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diff --git a/backend/node_modules/on-finished/README.md b/backend/node_modules/on-finished/README.md new file mode 100644 index 0000000..8973cde --- /dev/null +++ b/backend/node_modules/on-finished/README.md @@ -0,0 +1,162 @@ +# on-finished + +[![NPM Version][npm-version-image]][npm-url] +[![NPM Downloads][npm-downloads-image]][npm-url] +[![Node.js Version][node-image]][node-url] +[![Build Status][ci-image]][ci-url] +[![Coverage Status][coveralls-image]][coveralls-url] + +Execute a callback when a HTTP request closes, finishes, or errors. + +## Install + +This is a [Node.js](https://nodejs.org/en/) module available through the +[npm registry](https://www.npmjs.com/). Installation is done using the +[`npm install` command](https://docs.npmjs.com/getting-started/installing-npm-packages-locally): + +```sh +$ npm install on-finished +``` + +## API + +```js +var onFinished = require('on-finished') +``` + +### onFinished(res, listener) + +Attach a listener to listen for the response to finish. The listener will +be invoked only once when the response finished. If the response finished +to an error, the first argument will contain the error. If the response +has already finished, the listener will be invoked. + +Listening to the end of a response would be used to close things associated +with the response, like open files. + +Listener is invoked as `listener(err, res)`. + +<!-- eslint-disable handle-callback-err --> + +```js +onFinished(res, function (err, res) { + // clean up open fds, etc. + // err contains the error if request error'd +}) +``` + +### onFinished(req, listener) + +Attach a listener to listen for the request to finish. The listener will +be invoked only once when the request finished. If the request finished +to an error, the first argument will contain the error. If the request +has already finished, the listener will be invoked. + +Listening to the end of a request would be used to know when to continue +after reading the data. + +Listener is invoked as `listener(err, req)`. + +<!-- eslint-disable handle-callback-err --> + +```js +var data = '' + +req.setEncoding('utf8') +req.on('data', function (str) { + data += str +}) + +onFinished(req, function (err, req) { + // data is read unless there is err +}) +``` + +### onFinished.isFinished(res) + +Determine if `res` is already finished. This would be useful to check and +not even start certain operations if the response has already finished. + +### onFinished.isFinished(req) + +Determine if `req` is already finished. This would be useful to check and +not even start certain operations if the request has already finished. + +## Special Node.js requests + +### HTTP CONNECT method + +The meaning of the `CONNECT` method from RFC 7231, section 4.3.6: + +> The CONNECT method requests that the recipient establish a tunnel to +> the destination origin server identified by the request-target and, +> if successful, thereafter restrict its behavior to blind forwarding +> of packets, in both directions, until the tunnel is closed. Tunnels +> are commonly used to create an end-to-end virtual connection, through +> one or more proxies, which can then be secured using TLS (Transport +> Layer Security, [RFC5246]). + +In Node.js, these request objects come from the `'connect'` event on +the HTTP server. + +When this module is used on a HTTP `CONNECT` request, the request is +considered "finished" immediately, **due to limitations in the Node.js +interface**. This means if the `CONNECT` request contains a request entity, +the request will be considered "finished" even before it has been read. + +There is no such thing as a response object to a `CONNECT` request in +Node.js, so there is no support for one. + +### HTTP Upgrade request + +The meaning of the `Upgrade` header from RFC 7230, section 6.1: + +> The "Upgrade" header field is intended to provide a simple mechanism +> for transitioning from HTTP/1.1 to some other protocol on the same +> connection. + +In Node.js, these request objects come from the `'upgrade'` event on +the HTTP server. + +When this module is used on a HTTP request with an `Upgrade` header, the +request is considered "finished" immediately, **due to limitations in the +Node.js interface**. This means if the `Upgrade` request contains a request +entity, the request will be considered "finished" even before it has been +read. + +There is no such thing as a response object to a `Upgrade` request in +Node.js, so there is no support for one. + +## Example + +The following code ensures that file descriptors are always closed +once the response finishes. + +```js +var destroy = require('destroy') +var fs = require('fs') +var http = require('http') +var onFinished = require('on-finished') + +http.createServer(function onRequest (req, res) { + var stream = fs.createReadStream('package.json') + stream.pipe(res) + onFinished(res, function () { + destroy(stream) + }) +}) +``` + +## License + +[MIT](LICENSE) + +[ci-image]: https://badgen.net/github/checks/jshttp/on-finished/master?label=ci +[ci-url]: https://github.com/jshttp/on-finished/actions/workflows/ci.yml +[coveralls-image]: https://badgen.net/coveralls/c/github/jshttp/on-finished/master +[coveralls-url]: https://coveralls.io/r/jshttp/on-finished?branch=master +[node-image]: https://badgen.net/npm/node/on-finished +[node-url]: https://nodejs.org/en/download +[npm-downloads-image]: https://badgen.net/npm/dm/on-finished +[npm-url]: https://npmjs.org/package/on-finished +[npm-version-image]: https://badgen.net/npm/v/on-finished |