pub trait Backend {
    type Error: Error;

Show 46 methods fn set_current_user<'life0, 'async_trait>(
        &'life0 self,
        current_user: CurrentUser
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_channel<'life0, 'async_trait>(
        &'life0 self,
        channel: CachedChannel
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_channel<'life0, 'async_trait>(
        &'life0 self,
        channel_id: Id<ChannelMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_permission_overwrite<'life0, 'async_trait>(
        &'life0 self,
        permission_overwrite: CachedPermissionOverwrite
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_channel_permission_overwrites<'life0, 'async_trait>(
        &'life0 self,
        channel_id: Id<ChannelMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_channels<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_private_channel<'life0, 'async_trait>(
        &'life0 self,
        channel_id: Id<ChannelMarker>,
        user_id: Id<UserMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_guild<'life0, 'async_trait>(
        &'life0 self,
        guild: CachedGuild
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_emoji<'life0, 'async_trait>(
        &'life0 self,
        emoji: CachedEmoji
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_emoji<'life0, 'async_trait>(
        &'life0 self,
        emoji_id: Id<EmojiMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_emojis<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_sticker<'life0, 'async_trait>(
        &'life0 self,
        sticker: CachedSticker
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_sticker<'life0, 'async_trait>(
        &'life0 self,
        sticker_id: Id<StickerMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_stickers<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_member<'life0, 'async_trait>(
        &'life0 self,
        member: CachedMember
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_member<'life0, 'async_trait>(
        &'life0 self,
        user_id: Id<UserMarker>,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_members<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_message<'life0, 'async_trait>(
        &'life0 self,
        message: CachedMessage
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_message<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_embed<'life0, 'async_trait>(
        &'life0 self,
        embed: CachedEmbed
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_embed<'life0, 'async_trait>(
        &'life0 self,
        embed_id: Id<GenericMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_embed_field<'life0, 'async_trait>(
        &'life0 self,
        embed_field: CachedEmbedField
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_embed_fields<'life0, 'async_trait>(
        &'life0 self,
        embed_id: Id<GenericMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn cached_embeds<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<Vec<CachedEmbed>, Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn embed_fields<'life0, 'async_trait>(
        &'life0 self,
        embed_id: Id<GenericMarker>
    ) -> Pin<Box<dyn Future<Output = Result<Vec<CachedEmbedField>, Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_attachment<'life0, 'async_trait>(
        &'life0 self,
        attachment: CachedAttachment
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_message_attachments<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_message_sticker<'life0, 'async_trait>(
        &'life0 self,
        sticker: CachedMessageSticker
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_message_stickers<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_presence<'life0, 'async_trait>(
        &'life0 self,
        presence: CachedPresence
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_presence<'life0, 'async_trait>(
        &'life0 self,
        user_id: Id<UserMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_presences<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_activity<'life0, 'async_trait>(
        &'life0 self,
        activity: CachedActivity
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_user_activities<'life0, 'async_trait>(
        &'life0 self,
        user_id: Id<UserMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_reaction<'life0, 'async_trait>(
        &'life0 self,
        reaction: CachedReaction
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_reaction<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>,
        user_id: Id<UserMarker>,
        emoji: String
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_message_reactions_by_emoji<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>,
        emoji: String
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_message_reactions<'life0, 'async_trait>(
        &'life0 self,
        message_id: Id<MessageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_role<'life0, 'async_trait>(
        &'life0 self,
        role: CachedRole
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_role<'life0, 'async_trait>(
        &'life0 self,
        role_id: Id<RoleMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_roles<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_member_roles<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>,
        user_id: Id<UserMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn upsert_stage_instance<'life0, 'async_trait>(
        &'life0 self,
        stage: StageInstance
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_stage_instance<'life0, 'async_trait>(
        &'life0 self,
        stage_id: Id<StageMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
; fn delete_guild_stage_instances<'life0, 'async_trait>(
        &'life0 self,
        guild_id: Id<GuildMarker>
    ) -> Pin<Box<dyn Future<Output = Result<(), Self::Error>> + Send + 'async_trait>>
    where
        'life0: 'async_trait,
        Self: 'async_trait
;
}
Expand description

Provides methods to add or replace data in the cache

This is for adding support for a backend, users of the cache itself only need the methods in super::Cache

All of the IDs are unique unless documented otherwise, this means if the ID is already in the cache, the new value’s fields should overwrite the current fields, most backends abstract over this

This trait is not complete

You should expose the backend so that users can filter the results in the query, for example they can do SELECT * FROM users WHERE name = ?

