Cliente

A biblioteca cliente conecta a um servidor PetraDB em execucao via HTTP.

Instalacao

JavaScript / TypeScript

npm install @petradb/client

Scala

libraryDependencies += "io.github.edadma" %%% "petradb-client" % "1.5.0"

Opcoes de Conexao

Opcao	Padrao	Descricao
host	"localhost"	Nome do host do servidor
port	5480	Porta do servidor
username	—	Nome de usuario para autenticacao Basic
password	—	Senha para autenticacao Basic

JavaScript / TypeScript

import { Session } from '@petradb/client';

const db = new Session({
  host: 'localhost',
  port: 5480,
  username: 'admin',
  password: 'secret',
});

Uso Stateless

Sem chamar connect(), cada chamada execute() executa em uma sessao transiente unica no servidor. Este e o modo mais simples — sem sessao para gerenciar.

const [{ rows }] = await db.execute('SELECT * FROM users');
console.log(rows);

Uso Stateful

Chame connect() para criar uma sessao no lado do servidor. O ID da sessao e enviado automaticamente com cada chamada execute() subsequente, para que transacoes e estado temporario persistam entre requisicoes.

await db.connect();

await db.execute('BEGIN');
await db.execute("INSERT INTO users (name) VALUES ('Alice')");
await db.execute('COMMIT');

const [{ rows }] = await db.execute('SELECT * FROM users');
console.log(rows);

await db.close();

Exemplo Completo

import { Session } from '@petradb/client';

const db = new Session({ host: 'localhost', port: 5480 });

await db.connect();

await db.execute(`
  CREATE TABLE products (
    id SERIAL,
    name TEXT NOT NULL,
    price NUMERIC(10,2),
    PRIMARY KEY (id)
  )
`);

await db.execute("INSERT INTO products (name, price) VALUES ('Laptop', 999.99)");
await db.execute("INSERT INTO products (name, price) VALUES ('Coffee', 4.50)");

const [{ rows }] = await db.execute('SELECT * FROM products ORDER BY price DESC');
console.log(rows);
// [{ id: 1, name: 'Laptop', price: 999.99 }, { id: 2, name: 'Coffee', price: 4.5 }]

await db.close();

Scala

import io.github.edadma.petradb.client.*
import scala.concurrent.ExecutionContext.Implicits.global

val session = new Session(SessionOptions(
  host = "localhost",
  port = 5480,
  username = Some("admin"),
  password = Some("secret"),
))

Uso Stateless

for results <- session.execute("SELECT * FROM users")
yield results.foreach(println)

Uso Stateful

for
  _       <- session.connect()
  _       <- session.execute("BEGIN")
  _       <- session.execute("INSERT INTO users (name) VALUES ('Alice')")
  _       <- session.execute("COMMIT")
  results <- session.execute("SELECT * FROM users")
  _       <- session.close()
yield results.foreach(println)

Todos os metodos retornam valores Future. connect() retorna o ID da sessao, execute() retorna Seq[Result] e close() retorna Unit.