get_output_distribution

binaries/cuprated/src/rpc/request/blockchain.rs

@@ -14,9 +14,11 @@ use cuprate_helper::cast::{u64_to_usize, usize_to_u64};
 use cuprate_types::{
     blockchain::{BlockchainReadRequest, BlockchainResponse},
     rpc::{
-        ChainInfo, CoinbaseTxSum, KeyImageSpentStatus, OutputHistogramEntry, OutputHistogramInput,
+        ChainInfo, CoinbaseTxSum, KeyImageSpentStatus, OutputDistributionData,
+        OutputHistogramEntry, OutputHistogramInput,
     },
-    BlockCompleteEntry, Chain, ExtendedBlockHeader, OutputOnChain, TxInBlockchain,
+    BlockCompleteEntry, Chain, ExtendedBlockHeader, OutputDistributionInput, OutputOnChain,
+    TxInBlockchain,
 };
 
 /// [`BlockchainReadRequest::Block`].
@@ -308,6 +310,23 @@ pub(crate) async fn database_size(
     Ok((database_size, free_space))
 }
 
+/// [`BlockchainReadRequest::OutputDistribution`]
+pub(crate) async fn output_distribution(
+    blockchain_read: &mut BlockchainReadHandle,
+    input: OutputDistributionInput,
+) -> Result<Vec<OutputDistributionData>, Error> {
+    let BlockchainResponse::OutputDistribution(data) = blockchain_read
+        .ready()
+        .await?
+        .call(BlockchainReadRequest::OutputDistribution(input))
+        .await?
+    else {
+        unreachable!();
+    };
+
+    Ok(data)
+}
+
 /// [`BlockchainReadRequest::OutputHistogram`]
 pub(crate) async fn output_histogram(
     blockchain_read: &mut BlockchainReadHandle,

binaries/cuprated/src/rpc/shared.rs

@@ -1,8 +1,12 @@
 //! RPC handler functions that are shared between different endpoint/methods.
 
-use std::collections::{HashMap, HashSet};
+use std::{
+    collections::{HashMap, HashSet},
+    num::NonZero,
+};
 
 use anyhow::{anyhow, Error};
+use cuprate_types::OutputDistributionInput;
 use monero_serai::transaction::Timelock;
 
 use cuprate_constants::rpc::MAX_RESTRICTED_GLOBAL_FAKE_OUTS_COUNT;
@@ -97,36 +101,35 @@ pub(super) async fn get_transaction_pool_hashes(
 /// <https://github.com/monero-project/monero/blob/cc73fe71162d564ffda8e549b79a350bca53c454/src/rpc/core_rpc_server.cpp#L3352-L3398>
 ///
 /// Shared between:
-/// - JSON-RPC's `get_output_distribution`
+/// - Other JSON's `/get_output_distribution`
 /// - Binary's `/get_output_distribution.bin`
+///
+/// Returns transaction hashes.
 pub(super) async fn get_output_distribution(
     mut state: CupratedRpcHandler,
     request: GetOutputDistributionRequest,
 ) -> Result<GetOutputDistributionResponse, Error> {
-    if state.is_restricted() && request.amounts != [1, 0] {
+    if state.is_restricted() && request.amounts != [0] {
         return Err(anyhow!(
             "Restricted RPC can only get output distribution for RCT outputs. Use your own node."
         ));
     }
 
-    // 0 is placeholder for the whole chain
-    let req_to_height = if request.to_height == 0 {
-        helper::top_height(&mut state).await?.0.saturating_sub(1)
-    } else {
-        request.to_height
+    let input = OutputDistributionInput {
+        amounts: request.amounts,
+        cumulative: request.cumulative,
+        from_height: request.from_height,
+
+        // 0 / `None` is placeholder for the whole chain
+        to_height: NonZero::new(request.to_height),
     };
 
-    let distributions = request.amounts.into_iter().map(|amount| {
-        fn get_output_distribution() -> Result<Distribution, Error> {
-            todo!("https://github.com/monero-project/monero/blob/893916ad091a92e765ce3241b94e706ad012b62a/src/rpc/rpc_handler.cpp#L29");
-            Err(anyhow!("Failed to get output distribution"))
-        }
-
-        get_output_distribution()
-    }).collect::<Result<Vec<Distribution>, _>>()?;
+    let distributions = blockchain::output_distribution(&mut state.blockchain_read, input).await?;
 
     Ok(GetOutputDistributionResponse {
         base: helper::access_response_base(false),
-        distributions,
+        distributions: todo!(
+            "This type contains binary strings: <https://github.com/monero-project/monero/issues/9422>"
+        ),
     })
 }

rpc/interface/src/route/json_rpc.rs

@@ -1,15 +1,10 @@
 //! JSON-RPC 2.0 endpoint route functions.
 
