ranking-index

Installing

Add this in the Cargo.toml of your zome:

[dependencies]
hc_lib_ranking_index = {git = "https://github.com/holochain-open-dev/ranking-index", branch = "main", package = "hc_lib_ranking_index"}

Usage

1. Add a LinkType to your zome to use for the ranking index Path

#[hdk_link_types]
pub enum LinkTypes {
    Ranking
}

2. Define your index:

const MY_RANKING_INDEX: RankingIndex = RankingIndex {
    link_type: ScopedLinkType::try_from(LinkTypes::Ranking).unwrap(),
    index_interval: 3,
};

Here, the link_type identifies the index, so only entries ranked by this index will be returned with get_entry_ranking_chunk.

3. Add an entry to the index with create_entry_ranking:

#[derive(Serialize, Deserialize, Debug)]
pub struct RankEntryInput {
    pub ranking: i64,
    pub entry_hash: EntryHash,
}

#[hdk_extern]
pub fn create_entry_ranking(input: RankEntryInput) -> ExternResult<()> {
    MY_RANKING_INDEX.create_entry_ranking(input.entry_hash, input.ranking, None)
}

4. Get the ranking of entries with get_entry_ranking_chunk:

#[derive(Serialize, Deserialize, Debug)]
pub struct GetRankingInput {
    pub direction: GetRankingDirection,
    pub entry_count: usize,
    pub cursor: Option<GetRankingCursor>,
}


#[hdk_extern]
pub fn get_entry_ranking_chunk(input: GetRankingInput) -> ExternResult<EntryRanking> {
    MY_RANKING_INDEX.get_entry_ranking_chunk(input.direction, input.entry_count, input.cursor)
}

---

You can see a fully working example zome here.

Dev Setup

Enter the nix-shell by running nix-shell in the root folder of the repository..

Testing

Run the tests with:

sh run-tests.sh