Joor provides built-in support for Cross-Origin Resource Sharing (CORS), allowing you to securely share resources across different origins.

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Importing CORS

To use the CORS functionality in your Joor application, you need to import the cors function from the joor package:

import { cors } from 'joor';

The cors function takes an options object with these properties:

PropertyTypeDefaultDescription
originsstring[]["*"]An array of allowed URLs. Supports patterns like https://*.example.com.
methodsstring[]["*"]An array of uppercase HTTP methods (e.g., ["GET", "POST"]).
allowedHeadersstring[]["*"]An array of acceptable headers. Use capitalized headers, e.g., Content-Type.
exposedHeadersstring[] or stringundefinedA string or array listing headers exposed to clients. Optional.
allowsCookiesbooleanfalseA boolean indicating whether credentials are allowed.
maxAgenumber0A number (in seconds) that sets how long a preflight response is cached.

If any required array is missing or invalid, Joor defaults to ["*"]. Currently, only global CORS is supported.

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Pattern Matching in Origins

The origins property supports pattern matching to allow multiple subdomains or specific URL patterns. For example:

  • https://*.example.com allows any subdomain of example.com.

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Example Usage

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Basic Example

import Joor, { cors } from 'joor';
import { CORS_OPTIONS } from 'joor/types';

const app = new Joor();
const corsOptions: CORS_OPTIONS = {
  origins: ['http://localhost:3000'],
  methods: ['GET', 'POST'],
  allowedHeaders: ['Content-Type'],
  allowsCookies: true,
};

app.use(cors(corsOptions));
app.start();

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Example with All Defaults

import Joor, { cors } from 'joor';

const app = new Joor();

app.use(cors());
app.start();

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Example with Custom Headers and Methods

import Joor, { cors } from 'joor';
import { CORS_OPTIONS } from 'joor/types';

const app = new Joor();
const corsOptions: CORS_OPTIONS = {
  origins: ['https://*.example.com'],
  methods: ['GET', 'POST', 'PUT'],
  allowedHeaders: ['Content-Type', 'Authorization'],
  exposedHeaders: ['X-Custom-Header'],
  allowsCookies: false,
  maxAge: 3600,
};

app.use(cors(corsOptions));
app.start();

CORS_OPTIONS is a type alias covering all supported CORS properties. If the options provided are invalid or not an object, a cors-options-invalid exception is thrown. If the options object lacks valid required data, defaults are applied.