52da0bbcac
It was something we forgot and that we don't want to forget. Sending it onto the event loop prevents us from blocking with a long operation, allowing other things on the event loop to happen before a take a possibly long time
27 lines
732 B
Markdown
27 lines
732 B
Markdown
### hashNode
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Creates a hash for a value using the [SHA-256](https://en.wikipedia.org/wiki/SHA-2) algorithm. Returns a promise.
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Use `crypto` API to create a hash for the given value, `setTimeout` to prevent blocking on a long operation, and a `Promise` to give it a familiar interface.
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```js
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const crypto = require('crypto');
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const hashNode = val =>
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new Promise(resolve =>
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setTimeout(
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() =>
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resolve(
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crypto
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.createHash('sha256')
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.update(val)
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.digest('hex')
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),
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0
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)
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);
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```
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```js
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hashNode(JSON.stringify({ a: 'a', b: [1, 2, 3, 4], foo: { c: 'bar' } })).then(console.log); // '04aa106279f5977f59f9067fa9712afc4aedc6f5862a8defc34552d8c7206393'
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```
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