It’s also advisable to implement your backend library’s traits to (de)serialize Discord models for the backend to streamline your codebase

Creating indexes for every ID field/column (for example, both user_id and guild_id in users) will be a huge performance improvement

Example

Though the example uses PostgresSQL, you can use this library with any SQL or NoSQL backend

use sparkle_cache::backend::Backend;
use twilight_model::id::{
    marker::{GuildMarker, UserMarker},
    Id,
};

struct MyCache {
    pub db: sql_library::Database, // Or add a getter method instead of making the field public
};

impl MyCache {
    fn new() {
        let db = sql_library::Database::connect("postgresql://localhost/discord");
        db.query("CREATE UNIQUE INDEX channels_idx ON channels (channel_id);");
        db.query("CREATE INDEX channels_guild_id_idx ON channels (guild_id);");
    }
}

impl Backend for MyCache {
    type Error = sqlx::Error;

    async fn upsert_channel(&self, channel: CachedChannel) -> Result<(), Self::Error> {
        sqlx::query!(
            channel.id,
            // Other fields here
            "INSERT INTO channels (id, ...) VALUES ($1, ...)"
        ).exec(&self.db)?;
        Ok(())
    }
    // Implement other methods similarly
}

impl Cache for MyCache {
    // Implement the methods here, usually using getter queries
}

Required Associated Types

The error type the backend returns, for example sqlx::Error

Required Methods

Set or replace the current user information of the bot

Add or replace a channel in the cache

Remove a channel from the cache

Add a permission overwrite to the cache

Remove a channel’s permission overwrites from the cache

This should be something like DELETE FROM channel_overwrites WHERE channel_id = ?

Remove a guild’s channels from the cache

This should be something like DELETE FROM channels WHERE guild_id = ?

Add a DM channel to the cache, both of the IDs are unique

Add or replace a guild in the cache

Remove a channel from the cache

Add or replace an emoji in the cache

Remove an emoji from the cache

Remove a guild’s emojis from the cache

This should be something like DELETE FROM emojis WHERE guild_id = ?

Add or replace a sticker in the cache

Remove a sticker from the cache

Remove a guild’s stickers from the cache

This should be something like DELETE FROM stickers WHERE guild_id = ?

Add or replace a member in the cache

Remove a member from the cache

Remove a guild’s stickers from the cache

This should be something like DELETE FROM members WHERE guild_id = ?

Add or replace a message in the cache

Remove a message from the cache

Add an embed to the cache, the embed ID is unique

Remove an embed from the cache

Add an embed field to the cache, the embed ID is not unique

Remove an embed’s fields from the cache

This should be something like DELETE FROM embed_fields WHERE embed_id = ?

Get embeds of a message by its ID

This method is used internally in super::Cache::embeds

Get fields of an embed by its ID

This method is used internally in super::Cache::embeds

Add an attachment to the cache, the message ID is not unique

Remove a message’s attachments from the cache

This should be something like DELETE FROM attachments WHERE message_id = ?

Add or replace a message sticker in the cache

Remove a message’s stickers from the cache

This should be something like DELETE FROM message_stickers WHERE message_id = ?

Add or replace a presence in the cache

Remove a presence from the cache

Remove a guild’s presences from the cache

This should be something like DELETE FROM presences WHERE guild_id = ?

Add an activity to the cache, none of the activity’s IDs are unique

Remove a user’s activities from the cache

This should be something like DELETE FROM activities WHERE user_id = ?

Add a reaction to the cache, only the combination of message ID, user ID and emoji is unique, they’re not unique on their own

Remove a reaction from the cache

Remove a message’s reactions of the given emoji from the cache

This should be something like DELETE FROM reactions WHERE message_id = ? AND emoji = ?

Remove a message’s reactions from the cache

This should be something like DELETE FROM reactions WHERE message_id = ?

Add or update a role to the cache, only the combination of role ID and user ID is unique, they’re not unique on their own

When updating roles, make sure the user IDs remain untouched

Remove a role from the cache

Remove a guild’s roles from the cache

This should be something like DELETE FROM roles WHERE guild_id = ?

Remove a member’s roles from the cache

This should be something like DELETE FROM roles WHERE guild_id = ? AND user_id = ?

Add or replace a stage instance in the cache

Remove a stage instance from the cache

Remove a guild’s stage instance from the cache

This should be something like DELETE FROM stage_instances WHERE guild_id = ?

Implementors