73 lines
1.8 KiB
Markdown
73 lines
1.8 KiB
Markdown
jsonStorage
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====
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A light abstraction for DOMStorage (such as localStorage).
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Installation
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===
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Ender.JS (Browser)
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ender build json-storage
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Node.JS (Server)
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npm install localStorage json-storage
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Usage
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===
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Made fo for Node.JS and Ender.JS (browser-side).
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var localStorage = require('localStorage')
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, JsonStorage = require('json-storage')
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, db = JsonStorage(localStorage, 'my-app-prefix')
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, myValue = {
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foo: "bar"
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, baz: "quux"
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}
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;
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db.set('myKey', myValue);
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myValue = db.get('myKey');
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API
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===
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* JsonStorage(DOMStorage, 'application-prefix') // optional prefix
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* get(key)
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* set(key, value)
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* remove(key)
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* clear()
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* keys()
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* size()
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null vs undefined in JSON
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===
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These notes do not reflect a bugs or defects in this library,
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they're simply to inform you of a few 'gotchas' inherent in JSON / DOMStorage conversion.
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99.999% of the time these gotchas shouldn't effect you in any way.
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If they do, you're probably doing something wrong in the first place.
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It is not valid to set `undefined` in JSON. So setting a key to `undefined` will remove it from the db.
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This means that `db.set('x')` is the same as `db.remove('x')`.
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To save `undefined`, use `null` instead.
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Note that both values that exist as `null` and values that don't exist at all will return `null`.
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db.set('existing-key', null);
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null === db.get('existing-key');
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null === db.get('non-existant-key');
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The special case of `null` as `"null"`, aka `"\"null\""`:
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`null`, and `"null"` both parse as `null` the "object", instead of one being the string (which would be `"\"null\""`).
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Objects containing `null`, however, parse as expected `{ "foo": null, "bar": "null" }` will parse as `foo` being `null` but `bar` being `"null"`, much unlike the value `"null"` being parsed on its own. |