Lazy Loading

[MinnDevelopment]

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Changes

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Closes Issue: NaN

Description

Implementation for lazy loading of guild members. This will disable the member chunking performed when the guild is received and instead load members as they appear. This obviously removes a lot of information but can be very useful for large bots that see a lot of members which are never active.

The only information missing when creating a member from a presence update seems to be the join date, we could in theory just disable this caching during lazy loading. Currently I just set the join date to the guild creation time instead.

You can dynamically load the entire member cache for a guild or single members.

guild.retrieveMembers().thenRun(() -> {
    // use guild with members loaded
});

guild.retrieveMemberById(86699011792191488L).queue((member) -> {
    // use member loaded through either cache or http request
});

This also adds support for disabling guild_subscriptions which disables all guild subscriptions such as presence and typing events. When guild subscriptions are disabled the user cache becomes inconsistent as discord will not inform us of updates directly. However, we can update the cached users through message and voice state events and REST calls.
We disable the user cache completely in this case because there are no member update events so there is no way to make a working system of caching them. The only users that get cached are users who participate in voice channels.

Example

new JDABuilder(TOKEN)
    .setGuildSubscriptionsEnabled(false)
    .setChunkingFilter(ChunkingFilter.include(125227483518861312L, 81384788765712384L));