Trait TopicStore 

pub trait TopicStore<T, A, D> {
    type Error: Error;

    // Required methods
    fn associate(
        &self,
        topic: &T,
        author: &A,
        data_id: &D,
    ) -> impl Future<Output = Result<bool, Self::Error>>;
    fn remove(
        &self,
        topic: &T,
        author: &A,
        data_id: &D,
    ) -> impl Future<Output = Result<bool, Self::Error>>;
    fn resolve(
        &self,
        topic: &T,
    ) -> impl Future<Output = Result<BTreeMap<A, Vec<D>>, Self::Error>>;
}

Maps a topic to a user-defined data type being sent over the wire during sync.

It defines the type of data it is expecting to sync and how the scope for a particular session should be identified; users provide an implementation of the TopicStore trait in order to define how this mapping occurs.

Since TopicStore is generic we can use the same mapping across different sync implementations for the same data type when necessary.

For example a TopicStore map implementation could map a generic T to a set of logs.

Designing TopicStore for applications

Considering an example chat application which is based on append-only log data types, we probably want to organise messages from an author for a certain chat group into one log each. Like this, a chat group can be expressed as a collection of one to potentially many logs (one per member of the group):

All authors: A, B and C
All chat groups: 1 and 2

"Chat group 1 with members A and B"
- Log A1
- Log B1

"Chat group 2 with members A, B and C"
- Log A2
- Log B2
- Log C2

If we implement T to express that we’re interested in syncing over a specific chat group, for example “Chat Group 2” we would implement TopicStore to give us all append-only logs of all members inside this group, that is the entries inside logs A2, B2 and C2.

Required Associated Types

type Error: Error

Required Methods

fn associate( &self, topic: &T, author: &A, data_id: &D, ) -> impl Future<Output = Result<bool, Self::Error>>

Associate an author and data id pair with a topic.

fn remove( &self, topic: &T, author: &A, data_id: &D, ) -> impl Future<Output = Result<bool, Self::Error>>

Remove an association with a topic.

fn resolve( &self, topic: &T, ) -> impl Future<Output = Result<BTreeMap<A, Vec<D>>, Self::Error>>

Retrieve all associations for the provided topic.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<T, L> TopicStore<T, VerifyingKey, L> for SqliteStore

where T: Serialize + for<'de> Deserialize<'de>, L: LogId,

Available on crate feature sqlite only.

SQLite TopicStore implementation that can be used to map a topic to a set of (generic) per-author data identifiers.

type Error = SqliteError