Estimate gas price API Endpoint

CHANGELOG.md

@@ -10,6 +10,7 @@ Description of the upcoming release here.
 
 ### Changed
 
+- [#1650](https://github.com/FuelLabs/fuel-core/pull/1650): Add api endpoint for getting estimates for future gas prices
 - [#1649](https://github.com/FuelLabs/fuel-core/pull/1649): Add api endpoint for getting latest gas price
 - [#1600](https://github.com/FuelLabs/fuel-core/pull/1640): Upgrade to fuel-vm 0.45.0
 - [#1633](https://github.com/FuelLabs/fuel-core/pull/1633): Notify services about importing of the genesis block.

crates/client/assets/schema.sdl

@@ -272,6 +272,10 @@ type DryRunTransactionExecutionStatus {
 
 union DryRunTransactionStatus = DryRunSuccessStatus | DryRunFailureStatus
 
+type EstimateGasPrice {
+	gasPrice: U64!
+}
+
 input ExcludeInput {
 	"""
 	Utxos to exclude from the selection.
@@ -812,6 +816,7 @@ type Query {
 	contractBalances(filter: ContractBalanceFilterInput!, first: Int, after: String, last: Int, before: String): ContractBalanceConnection!
 	nodeInfo: NodeInfo!
 	latestGasPrice: LatestGasPrice!
+	estimateGasPrice(blockHorizon: U32): EstimateGasPrice!
 	message(nonce: Nonce!): Message
 	messages(owner: Address, first: Int, after: String, last: Int, before: String): MessageConnection!
 	messageProof(transactionId: TransactionId!, nonce: Nonce!, commitBlockId: BlockId, commitBlockHeight: U32): MessageProof

crates/client/src/client.rs

@@ -6,6 +6,7 @@ use crate::client::{
             SpendQueryElementInput,
         },
         contract::ContractBalanceQueryArgs,
+        gas_price::EstimateGasPrice,
         message::MessageStatusArgs,
         tx::DryRunArg,
         Tai64Timestamp,
@@ -354,6 +355,14 @@ impl FuelClient {
         self.query(query).await.map(|r| r.latest_gas_price.into())
     }
 
+    pub async fn estimate_gas_price(
+        &self,
+        block_horizon: u32,
+    ) -> io::Result<EstimateGasPrice> {
+        let query = schema::gas_price::QueryEstimateGasPrice::build(block_horizon.into());
+        self.query(query).await.map(|r| r.estimate_gas_price)
+    }
+
     pub async fn connected_peers_info(&self) -> io::Result<Vec<PeerInfo>> {
         let query = schema::node_info::QueryPeersInfo::build(());
         self.query(query)

crates/client/src/client/schema/gas_price.rs

@@ -17,6 +17,36 @@ pub struct QueryLatestGasPrice {
     pub latest_gas_price: LatestGasPrice,
 }
 
+#[derive(cynic::QueryFragment, Debug)]
+#[cynic(schema_path = "./assets/schema.sdl")]
+pub struct EstimateGasPrice {
+    pub gas_price: U64,
+}
+
+#[derive(cynic::QueryVariables, Debug)]
+pub struct BlockHorizonArgs {
+    pub block_horizon: Option<U32>,
+}
+
+impl From<u32> for BlockHorizonArgs {
+    fn from(block_horizon: u32) -> Self {
+        Self {
+            block_horizon: Some(block_horizon.into()),
+        }
+    }
+}
+
+#[derive(cynic::QueryFragment, Debug)]
+#[cynic(
+    schema_path = "./assets/schema.sdl",
+    graphql_type = "Query",
+    variables = "BlockHorizonArgs"
+)]
+pub struct QueryEstimateGasPrice {
+    #[arguments(blockHorizon: $block_horizon)]
+    pub estimate_gas_price: EstimateGasPrice,
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -27,4 +57,12 @@ mod tests {
         let operation = QueryLatestGasPrice::build(());
         insta::assert_snapshot!(operation.query)
     }
+
+    #[test]
+    fn estimate_gas_price_query_gql_output() {
+        use cynic::QueryBuilder;
+        let arbitrary_horizon = 10;
+        let operation = QueryEstimateGasPrice::build(arbitrary_horizon.into());
+        insta::assert_snapshot!(operation.query)
+    }
 }

crates/client/src/client/schema/snapshots/fuel_core_client__client__schema__gas_price__tests__estimate_gas_price_query_gql_output.snap

