Node.js · Theory

Stream writable.writableLength Property

Theory

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Stream writable.writableLength Property

Don’t start Stream writable.writableLength Property with jargon. Start with read a big CSV. That is the whole point.

Do Stream writable.writableLength Property once by hand. createReadStream. Change one input. Say the new result out loud.

Stream writable.writableLength Property exists so Kabir can keep read a big CSV correct in an upload job.

Stream writable.writableLength Property shows up in an upload job. Name read a big CSV, not “a real-world scenario”.

Stream writable.writableLength Property trap: loading the whole file into RAM. Kabir loses marks for that every viva.

After Stream writable.writableLength Property, Kabir should still remember loading the whole file into RAM.

Viva for Stream writable.writableLength Property: what it is → createReadStream → the mistake (loading the whole file into RAM).

Exam tip

For Stream writable.writableLength Property: definition + an upload job + one failure.

Example

const fs = require("fs");
const path = require("path");

const file = path.join(__dirname || ".", "demo.txt");
fs.writeFileSync(file, "hello node\n");
const text = fs.readFileSync(file, "utf8");
console.log(text.trim());
fs.unlinkSync(file);

Stream writable.writableLength Property — fs reads/writes files. Prefer promises/async APIs in real apps.

Short notes

DefStream writable.writableLength Property — Kabir uses it for read a big CSV in an upload job.
RuleStream writable.writableLength Property → createReadStream.
RememberStream writable.writableLength Property + npm (an upload job).
UseStream writable.writableLength Property in an upload job (read a big CSV).
TrapStream writable.writableLength Property — loading the whole file into RAM.
ExStream writable.writableLength Property → read a big CSV.

const fs = require("fs"); const path = require("path"); const file = path.join(__dirname || ".", "demo.txt"); fs.writeFileSync(file, "hello node\n"); const text = fs.readFileSync(file, "utf8"); console.log(text.trim()); fs.unlinkSync(file);

Stream writable.writableLength Property

Example

Short notes

Questions

Stream writable.writableLength Property

Example

Short notes

Questions