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Blocking and Non-Blocking in Node.js

Theory

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Blocking and Non-Blocking in Node.js

Blocking and Non-Blocking (node js) is a Node.js idea you prove with wait for DB then reply, not with a slogan.

Keep Blocking and Non-Blocking (node js) small. Farhan should finish wait for DB then reply in a few lines, not a 40-line dump.

Without Blocking and Non-Blocking (node js), one Node process gets messy and wait for DB then reply is hard to trust.

Use Blocking and Non-Blocking (node js) when wait for DB then reply must stay clear. If a simpler Node.js step works, use that instead.

If wait for DB then reply breaks under Blocking and Non-Blocking (node js), check fs.readFileSync on a huge file first.

Place Blocking and Non-Blocking (node js) next to nearby Node.js work — async I/O, don’t block is the link.

Close Blocking and Non-Blocking (node js) with: “If I skip it, wait for DB then reply goes wrong like this: fs.readFileSync on a huge file.”

Exam tip

For Blocking and Non-Blocking (node js): definition + one Node process + one failure.

Example

// Blocking and Non-Blocking in Node.js
const users = [
  { id: 1, name: "Asha" },
  { id: 2, name: "Ravi" },
];

function findUser(id) {
  return users.find((u) => u.id === id) ?? null;
}

console.log(findUser(2));
console.log(users.map((u) => u.name));

Blocking and Non-Blocking in Node.js: find user 2, then list names. Say both prints.

Short notes

DefBlocking and Non-Blocking (node js) — Farhan uses it for wait for DB then reply in one Node process.
RuleBlocking and Non-Blocking (node js) → async I/O, don’t block.
RememberBlocking and Non-Blocking (node js) + an Express route (one Node process).
UseBlocking and Non-Blocking (node js) in one Node process (wait for DB then reply).
TrapBlocking and Non-Blocking (node js) — fs.readFileSync on a huge file.
ExBlocking and Non-Blocking (node js) → wait for DB then reply.

// Blocking and Non-Blocking in Node.js const users = [ { id: 1, name: "Asha" }, { id: 2, name: "Ravi" }, ]; function findUser(id) { return users.find((u) => u.id === id) ?? null; } console.log(findUser(2)); console.log(users.map((u) => u.name));

Blocking and Non-Blocking in Node.js

Example

Short notes

Questions

Blocking and Non-Blocking in Node.js

Example

Short notes

Questions