@@ -0,0 +1,11 @@
+---
+source: crates/client/src/client/schema/gas_price.rs
+expression: operation.query
+---
+query($blockHorizon: U32) {
+  estimateGasPrice(blockHorizon: $blockHorizon) {
+    gasPrice
+  }
+}
+
+

crates/client/src/client/types/gas_price.rs

@@ -14,3 +14,15 @@ impl From<schema::gas_price::LatestGasPrice> for LatestGasPrice {
         }
     }
 }
+
+pub struct EstimateGasPrice {
+    pub gas_price: u64,
+}
+
+impl From<schema::gas_price::EstimateGasPrice> for EstimateGasPrice {
+    fn from(value: schema::gas_price::EstimateGasPrice) -> Self {
+        Self {
+            gas_price: value.gas_price.into(),
+        }
+    }
+}

crates/fuel-core/src/schema.rs

@@ -46,6 +46,7 @@ pub struct Query(
     contract::ContractBalanceQuery,
     node_info::NodeQuery,
     gas_price::LatestGasPriceQuery,
+    gas_price::EstimateGasPriceQuery,
     message::MessageQuery,
 );
 

crates/fuel-core/src/schema/gas_price.rs

@@ -52,3 +52,38 @@ impl LatestGasPriceQuery {
         })
     }
 }
+
+pub struct EstimateGasPrice {
+    pub gas_price: U64,
+}
+
+#[Object]
+impl EstimateGasPrice {
+    async fn gas_price(&self) -> U64 {
+        self.gas_price
+    }
+}
+
+#[derive(Default)]
+pub struct EstimateGasPriceQuery {}
+
+#[Object]
+impl EstimateGasPriceQuery {
+    async fn estimate_gas_price(
+        &self,
+        ctx: &Context<'_>,
+        #[graphql(
+            desc = "Number of blocks into the future to estimate the gas price for"
+        )]
+        block_horizon: Option<U32>,
+    ) -> async_graphql::Result<EstimateGasPrice> {
+        // TODO: implement dynamic calculation based on block horizon
+        //   https://github.com/FuelLabs/fuel-core/issues/1653
+        let _ = block_horizon;
+
+        let config = ctx.data_unchecked::<GraphQLConfig>();
+        let gas_price = config.min_gas_price.into();
+
+        Ok(EstimateGasPrice { gas_price })
+    }
+}

tests/tests/gas_price.rs

@@ -3,6 +3,7 @@ use fuel_core::service::{
     FuelService,
 };
 use fuel_core_client::client::{
+    schema::gas_price::EstimateGasPrice,
     types::gas_price::LatestGasPrice,
     FuelClient,
 };
@@ -16,3 +17,16 @@ async fn latest_gas_price() {
     let LatestGasPrice { gas_price, .. } = client.latest_gas_price().await.unwrap();
     assert_eq!(gas_price, node_config.txpool.min_gas_price);
 }
+
+#[tokio::test]
+async fn estimate_gas_price() {
+    let node_config = Config::local_node();
+    let srv = FuelService::new_node(node_config.clone()).await.unwrap();
+    let client = FuelClient::from(srv.bound_address);
+
+    let arbitrary_horizon = 10;
+
+    let EstimateGasPrice { gas_price } =
+        client.estimate_gas_price(arbitrary_horizon).await.unwrap();
+    assert_eq!(u64::from(gas_price), node_config.txpool.min_gas_price);
+}