docs: correct node cache example

[hammerOwen]

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Changes

The cache implementation for node needs to return a Flags object not a JSON object.

How did you test this code?

No testing this is only documentation update

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Name	Status	Preview	Comments	Updated (UTC)
docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Feb 14, 2025 10:05am

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[rolodato]

Hi @hammerOwen, thanks for sending this over. You're right that this example is not correct, but I think neither is your suggested change:

There are several things wrong with the original example, which I'm surprised we didn't notice before. This looks like a correct example to me:

import { Flagsmith, Flags } from 'flagsmith-nodejs';
import type { BaseOfflineHandler, EnvironmentModel, FlagsmithCache } from 'flagsmith-nodejs';
import * as redis from 'redis';

const redisClient = redis.createClient({
    url: 'localhost:6379',
});

const redisFlagsmithCache = {
    async get(key: string): Promise<Flags | undefined> {
        const cachedValue = await redisClient.get(key);
        if (cachedValue) {
            return new Flags(JSON.parse(cachedValue));
        }
    },
    async set(key: string, value: Flags): Promise<void> {
        await redisClient.set(key, JSON.stringify(value), { EX: 60 });
    },
} satisfies FlagsmithCache;

Another change is that we're now using import instead of import type for Flags, since you can't instantiate classes imported with import type.

Let me know if that looks correct to you as well, and if it does add it to this PR and we'll get it merged.

[hammerOwen]

Updated the example with your corrections.