estrutura de layout e template no diretório app.

// src/components/tasks/task-board.tsx
"use client"

import { useCallback } from "react"
import { TaskList } from "@/components/tasks/task-list"
import { reorderTask } from "@/lib/actions/task-actions"
import type { TaskWithAssignee } from "@/types"

interface TaskBoardProps {
  tasks: TaskWithAssignee[]
}

export function TaskBoard({ tasks }: TaskBoardProps) {
  const todoTasks = tasks.filter((t) => t.status === "TODO")
  const inProgressTasks = tasks.filter((t) => t.status === "IN_PROGRESS")
  const doneTasks = tasks.filter((t) => t.status === "DONE")

  const handleStatusChange = useCallback(
    async (taskId: string, newStatus: "TODO" | "IN_PROGRESS" | "DONE") => {
      const targetList = tasks.filter((t) => t.status === newStatus)
      const maxOrder = targetList.length > 0
        ? Math.max(...targetList.map((t) => t.order))
        : 0

      try {
        await reorderTask(taskId, newStatus, maxOrder + 1)
      } catch (error) {
        console.error("Falha ao reordenar tarefa:", error)
      }
    },
    [tasks]
  )

  return (
    <div className="grid grid-cols-1 gap-6 md:grid-cols-3">
      <div className="rounded-lg bg-muted/50 p-4">
        <TaskList
          tasks={todoTasks}
          status="TODO"
          onStatusChange={handleStatusChange}
        />
      </div>
      <div className="rounded-lg bg-muted/50 p-4">
        <TaskList
          tasks={inProgressTasks}
          status="IN_PROGRESS"
          onStatusChange={handleStatusChange}
        />
      </div>
      <div className="rounded-lg bg-muted/50 p-4">
        <TaskList
          tasks={doneTasks}
          status="DONE"
          onStatusChange={handleStatusChange}
        />
      </div>
    </div>
  )
}

Renderiza a UI do componente ▶ Exemplo: Layout de três colunas para um quadro de tarefas conforme descrito na seção.

O componente renderiza a UI descrita no navegador.

// src/components/tasks/task-card.tsx
"use client"

import { DeleteTaskButton } from "@/components/tasks/delete-task-button"
import { Badge } from "@/components/ui/badge"
import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar"
import type { TaskWithAssignee } from "@/types"

interface TaskCardProps {
  task: TaskWithAssignee
  onStatusChange: (taskId: string, newStatus: "TODO" | "IN_PROGRESS" | "DONE") => void
}

const statusActions: Record<string, ("TODO" | "IN_PROGRESS" | "DONE")[]> = {
  TODO: ["IN_PROGRESS"],
  IN_PROGRESS: ["TODO", "DONE"],
  DONE: ["IN_PROGRESS"],
}

const priorityColors: Record<string, string> = {
  LOW: "bg-gray-100 text-gray-700",
  MEDIUM: "bg-blue-100 text-blue-700",
  HIGH: "bg-orange-100 text-orange-700",
  URGENT: "bg-red-100 text-red-700",
}

export function TaskCard({ task, onStatusChange }: TaskCardProps) {
  const initials = task.assignee?.name
    ?.split(" ")
    .map((n) => n[0])
    .join("")
    .toUpperCase()

  return (
    <div className="group rounded-lg border bg-card p-3 shadow-sm transition-all hover:shadow-md">
      <div className="flex items-start justify-between">
        <h4 className="text-sm font-medium">{task.title}</h4>
        <DeleteTaskButton taskId={task.id} taskTitle={task.title} />
      </div>

      {task.description && (
        <p className="mt-1 line-clamp-2 text-xs text-muted-foreground">
          {task.description}
        </p>
      )}

      <div className="mt-3 flex items-center justify-between">
        <div className="flex items-center gap-2">
          <Badge
            variant="secondary"
            className={priorityColors[task.priority]}
          >
            {task.priority}
          </Badge>
          {task.dueDate && (
            <span className="text-xs text-muted-foreground">
              {new Date(task.dueDate).toLocaleDateString("pt-BR", {
                month: "short",
                day: "numeric",
              })}
            </span>
          )}
        </div>

        <div className="flex items-center gap-2">
          <div className="flex gap-1 opacity-0 transition-opacity group-hover:opacity-100">
            {statusActions[task.status].map((action) => (
              <button
                key={action}
                onClick={() => onStatusChange(task.id, action)}
                className="rounded px-2 py-1 text-[10px] font-medium uppercase transition-colors hover:bg-accent"
              >
                {action === "TODO"
                  ? "\u21A9"
                  : action === "IN_PROGRESS"
                  ? "\u25B6"
                  : "\u2713"}
              </button>
            ))}
          </div>

          {task.assignee && (
            <Avatar className="h-6 w-6">
              <AvatarImage src={task.assignee.image ?? undefined} />
              <AvatarFallback className="text-[10px]">
                {initials}
              </AvatarFallback>
            </Avatar>
          )}
        </div>
      </div>

