feat: Add endpoint for total supply

Total supply is defined as liquid supply plus timelocked supply.

src/lib.rs

@@ -4,3 +4,4 @@ pub mod http_util;
 pub mod model;
 pub mod neptune_rpc;
 pub mod rpc;
+pub mod shared;

src/main.rs

@@ -16,6 +16,7 @@ use neptune_explorer::rpc::block_info::block_info;
 use neptune_explorer::rpc::circulating_supply::circulating_supply;
 use neptune_explorer::rpc::pow_puzzle::pow_puzzle;
 use neptune_explorer::rpc::provide_pow_solution::provide_pow_solution;
+use neptune_explorer::rpc::total_supply::total_supply;
 use neptune_explorer::rpc::utxo_digest::utxo_digest;
 use tower_http::services::ServeDir;
 use tracing::info;
@@ -60,6 +61,7 @@ pub fn setup_routes(app_state: AppState) -> Router {
         .route("/rpc/utxo_digest/:index", get(utxo_digest))
         .route("/rpc/pow_puzzle/*address", get(pow_puzzle))
         .route("/rpc/circulating_supply", get(circulating_supply))
+        .route("/rpc/total_supply", get(total_supply))
         .route("/rpc/provide_pow_solution", post(provide_pow_solution))
         // -- Dynamic HTML pages --
         .route("/", get(root))

src/rpc/circulating_supply.rs

@@ -3,67 +3,28 @@ use std::sync::Arc;
 use axum::extract::State;
 use axum::response::Json;
 use axum::response::Response;
-use neptune_cash::api::export::BlockHeight;
-use neptune_cash::protocol::consensus::block::block_height::BLOCKS_PER_GENERATION;
-use neptune_cash::protocol::consensus::block::block_height::NUM_BLOCKS_SKIPPED_BECAUSE_REBOOT;
-use neptune_cash::protocol::consensus::block::Block;
-use neptune_cash::protocol::consensus::block::PREMINE_MAX_SIZE;
 use tarpc::context;
 
 use crate::http_util::rpc_err;
 use crate::http_util::rpc_method_err;
 use crate::model::app_state::AppState;
+use crate::shared::monetary_supplies;
 
-/// Return the number of coins that are liquid, assuming all redemptions on the
-/// old chain have successfully been made.
+/// Return the monetary amount that is liquid, assuming all redemptions on the
+/// old chain have successfully been made. Returned unit is nau, Neptune Atomic
+/// Units. To convert to number of coins, divide by $4*10^{30}$.
 #[axum::debug_handler]
 pub async fn circulating_supply(State(state): State<Arc<AppState>>) -> Result<Json<f64>, Response> {
     let s = state.load();
 
-    // TODO: Remove this local declaration once version of neptune-core with
-    // this value public is released.
-    let generation_0_subsidy = Block::block_subsidy(BlockHeight::genesis().next());
-    let block_height: u64 = s
+    let block_height = s
         .rpc_client
         .block_height(context::current(), s.token())
         .await
         .map_err(rpc_err)?
-        .map_err(rpc_method_err)?
-        .into();
-    let effective_block_height = block_height + NUM_BLOCKS_SKIPPED_BECAUSE_REBOOT;
-    let (num_generations, num_blocks_in_generation): (u64, u32) = (
-        effective_block_height / BLOCKS_PER_GENERATION,
-        (effective_block_height % BLOCKS_PER_GENERATION)
-            .try_into()
-            .expect("There are fewer than u32::MAX blocks per generation"),
-    );
+        .map_err(rpc_method_err)?;
 
-    let mut liquid_supply = PREMINE_MAX_SIZE;
-    let mut liquid_subsidy = generation_0_subsidy.half();
-    let blocks_per_generation: u32 = BLOCKS_PER_GENERATION
-        .try_into()
-        .expect("There are fewer than u32::MAX blocks per generation");
-    for _ in 0..num_generations {
-        liquid_supply += liquid_subsidy.scalar_mul(blocks_per_generation);
-        liquid_subsidy = liquid_subsidy.half();
-    }
-
-    liquid_supply += liquid_subsidy.scalar_mul(num_blocks_in_generation);
-
-    // How much of timelocked miner rewards have been unlocked? Assume that the
-    // timelock is exactly one generation long. In reality the timelock is
-    // is defined in relation to timestamp and not block heights, so this is
-    // only a (pretty good) approximation.
-
-    let mut released_subsidy = generation_0_subsidy.half();
-    for _ in 1..num_generations {
-        liquid_supply += released_subsidy.scalar_mul(blocks_per_generation);
-        released_subsidy = released_subsidy.half();
-    }
-
-    if num_generations > 0 {
-        liquid_supply += released_subsidy.scalar_mul(num_blocks_in_generation);
-    }
+    let (liquid_supply, _) = monetary_supplies(block_height);
 
