hotshot_query_service/data_source/fetching/
transaction.rs

1// Copyright (c) 2022 Espresso Systems (espressosys.com)
2// This file is part of the HotShot Query Service library.
3//
4// This program is free software: you can redistribute it and/or modify it under the terms of the GNU
5// General Public License as published by the Free Software Foundation, either version 3 of the
6// License, or (at your option) any later version.
7// This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
8// even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
9// General Public License for more details.
10// You should have received a copy of the GNU General Public License along with this program. If not,
11// see <https://www.gnu.org/licenses/>.
12
13//! Transaction fetching.
14
15use std::sync::Arc;
16
17use async_trait::async_trait;
18use derive_more::From;
19use futures::future::{BoxFuture, FutureExt};
20use hotshot_types::traits::node_implementation::NodeType;
21
22use super::{AvailabilityProvider, FetchRequest, Fetchable, Fetcher, Notifiers};
23use crate::{
24    availability::{BlockWithTransaction, QueryableHeader, QueryablePayload, TransactionHash},
25    data_source::{
26        storage::{
27            pruning::PrunedHeightStorage, AvailabilityStorage, NodeStorage,
28            UpdateAvailabilityStorage,
29        },
30        update::VersionedDataSource,
31    },
32    types::HeightIndexed,
33    Header, Payload, QueryError, QueryResult,
34};
35
36#[derive(Clone, Copy, Debug, From)]
37pub(super) struct TransactionRequest<Types: NodeType>(TransactionHash<Types>);
38
39impl<Types: NodeType> FetchRequest for TransactionRequest<Types> {}
40
41#[async_trait]
42impl<Types> Fetchable<Types> for BlockWithTransaction<Types>
43where
44    Types: NodeType,
45    Header<Types>: QueryableHeader<Types>,
46    Payload<Types>: QueryablePayload<Types>,
47{
48    type Request = TransactionRequest<Types>;
49
50    fn satisfies(&self, req: Self::Request) -> bool {
51        req.0 == self.transaction.hash()
52    }
53
54    async fn passive_fetch(
55        notifications: &Notifiers<Types>,
56        req: Self::Request,
57    ) -> BoxFuture<'static, Option<Self>> {
58        // Any block might satisfy the request; we won't know until we receive a new payload and
59        // check if it contains the desired transaction.
60        let wait_block = notifications
61            .block
62            .wait_for(move |block| block.transaction_by_hash(req.0).is_some())
63            .await;
64
65        async move {
66            let block = wait_block.await?;
67            BlockWithTransaction::with_hash(block, req.0)
68        }
69        .boxed()
70    }
71
72    async fn active_fetch<S, P>(
73        _tx: &mut impl AvailabilityStorage<Types>,
74        _fetcher: Arc<Fetcher<Types, S, P>>,
75        req: Self::Request,
76    ) -> anyhow::Result<()>
77    where
78        S: VersionedDataSource + 'static,
79        for<'a> S::Transaction<'a>: UpdateAvailabilityStorage<Types>,
80        for<'a> S::ReadOnly<'a>:
81            AvailabilityStorage<Types> + NodeStorage<Types> + PrunedHeightStorage,
82        P: AvailabilityProvider<Types>,
83    {
84        // We don't actively fetch transactions, because without a satisfying block payload, we have
85        // no way of knowing whether a block with such a transaction actually exists, and we don't
86        // want to bother peers with requests for non-existent transactions.
87        tracing::debug!("not fetching unknown transaction {req:?}");
88        Ok(())
89    }
90
91    async fn load<S>(storage: &mut S, req: Self::Request) -> QueryResult<Self>
92    where
93        S: AvailabilityStorage<Types>,
94    {
95        let hash = req.0;
96        let block = storage.get_block_with_transaction(hash).await?;
97        let height = block.height();
98        BlockWithTransaction::with_hash(block, hash).ok_or(QueryError::Error {
99            message: format!(
100                "transaction index inconsistent: block {height} contains no transaction {hash}"
101            ),
102        })
103    }
104}
hotshot_query_service/data_source/fetching/transaction.rs

hotshot_query_service/data_source/fetching/
transaction.rs
