lesson-3.md

3. REST API

Goal

The goal of this lesson is to use your freshly gained knowledge about Prisma Client and use it to implement some routes of a REST API using Express.

Setup

You can continue working in the same prisma-workshop project that you set up in lesson 1. However, the starter for this lesson is located in the rest-api branch of the repo that you cloned.

Before you switch to that branch, you need to commit the current state of your project. For simplicity, you can use the stash command to do this:

git stash

After you ran this command, you can switch to the rest-api branch and delete the current migrations directory and dev.db file:

git checkout rest-api
rm -rf prisma/migrations
rm prisma/dev.db

Next, wipe your npm dependencies and re-install them to account for the new dependencies in package.json:

rm -rf node_modules
npm install

The data model you will use here is very similar to the one that you created before, only the Post model got extended with a few additional fields:

model User {
  id    Int     @id @default(autoincrement())
  email String  @unique
  name  String?
  posts Post[]
}

model Post {
  id        Int      @id @default(autoincrement())
  **createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt**
  title     String
  content   String?
  published Boolean  @default(false)
  **viewCount Int      @default(0)**
  author    User?    @relation(fields: [authorId], references: [id])
  authorId  Int?
}

Since you are starting over with your Prisma setup, you have to recreate the database and its tables. Run the following command to do this:

npx prisma migrate dev --name init

Finally, you can seed the database with some sample data that's specified in the prisma/seed.ts file. You can execute this seed script with this command:

npx prisma db seed --preview-feature

That's it, you're ready for your tasks now!

Tasks

You can find the tasks for this lesson inside the src/index.ts file marked with TODO. Your goal is to insert the right Prisma Client queries for each REST API route.

Note that this is in not a lesson in API design and you should think more carefully about designing your API operations in a real-world application.

If you're using VS Code, you can install the REST Client extension and test your implementation using the provided HTTP calls in test.http.

• View a quick demo of the VS Code REST Client extension

  !https://s3-us-west-2.amazonaws.com/secure.notion-static.com/529e9fc1-ec91-4c62-a06f-e1d29c517e7b/rest-client.gif

GET /users

Fetches all users.

• Solution

  app.get("/users", async (req, res) => {
    const result = await prisma.user.findMany()
    res.json(result)
  });

POST /signup

Creates a new user.

• Solution

  app.post(`/signup`, async (req, res) => {
    const { name, email } = req.body;
  
    const result = await prisma.user.create({
      data: {
        name,
        email
      }
    })
  
    res.json(result)
  });

POST /post

Creates a new post.

• Solution

  app.post(`/post`, async (req, res) => {
    const { title, content, authorEmail } = req.body;
  
    const result = await prisma.post.create({
      data: {
        title,
        content,
        author: {
          connect: {
            email: authorEmail
          }
        }
      }
    })
  
    res.json(result)
  });

PUT /post/:id/views

Increments the views of a post by 1.

• Solution

  app.put("/post/:id/views", async (req, res) => {
    const { id } = req.params;
  
    const result = await prisma.post.update({
      where: {
        id: Number(id),
      },
      data: {
        viewCount: {
          increment: 1,
        },
      },
    });
  
    res.json(result);
  });

PUT /publish/:id

Publishes a post.

• Solution

  app.put("/publish/:id", async (req, res) => {
    const { id } = req.params;
  
    const result = await prisma.post.update({
      where: { id: Number(id) },
      data: {
        published: true,
      },
    });
  
    res.json(result);
  });

GET /user/:id/drafts

Fetches the unpublished posts of a specific user.

• Solution

  app.get("/user/:id/drafts", async (req, res) => {
    const { id } = req.params;
  
    const result = await prisma.user.findUnique({
      where: { id: Number(id) },
    }).posts({
      where: {
        published: false
      }
    })
  
    res.json(result)
  });

GET /post/:id

Fetches a post by its ID.

• Solution

  app.get(`/post/:id`, async (req, res) => {
    const { id } = req.params;
  
    const result = await prisma.post.findUnique({
      where: { id: Number(id) },
    });
  
    res.json(result);
  });

GET /feed?searchString=<searchString>&skip=<skip>&take=<take>

Fetches all published posts and optionally paginates and/or filters them by checking whether the search string appears in either title or content.

• Solution

  app.get("/feed", async (req, res) => {
    const { searchString, skip, take } = req.query;
  
    const or = searchString ? {
      OR: [
        { title: { contains: searchString as string } },
        { content: { contains: searchString as string } },
      ],
    } : {}
  
    const result = await prisma.post.findMany({
      where: {
        published: true,
        ...or
      },
      skip: Number(skip) || undefined,
      take: Number(take) || undefined,
    });
  
    res.json(result);
  });