      {task._count?.comments > 0 && (
        <div className="mt-2 flex items-center gap-1 text-xs text-muted-foreground">
          <svg className="h-3 w-3" fill="none" viewBox="0 0 24 24" stroke="currentColor">
            <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={2} d="M8 12h.01M12 12h.01M16 12h.01M21 12c0 4.418-4.03 8-9 8a9.863 9.863 0 01-4.255-.949L3 20l1.395-3.72C3.512 15.042 3 13.574 3 12c0-4.418 4.03-8 9-8s9 3.582 9 8z" />
          </svg>
          {task._count.comments}
        </div>
      )}
    </div>
  )
}

Renderiza a UI do componente ▶ Exemplo: Componente Task Card conforme descrito na seção.

Diagrama de sequência mostrando o fluxo de mensagens entre os participantes.

// src/lib/uploadthing.ts
import { createUploadthing, type FileRouter } from "uploadthing/next"
import { auth } from "@/lib/auth"

const f = createUploadthing()

export const ourFileRouter = {
  taskAttachment: f({
    image: { maxFileSize: "4MB", maxFileCount: 5 },
    pdf: { maxFileSize: "8MB", maxFileCount: 3 },
    "text/*": { maxFileSize: "2MB", maxFileCount: 5 },
  })
    .middleware(async () => {
      const session = await auth()
      if (!session?.user) throw new Error("Não autorizado")
      return { userId: session.user.id }
    })
    .onUploadComplete(async ({ metadata, file }) => {
      return { uploadedBy: metadata.userId, fileUrl: file.url }
    }),
} satisfies FileRouter

export type OurFileRouter = typeof ourFileRouter

Define tipo(s) TypeScript: FileRouter, OurFileRouter.

// src/app/api/uploadthing/core.ts
import { createRouteHandler } from "uploadthing/next"
import { ourFileRouter } from "@/lib/uploadthing"

export const { GET, POST } = createRouteHandler({
  router: ourFileRouter,
})

// src/app/(dashboard)/dashboard/projects/[id]/page.tsx
import { Suspense } from "react"
import { prisma } from "@/lib/db"
import { auth } from "@/lib/auth"
import { notFound } from "next/navigation"
import { TaskBoard } from "@/components/tasks/task-board"
import { CreateTaskForm } from "@/components/tasks/create-task-form"
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card"
import { Badge } from "@/components/ui/badge"

interface ProjectBoardPageProps {
  params: Promise<{ id: string }>
}

export default async function ProjectBoardPage({ params }: ProjectBoardPageProps) {
  const { id } = await params
  const session = await auth()

  const project = await prisma.project.findUnique({
    where: { id },
    include: {
      _count: { select: { tasks: true } },
    },
  })

  if (!project) {
    notFound()
  }

  const tasks = await prisma.task.findMany({
    where: { projectId: id },
    orderBy: { order: "asc" },
    include: {
      assignee: { select: { name: true, image: true } },
      _count: { select: { comments: true, attachments: true } },
    },
  })

  const statusCounts = {
    TODO: tasks.filter((t) => t.status === "TODO").length,
    IN_PROGRESS: tasks.filter((t) => t.status === "IN_PROGRESS").length,
    DONE: tasks.filter((t) => t.status === "DONE").length,
  }

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <div>
          <div className="flex items-center gap-3">
            <div
              className="h-4 w-4 rounded-full"
              style={{ backgroundColor: project.color }}
            />
            <h1 className="text-2xl font-bold">{project.name}</h1>
            <Badge variant="secondary">
              {project.status}
            </Badge>
          </div>
          <p className="mt-1 text-sm text-muted-foreground">
            {tasks.length} tarefas · {statusCounts.TODO} a fazer ·{" "}
            {statusCounts.IN_PROGRESS} em andamento · {statusCounts.DONE} concluídas
          </p>
        </div>
      </div>

      <Suspense fallback={<div className="h-12 animate-pulse rounded-lg bg-muted" />}>
        <CreateTaskForm projectId={project.id} members={[]} />
      </Suspense>

      <TaskBoard tasks={tasks} />
    </div>
  )
}

→ Quadro Kanban de Três Colunas: A FAZER (8) | EM ANDAMENTO (5) | CONCLUÍDO (7)
→ Clique no botão "+" para abrir o Formulário de Criação Rápida → Digite um título → Enter → A tarefa aparece imediatamente na coluna A FAZER (Atualização Otimista)
→ Clique no botão ▶ do cartão da tarefa → Mover a tarefa para EM ANDAMENTO
→ Clique para Excluir → Exibir uma caixa de diálogo de confirmação → Confirmar Exclusão → A Tarefa Desapareceu
→ Arraste e solte arquivos na área de upload → Exibir uma barra de progresso → Anexos Associados às Tarefas
→ Pesquisar "auth" → Atualização do Parâmetro URL → DataTable Filtra para exibir tarefas correspondentes