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Stream readable.unshift() Method

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Stream readable.unshift() Method

Isha only reaches for Stream readable.unshift() Method when read a big CSV has to stay correct in an upload job.

Do Stream readable.unshift() Method once by hand. createReadStream. Change one input. Say the new result out loud.

Skip Stream readable.unshift() Method and loading the whole file into RAM shows up in an upload job.

Stream readable.unshift() Method shows up in an upload job. Name read a big CSV, not “a real-world scenario”.

If read a big CSV breaks under Stream readable.unshift() Method, check loading the whole file into RAM first.

After Stream readable.unshift() Method, Isha should still remember loading the whole file into RAM.

Viva for Stream readable.unshift() Method: what it is → createReadStream → the mistake (loading the whole file into RAM).

Exam tip

Say Stream readable.unshift() Method in one breath, then createReadStream, then loading the whole file into RAM.

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 readable.unshift() Method — fs reads/writes files. Prefer promises/async APIs in real apps.

Short notes

DefStream readable.unshift() Method — Isha uses it for read a big CSV in an upload job.
RuleStream readable.unshift() Method → createReadStream.
RememberStream readable.unshift() Method + an Express route (an upload job).
UseStream readable.unshift() Method in an upload job (read a big CSV).
TrapStream readable.unshift() Method — loading the whole file into RAM.
ExStream readable.unshift() Method → 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 readable.unshift() Method

Example

Short notes

Questions

Stream readable.unshift() Method

Example

Short notes

Questions