Model user

infra/controller.js

@@ -1,11 +1,20 @@
-import { InternalServerError, MethodNotAllowedError } from "infra/errors";
+import {
+  InternalServerError,
+  MethodNotAllowedError,
+  ValidationError,
+  NotFoundError,
+} from "infra/errors";
 
 function onNoMatchHandler(request, response) {
   const publicErrorObject = new MethodNotAllowedError();
   response.status(publicErrorObject.statusCode).json(publicErrorObject);
 }
 
 function onErrorHandler(error, request, response) {
+  if (error instanceof ValidationError || error instanceof NotFoundError) {
+    return response.status(error.statusCode).json(error);
+  }
+
   const publicErrorObject = new InternalServerError({
     statusCode: error.statusCode,
     cause: error,

infra/errors.js

@@ -38,6 +38,47 @@ export class ServiceError extends Error {
   }
 }
 
+export class ValidationError extends Error {
+  constructor({ cause, message, action }) {
+    super(message || "Um erro de validação ocorreu.", {
+      cause,
+    });
+    this.name = "ValidationError";
+    this.action = action || "Ajuste os dados enviados e tente novamente.";
+    this.statusCode = 400;
+  }
+
+  toJSON() {
+    return {
+      name: this.name,
+      message: this.message,
+      action: this.action,
+      status_code: this.statusCode,
+    };
+  }
+}
+
+export class NotFoundError extends Error {
+  constructor({ cause, message, action }) {
+    super(message || "Não foi possível encontrar este recurso no sistema.", {
+      cause,
+    });
+    this.name = "NotFoundError";
+    this.action =
+      action || "Verifique se os parâmetros enviados na consulta estão certos.";
+    this.statusCode = 404;
+  }
+
+  toJSON() {
+    return {
+      name: this.name,
+      message: this.message,
+      action: this.action,
+      status_code: this.statusCode,
+    };
+  }
+}
+
 export class MethodNotAllowedError extends Error {
   constructor() {
     super("Método não permitido para este endpoint.");

infra/migrations/1755978902703_users.js

@@ -0,0 +1,44 @@
+exports.up = (pgm) => {
+  pgm.createTable("users", {
+    id: {
+      type: "uuid",
+      primaryKey: true,
+      default: pgm.func("gen_random_uuid()"),
+    },
+
+    // For reference, GitHub limits usernames to 39 characters.
+    username: {
+      type: "varchar(30)",
+      notNull: true,
+      unique: true,
+    },
+
+    // Why 254 in length? https://stackoverflow.com/a/1199238
+    email: {
+      type: "varchar(254)",
+      notNull: true,
+      unique: true,
+    },
+
+    // Why 60 in length? https://www.npmjs.com/package/bcrypt#hash-info
+    password: {
+      type: "varchar(60)",
+      notNull: true,
+    },
+
+    // Why timestamp with timezone? https://justatheory.com/2012/04/postgres-use-timestamptz/
+    created_at: {
+      type: "timestamptz",
+      notNull: true,
+      default: pgm.func("timezone('utc', now())"),
+    },
+
+    updated_at: {
+      type: "timestamptz",
+      notNull: true,
+      default: pgm.func("timezone('utc', now())"),
+    },
+  });
+};
+
+exports.down = false;

models/migrator.js

@@ -6,7 +6,7 @@ const defaultMigrationOptions = {
   dryRun: true,
   dir: resolve("infra", "migrations"),
   direction: "up",
-  verbose: true,
+  log: () => {},
   migrationsTable: "pgmigrations",
 };
 

models/user.js

@@ -0,0 +1,109 @@
+import database from "infra/database.js";
+import { ValidationError, NotFoundError } from "infra/errors.js";
+
+async function findOneByUsername(username) {
+  const userFound = await runSelectQuery(username);
+
+  return userFound;
+
+  async function runSelectQuery(username) {
+    const results = await database.query({
+      text: `
+        SELECT
+          *
+        FROM
+          users
+        WHERE
+          LOWER(username) = LOWER($1)
+        LIMIT
+          1
+        ;`,
+      values: [username],
+    });
+
+    if (results.rowCount === 0) {
+      throw new NotFoundError({
+        message: "O username informado não foi encontrado no sistema.",
+        action: "Verifique se o username está digitado corretamente.",
+      });
+    }
+
+    return results.rows[0];
+  }
+}
+
+async function create(userInputValues) {
+  await validateUniqueEmail(userInputValues.email);
+  await validateUniqueUsername(userInputValues.username);
+
+  const newUser = await runInsertQuery(userInputValues);
+  return newUser;
+
+  async function validateUniqueEmail(email) {
+    const results = await database.query({
+      text: `
+        SELECT
+          email
+        FROM
+          users
+        WHERE
+          LOWER(email) = LOWER($1)
+        ;`,
+      values: [email],
+    });
+
+    if (results.rowCount > 0) {
+      throw new ValidationError({
+        message: "O email informado já está sendo utilizado.",
+        action: "Utilize outro email para realizar o cadastro.",
+      });
+    }
+  }
+
+  async function validateUniqueUsername(username) {
+    const results = await database.query({
+      text: `
+        SELECT
+          username
+        FROM
+          users
+        WHERE
+          LOWER(username) = LOWER($1)
+        ;`,
+      values: [username],
+    });
+
+    if (results.rowCount > 0) {
+      throw new ValidationError({
+        message: "O username informado já está sendo utilizado.",
+        action: "Utilize outro username para realizar o cadastro.",
+      });
+    }
+  }
+
+  async function runInsertQuery(userInputValues) {
+    const results = await database.query({
+      text: `
+        INSERT INTO
+          users (username, email, password)
+        VALUES
+          ($1, $2, $3)
+        RETURNING
+          *
+        ;`,
+      values: [
+        userInputValues.username,
+        userInputValues.email,
+        userInputValues.password,
+      ],
+    });
+    return results.rows[0];
+  }
+}
+
+const user = {
+  create,
+  findOneByUsername,
+};
+
+export default user;

package.json

@@ -32,7 +32,8 @@
     "pg": "8.11.3",
     "react": "18.2.0",
     "react-dom": "18.2.0",
-    "swr": "2.2.5"
+    "swr": "2.2.5",
+    "uuid": "11.1.0"
   },
   "devDependencies": {
     "@commitlint/cli": "19.3.0",

pages/api/v1/users/[username]/index.js

@@ -0,0 +1,15 @@
+import { createRouter } from "next-connect";
+import controller from "infra/controller.js";
+import user from "models/user.js";
+
+const router = createRouter();
+
+router.get(getHandler);
+
+export default router.handler(controller.errorHandlers);
+
+async function getHandler(request, response) {
+  const username = request.query.username;
+  const userFound = await user.findOneByUsername(username);
+  return response.status(200).json(userFound);
+}

pages/api/v1/users/index.js

@@ -0,0 +1,15 @@
+import { createRouter } from "next-connect";
+import controller from "infra/controller.js";
+import user from "models/user.js";
+
+const router = createRouter();
+
+router.post(postHandler);
+
+export default router.handler(controller.errorHandlers);
+
+async function postHandler(request, response) {
+  const userInputValues = request.body;
+  const newUser = await user.create(userInputValues);
+  return response.status(201).json(newUser);
+}