René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Byte stream support for Socket readableWebStream","articleBody":"### What is the problem this feature will solve?\r\n\r\nAs mentioned by the [winterCG](https://sockets-api.proposal.wintercg.org/#readable-attribute/) it is reasonable to assume that most TCP cases are bytes oriented. And my case (MQTT server/client) is one of them.\r\n\r\nHowever: \r\n```javascript\r\nimport { createConnection } from \"node:net\";\r\nimport { Readable } from \"node:stream\";\r\n\r\nconst socket = createConnection({ port:1883, host: \"localhost\" }, () =\u003e {\r\n    const readable= Readable.toWeb(socket);\r\n    const reader = readable.getReader({ mode: \"byob\" });\r\n});\r\n``` \r\n\r\nGives me:\r\n```\r\n node:internal/webstreams/readablestream:2280\r\n    throw new ERR_INVALID_ARG_VALUE('stream', stream, 'must be a byte stream');\r\n    ^\r\n\r\nTypeError [ERR_INVALID_ARG_VALUE]: The argument 'stream' must be a byte stream. Received ReadableStream { locked: false, state: 'readable', supportsBYOB: false }\r\n    at setupReadableStreamBYOBReader (node:internal/webstreams/readablestream:2280:11)\r\n    at new ReadableStreamBYOBReader (node:internal/webstreams/readablestream:935:5)\r\n    at ReadableStream.getReader (node:internal/webstreams/readablestream:346:12)\r\n    at Socket.\u003canonymous\u003e (file:///home/hansklunder/github/opifex/tmp.js:6:29)\r\n    at Object.onceWrapper (node:events:632:28)\r\n    at Socket.emit (node:events:518:28)\r\n    at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1595:10) {\r\n  code: 'ERR_INVALID_ARG_VALUE'\r\n}\r\n```\r\n\r\nWhich makes sense in its current implementation.\r\n\r\nSolving this would bring better compatibility with the WinterCG standards and would make it easier to implement TCP bytestream protocols in NodeJS.\r\n\r\n \r\n\r\n### What is the feature you are proposing to solve the problem?\r\n\r\nIt would be nice if I could signal either at the creation of the socket or the Readable.toWeb() that I want a ReadableByteStream instead of ReadableDefaultStream.\r\n\r\nEven more brilliant would be if I could skip the `Readable.toWeb()` call also somehow, e.g. by importing `node:sockets` or something similar.\r\n\r\n### What alternatives have you considered?\r\n\r\nI've currently hacked my own layer on top of the socket event API:\r\n\r\n``` javascript\r\nimport { Writable } from \"node:stream\";\r\nfunction closer(sock) {\r\n    if (!sock.closed) {\r\n        sock.end();\r\n    }\r\n}\r\nexport function wrapNodeSocket(socket) {\r\n    const readable = new ReadableStream({\r\n        type: \"bytes\",\r\n        start(controller) {\r\n            socket.on(\"data\", (data) =\u003e {\r\n                controller.enqueue(data);\r\n                const desiredSize = controller.desiredSize ?? 0;\r\n                if (desiredSize \u003c= 0) {\r\n                    // The internal queue is full, so propagate\r\n                    // the backpressure signal to the underlying source.\r\n                    socket.pause();\r\n                }\r\n            });\r\n            socket.on(\"error\", (err) =\u003e controller.error(err));\r\n            socket.on(\"end\", () =\u003e {\r\n                // close the controller\r\n                controller.close();\r\n                // and unlock the last BYOB read request\r\n                controller.byobRequest?.respond(0);\r\n            });\r\n        },\r\n        pull: () =\u003e {\r\n            socket.resume();\r\n        },\r\n        cancel: () =\u003e {\r\n            socket.end();\r\n        },\r\n    });\r\n    const writable = Writable.toWeb(socket);\r\n    const remoteAddr = {\r\n        hostname: socket.remoteAddress || \"\",\r\n        port: socket.remotePort || 0,\r\n    };\r\n    const conn = {\r\n        readable: readable,\r\n        writable: writable,\r\n        close: () =\u003e closer(socket),\r\n        remoteAddr,\r\n    };\r\n    return conn;\r\n}\r\n```\r\nThis works, but it would be nice if it was part of standard NodeJS functionality.\r\n","author":{"url":"https://github.com/seriousme","@type":"Person","name":"seriousme"},"datePublished":"2024-11-26T18:09:57.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/56004/node/issues/56004"}