global: reused + mempool + favicon

crates/brk_rpc/src/backend/bitcoincore.rs

@@ -1,13 +1,19 @@
 use std::{thread::sleep, time::Duration};
 
-use bitcoincore_rpc::{Client as CoreClient, Error as RpcError, RpcApi, jsonrpc};
+use bitcoincore_rpc::{
+    Client as CoreClient, Error as RpcError, RpcApi,
+    json::{GetBlockTemplateCapabilities, GetBlockTemplateModes, GetBlockTemplateRules},
+    jsonrpc,
+};
 use brk_error::{Error, Result};
-use brk_types::Sats;
+use brk_types::{Sats, Txid};
 use parking_lot::RwLock;
 use serde_json::value::RawValue;
 use tracing::info;
 
-use super::{Auth, BlockHeaderInfo, BlockInfo, BlockchainInfo, RawMempoolEntry, TxOutInfo};
+use super::{
+    Auth, BlockHeaderInfo, BlockInfo, BlockTemplateTx, BlockchainInfo, RawMempoolEntry, TxOutInfo,
+};
 
 /// Per-batch request count for `get_block_hashes_range`. Sized so the
 /// JSON request body stays well under a megabyte and bitcoind doesn't
@@ -310,4 +316,23 @@ impl ClientInner {
     pub fn send_raw_transaction(&self, hex: &str) -> Result<bitcoin::Txid> {
         Ok(self.call_once(|c| c.send_raw_transaction(hex))?)
     }
+
+    /// Transactions Bitcoin Core would include in the next block it would
+    /// mine. Core requires the `segwit` rule to be declared.
+    pub fn get_block_template_txs(&self) -> Result<Vec<BlockTemplateTx>> {
+        let r = self.call_with_retry(|c| {
+            c.get_block_template(
+                GetBlockTemplateModes::Template,
+                &[GetBlockTemplateRules::SegWit],
+                &[] as &[GetBlockTemplateCapabilities],
+            )
+        })?;
+        Ok(r.transactions
+            .into_iter()
+            .map(|t| BlockTemplateTx {
+                txid: Txid::from(t.txid),
+                fee: Sats::from(t.fee.to_sat()),
+            })
+            .collect())
+    }
 }

crates/brk_rpc/src/backend/corepc.rs

@@ -1,13 +1,15 @@
 use std::{thread::sleep, time::Duration};
 
 use brk_error::{Error, Result};
-use brk_types::Sats;
+use brk_types::{Sats, Txid};
 use corepc_client::client_sync::Auth as CorepcAuth;
 use parking_lot::RwLock;
 use serde_json::value::RawValue;
 use tracing::info;
 
-use super::{Auth, BlockHeaderInfo, BlockInfo, BlockchainInfo, RawMempoolEntry, TxOutInfo};
+use super::{
+    Auth, BlockHeaderInfo, BlockInfo, BlockTemplateTx, BlockchainInfo, RawMempoolEntry, TxOutInfo,
+};
 
 type CoreClient = corepc_client::client_sync::v30::Client;
 type CoreError = corepc_client::client_sync::Error;
@@ -186,11 +188,7 @@ impl ClientInner {
     /// a 50 MB request body or hold every response in memory at once.
     ///
     /// Returns hashes in canonical order (`start`, `start+1`, …, `end`).
-    pub fn get_block_hashes_range(
-        &self,
-        start: u64,
-        end: u64,
-    ) -> Result<Vec<bitcoin::BlockHash>> {
+    pub fn get_block_hashes_range(&self, start: u64, end: u64) -> Result<Vec<bitcoin::BlockHash>> {
         if end < start {
             return Ok(Vec::new());
         }
@@ -370,6 +368,22 @@ impl ClientInner {
             c.call("sendrawtransaction", &args)
         })?)
     }
+
+    /// Transactions Bitcoin Core would include in the next block it would
+    /// mine. Core requires the `segwit` rule to be declared.
+    pub fn get_block_template_txs(&self) -> Result<Vec<BlockTemplateTx>> {
+        let args = [serde_json::json!({ "rules": ["segwit"] })];
+        let r: GetBlockTemplateResponse =
+            self.call_with_retry(|c| c.call("getblocktemplate", &args))?;
+
+        Ok(r.transactions
+            .into_iter()
+            .map(|t| BlockTemplateTx {
+                txid: Txid::from(t.txid),
+                fee: Sats::from(t.fee),
+            })
+            .collect())
+    }
 }
 
 // Local deserialization structs for raw RPC responses
@@ -386,3 +400,14 @@ struct TxOutResponse {
 struct TxOutScriptPubKey {
     hex: String,
 }
+
+#[derive(serde::Deserialize)]
+struct GetBlockTemplateResponse {
+    transactions: Vec<GetBlockTemplateTx>,
+}
+
+#[derive(serde::Deserialize)]
+struct GetBlockTemplateTx {
+    txid: bitcoin::Txid,
+    fee: u64,
+}

crates/brk_rpc/src/backend/mod.rs

@@ -1,7 +1,7 @@
 use std::path::PathBuf;
 
 use bitcoin::ScriptBuf;
-use brk_types::Sats;
+use brk_types::{Sats, Txid};
 
 #[derive(Debug, Clone)]
 pub struct BlockchainInfo {
@@ -29,6 +29,12 @@ pub struct TxOutInfo {
     pub script_pub_key: ScriptBuf,
 }
 
+#[derive(Debug, Clone)]
+pub struct BlockTemplateTx {
+    pub txid: Txid,
+    pub fee: Sats,
+}
+
 #[derive(Debug, Clone)]
 pub struct RawMempoolEntry {
     pub vsize: u64,

crates/brk_rpc/src/lib.rs

@@ -12,7 +12,7 @@ use brk_types::{BlockHash, Height, MempoolEntryInfo, Sats, Txid, Vout};
 
 pub mod backend;
 
-pub use backend::{Auth, BlockHeaderInfo, BlockInfo, BlockchainInfo, TxOutInfo};
+pub use backend::{Auth, BlockHeaderInfo, BlockInfo, BlockTemplateTx, BlockchainInfo, TxOutInfo};
 
 use backend::ClientInner;
 use tracing::{debug, info};
@@ -201,6 +201,12 @@ impl Client {
         self.0.send_raw_transaction(hex).map(Txid::from)
     }
 
+    /// Transactions (txid + fee) Bitcoin Core would include in the next
+    /// block it would mine, via `getblocktemplate`.
+    pub fn get_block_template_txs(&self) -> Result<Vec<BlockTemplateTx>> {
+        self.0.get_block_template_txs()
+    }
+
     /// Checks if a block is in the main chain (has positive confirmations)
     pub fn is_in_main_chain(&self, hash: &BlockHash) -> Result<bool> {
         let block_info = self.get_block_info(hash)?;