     Ok(Json(liquid_supply.to_nau_f64()))
 }

src/rpc/mod.rs

@@ -3,4 +3,5 @@ pub mod block_info;
 pub mod circulating_supply;
 pub mod pow_puzzle;
 pub mod provide_pow_solution;
+pub mod total_supply;
 pub mod utxo_digest;

src/rpc/total_supply.rs

@@ -0,0 +1,31 @@
+use std::sync::Arc;
+
+use axum::extract::State;
+use axum::response::Json;
+use axum::response::Response;
+use tarpc::context;
+
+use crate::http_util::rpc_err;
+use crate::http_util::rpc_method_err;
+use crate::model::app_state::AppState;
+use crate::shared::monetary_supplies;
+
+/// Return the total monetary supply, the sum of the timeloced and liquid
+/// supply. Assumes all redemptions on the old chain have successfully been
+/// made. Returned unit is nau, Neptune Atomic Units. To convert to number of
+/// coins, divide by $4*10^{30}$.
+#[axum::debug_handler]
+pub async fn total_supply(State(state): State<Arc<AppState>>) -> Result<Json<f64>, Response> {
+    let s = state.load();
+
+    let block_height = s
+        .rpc_client
+        .block_height(context::current(), s.token())
+        .await
+        .map_err(rpc_err)?
+        .map_err(rpc_method_err)?;
+
+    let (_, total_supply) = monetary_supplies(block_height);
+
+    Ok(Json(total_supply.to_nau_f64()))
+}

src/shared.rs

@@ -0,0 +1,60 @@
+use neptune_cash::api::export::BlockHeight;
+use neptune_cash::api::export::NativeCurrencyAmount;
+use neptune_cash::protocol::consensus::block::block_height::BLOCKS_PER_GENERATION;
+use neptune_cash::protocol::consensus::block::block_height::NUM_BLOCKS_SKIPPED_BECAUSE_REBOOT;
+use neptune_cash::protocol::consensus::block::Block;
+use neptune_cash::protocol::consensus::block::PREMINE_MAX_SIZE;
+
+/// Return the pair (liquid supply, total supply)
+///
+/// Assumes all redemption claims have been rewarded.
+pub(crate) fn monetary_supplies(
+    block_height: BlockHeight,
+) -> (NativeCurrencyAmount, NativeCurrencyAmount) {
+    let block_height: u64 = block_height.into();
+    let generation_0_subsidy = Block::block_subsidy(BlockHeight::genesis().next());
+    let effective_block_height = block_height + NUM_BLOCKS_SKIPPED_BECAUSE_REBOOT;
+    let (num_generations, num_blocks_in_curr_gen): (u64, u32) = (
+        effective_block_height / BLOCKS_PER_GENERATION,
+        (effective_block_height % BLOCKS_PER_GENERATION)
+            .try_into()
+            .expect("There are fewer than u32::MAX blocks per generation"),
+    );
+
+    let mut liquid_supply = PREMINE_MAX_SIZE;
+    let mut liquid_subsidy = generation_0_subsidy.half();
+    let mut total_supply = PREMINE_MAX_SIZE;
+    let blocks_per_generation: u32 = BLOCKS_PER_GENERATION
+        .try_into()
+        .expect("There are fewer than u32::MAX blocks per generation");
+    for _ in 0..num_generations {
+        liquid_supply += liquid_subsidy.scalar_mul(blocks_per_generation);
+        total_supply += liquid_subsidy.scalar_mul(2);
+        liquid_subsidy = liquid_subsidy.half();
+    }
+
+    let liquid_supply_current_generation = liquid_subsidy.scalar_mul(num_blocks_in_curr_gen);
+    liquid_supply += liquid_supply_current_generation;
+    total_supply += liquid_supply_current_generation.scalar_mul(2);
+
+    // How much of timelocked miner rewards have been unlocked? Assume that the
+    // timelock is exactly one generation long. In reality the timelock is
+    // is defined in relation to timestamp and not block heights, so this is
+    // only a (good) approximation.
+
+    let mut released_subsidy = generation_0_subsidy.half();
+    for _ in 1..num_generations {
+        liquid_supply += released_subsidy.scalar_mul(blocks_per_generation);
+        released_subsidy = released_subsidy.half();
+    }
+
+    if num_generations > 0 {
+        liquid_supply += released_subsidy.scalar_mul(num_blocks_in_curr_gen);
+    }
+
+    // If you want correct results for anything but main net, and claims are
+    // only being refunded on main net, the size of the claims pool must be
+    // subtracted here, if that the network is not main net.
+
+    (liquid_supply, total_supply)
+}