 //---------------------------------------------------------------------------------------------------- Import
-use std::borrow::Cow;
-
 use axum::{extract::State, http::StatusCode, Json};
 use tower::ServiceExt;
 
-use cuprate_json_rpc::{
-    error::{ErrorCode, ErrorObject},
-    Id, Response,
-};
+use cuprate_json_rpc::{Id, Response};
 use cuprate_rpc_types::{
     json::{JsonRpcRequest, JsonRpcResponse},
     RpcCallValue,

storage/blockchain/src/service/read.rs

@@ -30,7 +30,7 @@ use cuprate_helper::map::combine_low_high_bits_to_u128;
 use cuprate_types::{
     blockchain::{BlockchainReadRequest, BlockchainResponse},
     rpc::OutputHistogramInput,
-    Chain, ChainId, ExtendedBlockHeader, OutputOnChain, TxsInBlock,
+    Chain, ChainId, ExtendedBlockHeader, OutputDistributionInput, OutputOnChain, TxsInBlock,
 };
 
 use crate::{
@@ -142,6 +142,7 @@ fn map_request(
         R::Transactions { tx_hashes } => transactions(env, tx_hashes),
         R::TotalRctOutputs => total_rct_outputs(env),
         R::TxOutputIndexes { tx_hash } => tx_output_indexes(env, &tx_hash),
+        R::OutputDistribution(input) => output_distribution(env, input),
     }
 
     /* SOMEDAY: post-request handling, run some code for each request? */
@@ -832,3 +833,8 @@ fn tx_output_indexes(env: &ConcreteEnv, tx_hash: &[u8; 32]) -> ResponseResult {
 
     Ok(BlockchainResponse::TxOutputIndexes(o_indexes.0))
 }
+
+/// [`BlockchainReadRequest::OutputDistribution`]
+fn output_distribution(env: &ConcreteEnv, input: OutputDistributionInput) -> ResponseResult {
+    Ok(BlockchainResponse::OutputDistribution(todo!()))
+}

types/types/src/blockchain.rs

@@ -11,9 +11,12 @@ use std::{
 use monero_serai::block::Block;
 
 use crate::{
-    rpc::{ChainInfo, CoinbaseTxSum, OutputHistogramEntry, OutputHistogramInput},
+    rpc::{
+        ChainInfo, CoinbaseTxSum, OutputDistributionData, OutputHistogramEntry,
+        OutputHistogramInput,
+    },
     types::{Chain, ExtendedBlockHeader, OutputOnChain, TxsInBlock, VerifiedBlockInformation},
-    AltBlockInformation, BlockCompleteEntry, ChainId, TxInBlockchain,
+    AltBlockInformation, BlockCompleteEntry, ChainId, OutputDistributionInput, TxInBlockchain,
 };
 
 //---------------------------------------------------------------------------------------------------- ReadRequest
@@ -154,6 +157,12 @@ pub enum BlockchainReadRequest {
     /// TODO: document fields after impl.
     OutputHistogram(OutputHistogramInput),
 
+    /// Get the distribution for an output amount.
+    ///
+    /// - TODO: document fields after impl.
+    /// - TODO: <https://github.com/monero-project/monero/blob/893916ad091a92e765ce3241b94e706ad012b62a/src/rpc/rpc_handler.cpp#L29>
+    OutputDistribution(OutputDistributionInput),
+
     /// Get the coinbase amount and the fees amount for
     /// `N` last blocks starting at particular height.
     ///
@@ -352,6 +361,9 @@ pub enum BlockchainResponse {
         free_space: u64,
     },
 
+    /// Response to [`BlockchainReadRequest::OutputDistribution`].
+    OutputDistribution(Vec<OutputDistributionData>),
+
     /// Response to [`BlockchainReadRequest::OutputHistogram`].
     OutputHistogram(Vec<OutputHistogramEntry>),
 

types/types/src/lib.rs

@@ -24,9 +24,9 @@ pub use transaction_verification_data::{
     CachedVerificationState, TransactionVerificationData, TxVersion,
 };
 pub use types::{
-    AltBlockInformation, BlockTemplate, Chain, ChainId, ExtendedBlockHeader, OutputOnChain,
-    TxInBlockchain, TxInPool, TxRelayChecks, TxsInBlock, VerifiedBlockInformation,
-    VerifiedTransactionInformation,
+    AltBlockInformation, BlockTemplate, Chain, ChainId, ExtendedBlockHeader,
+    OutputDistributionInput, OutputOnChain, TxInBlockchain, TxInPool, TxRelayChecks, TxsInBlock,
+    VerifiedBlockInformation, VerifiedTransactionInformation,
 };
 
 //---------------------------------------------------------------------------------------------------- Feature-gated

types/types/src/rpc/types.rs

@@ -253,6 +253,7 @@ define_struct_and_impl_epee! {
         45..=50
     )]
     OutputDistributionData {
+        amount: u64,
         distribution: Vec<u64>,
         start_height: u64,
         base: u64,

types/types/src/types.rs

@@ -208,6 +208,17 @@ bitflags::bitflags! {
     }
 }
 
+/// Used in RPC's `get_output_distribution`.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct OutputDistributionInput {
+    pub amounts: Vec<u64>,
+    pub cumulative: bool,
+    pub from_height: u64,
+
+    /// [`None`] means the entire blockchain.
+    pub to_height: Option<NonZero<u64>>,
+}
+
 //---------------------------------------------------------------------------------------------------- Tests
 #[cfg(test)]
 mod test {