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diff --git a/follow-redirects/README.md b/follow-redirects/README.md new file mode 100644 index 0000000..ea618ab --- /dev/null +++ b/follow-redirects/README.md @@ -0,0 +1,148 @@ +## Follow Redirects + +Drop-in replacement for Node's `http` and `https` modules that automatically follows redirects. + +[](https://www.npmjs.com/package/follow-redirects) +[](https://github.com/follow-redirects/follow-redirects/actions) +[](https://coveralls.io/r/follow-redirects/follow-redirects?branch=master) +[](https://www.npmjs.com/package/follow-redirects) +[](https://github.com/sponsors/RubenVerborgh) + +`follow-redirects` provides [request](https://nodejs.org/api/http.html#http_http_request_options_callback) and [get](https://nodejs.org/api/http.html#http_http_get_options_callback) + methods that behave identically to those found on the native [http](https://nodejs.org/api/http.html#http_http_request_options_callback) and [https](https://nodejs.org/api/https.html#https_https_request_options_callback) + modules, with the exception that they will seamlessly follow redirects. + +```javascript +const { http, https } = require('follow-redirects'); + +http.get('http://bit.ly/900913', response => { + response.on('data', chunk => { + console.log(chunk); + }); +}).on('error', err => { + console.error(err); +}); +``` + +You can inspect the final redirected URL through the `responseUrl` property on the `response`. +If no redirection happened, `responseUrl` is the original request URL. + +```javascript +const request = https.request({ + host: 'bitly.com', + path: '/UHfDGO', +}, response => { + console.log(response.responseUrl); + // 'http://duckduckgo.com/robots.txt' +}); +request.end(); +``` + +## Options +### Global options +Global options are set directly on the `follow-redirects` module: + +```javascript +const followRedirects = require('follow-redirects'); +followRedirects.maxRedirects = 10; +followRedirects.maxBodyLength = 20 * 1024 * 1024; // 20 MB +``` + +The following global options are supported: + +- `maxRedirects` (default: `21`) – sets the maximum number of allowed redirects; if exceeded, an error will be emitted. + +- `maxBodyLength` (default: 10MB) – sets the maximum size of the request body; if exceeded, an error will be emitted. + +### Per-request options +Per-request options are set by passing an `options` object: + +```javascript +const url = require('url'); +const { http, https } = require('follow-redirects'); + +const options = url.parse('http://bit.ly/900913'); +options.maxRedirects = 10; +options.beforeRedirect = (options, { headers }) => { + // Use this to adjust the request options upon redirecting, + // to inspect the latest response headers, + // or to cancel the request by throwing an error + if (options.hostname === "example.com") { + options.auth = "user:password"; + } +}; +http.request(options); +``` + +In addition to the [standard HTTP](https://nodejs.org/api/http.html#http_http_request_options_callback) and [HTTPS options](https://nodejs.org/api/https.html#https_https_request_options_callback), +the following per-request options are supported: +- `followRedirects` (default: `true`) – whether redirects should be followed. + +- `maxRedirects` (default: `21`) – sets the maximum number of allowed redirects; if exceeded, an error will be emitted. + +- `maxBodyLength` (default: 10MB) – sets the maximum size of the request body; if exceeded, an error will be emitted. + +- `beforeRedirect` (default: `undefined`) – optionally change the request `options` on redirects, or abort the request by throwing an error. + +- `agents` (default: `undefined`) – sets the `agent` option per protocol, since HTTP and HTTPS use different agents. Example value: `{ http: new http.Agent(), https: new https.Agent() }` + +- `trackRedirects` (default: `false`) – whether to store the redirected response details into the `redirects` array on the response object. + + +### Advanced usage +By default, `follow-redirects` will use the Node.js default implementations +of [`http`](https://nodejs.org/api/http.html) +and [`https`](https://nodejs.org/api/https.html). +To enable features such as caching and/or intermediate request tracking, +you might instead want to wrap `follow-redirects` around custom protocol implementations: + +```javascript +const { http, https } = require('follow-redirects').wrap({ + http: require('your-custom-http'), + https: require('your-custom-https'), +}); +``` + +Such custom protocols only need an implementation of the `request` method. + +## Browser Usage + +Due to the way the browser works, +the `http` and `https` browser equivalents perform redirects by default. + +By requiring `follow-redirects` this way: +```javascript +const http = require('follow-redirects/http'); +const https = require('follow-redirects/https'); +``` +you can easily tell webpack and friends to replace +`follow-redirect` by the built-in versions: + +```json +{ + "follow-redirects/http" : "http", + "follow-redirects/https" : "https" +} +``` + +## Contributing + +Pull Requests are always welcome. Please [file an issue](https://github.com/follow-redirects/follow-redirects/issues) + detailing your proposal before you invest your valuable time. Additional features and bug fixes should be accompanied + by tests. You can run the test suite locally with a simple `npm test` command. + +## Debug Logging + +`follow-redirects` uses the excellent [debug](https://www.npmjs.com/package/debug) for logging. To turn on logging + set the environment variable `DEBUG=follow-redirects` for debug output from just this module. When running the test + suite it is sometimes advantageous to set `DEBUG=*` to see output from the express server as well. + +## Authors + +- [Ruben Verborgh](https://ruben.verborgh.org/) +- [Olivier Lalonde](mailto:olalonde@gmail.com) +- [James Talmage](mailto:james@talmage.io) + +## License + +[MIT License](https://github.com/follow-redirects/follow-redirects/blob/master/LICENSE) |