Mirror: The highly customizable and versatile GraphQL client with which you add on features like normalized caching as you grow.
docs(graphcache): Add docs for flexible key generation (#3019)
authored by
Phil Pluckthun
and committed by
GitHub
e578fac3
7191074b
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docs/graphcache/normalized-caching.md
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docs/graphcache/normalized-caching.md
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});
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```
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### Flexible Key Generation
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In some cases, you may want to create a pattern for your key generation. For instance, you may want
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to say "create a special key for every type ending in `'Node'`. In such a case we recommend creating
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a small JS `Proxy` to take care of key generation for you and making the keys functional.
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```js
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cacheExchange({
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keys: new Proxy(
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{
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Image: () => null,
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},
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{
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get(target, prop, receiver) {
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if (prop.endsWith('Node')) {
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return data => data.uid;
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}
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const fallback = data => data.uuid;
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return target[prop] || fallback;
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},
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}
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),
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});
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```
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In the above example, we dynamically change the key generator depending on the typename. When
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a typename ends in `'Node'`, we return a key generator that uses the `uid` field. We still fall back
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to an object of manual key generation functions however. Lastly though, when a type doesn't have
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a predefined key generator, we change the default behavior from using `id` and `_id` fields to using
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`uuid` fields.
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## Non-Automatic Relations and Updates
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While _Graphcache_ is able to store and update our entities in an in-memory relational data