Postman

TL;DR

Qué: Plataforma de desarrollo de API para construir, probar y documentar APIs.

Por qué: Interfaz visual, colecciones, entornos, pruebas automatizadas, colaboración en equipo.

Quick Start

Instalar: Descargar desde postman.com/downloads

Primera solicitud:

1. Haz clic en New → Request
2. Ingresa la URL: https://jsonplaceholder.typicode.com/posts/1
3. Haz clic en Send
4. Ver la respuesta en el panel inferior

Crear colección:

1. Haz clic en Collections → Create Collection
2. Nómbrala “My API”
3. Añade solicitudes para organizar

Cheatsheet

Característica	Descripción
Collections	Organizar solicitudes
Environments	Conjuntos de variables (dev/prod)
Variables	Sintaxis {{variable}}
Pre-request Script	Ejecutar antes de la solicitud
Tests	Validar respuestas
Runner	Ejecución por lotes

Gotchas

Variables de entorno

// Set in environment
// BASE_URL: https://api.example.com
// TOKEN: your-auth-token

// Use in request URL
// {{BASE_URL}}/users

// Use in headers
// Authorization: Bearer {{TOKEN}}

Script de pre-solicitud

// Generate timestamp
pm.environment.set("timestamp", Date.now());

// Generate random data
pm.environment.set("randomEmail", `user${Math.random().toString(36).slice(2)}@test.com`);

// Get data from previous request
const token = pm.environment.get("authToken");
pm.request.headers.add({
    key: "Authorization",
    value: `Bearer ${token}`
});

Scripts de prueba

// Check status
pm.test("Status code is 200", function () {
    pm.response.to.have.status(200);
});

// Check response time
pm.test("Response time < 500ms", function () {
    pm.expect(pm.response.responseTime).to.be.below(500);
});

// Check response body
pm.test("Has user id", function () {
    const json = pm.response.json();
    pm.expect(json).to.have.property("id");
    pm.expect(json.id).to.be.a("number");
});

// Save to environment
const json = pm.response.json();
pm.environment.set("userId", json.id);

// Check array
pm.test("Returns array of users", function () {
    const json = pm.response.json();
    pm.expect(json).to.be.an("array");
    pm.expect(json.length).to.be.greaterThan(0);
});

Collection Runner

// Run collection with data file (CSV/JSON)
// data.json:
[
    { "email": "[email protected]", "name": "User 1" },
    { "email": "[email protected]", "name": "User 2" }
]

// In request body
{
    "email": "{{email}}",
    "name": "{{name}}"
}

// Access iteration data in tests
pm.test("User created", function () {
    const json = pm.response.json();
    pm.expect(json.email).to.eql(pm.iterationData.get("email"));
});

Newman CLI

# Install
npm install -g newman

# Run collection
newman run collection.json

# With environment
newman run collection.json -e environment.json

# Generate report
newman run collection.json -r html

Next Steps

• Postman Learning Center - Tutoriales
• Postman API - API Postman
• Newman - CLI Runner
• Postman Flows - Flujos visuales