liquid: make the server work with custom initial issuance prevout (generic test chain with same parameters of testnet)

Author: enaples

src/config.rs

@@ -8,6 +8,8 @@ use std::sync::Arc;
 use stderrlog;
 
 use crate::chain::Network;
+#[cfg(feature = "liquid")]
+use crate::chain::Txid;
 use crate::daemon::CookieGetter;
 use crate::errors::*;
 
@@ -81,6 +83,8 @@ pub struct Config {
     pub parent_network: BNetwork,
     #[cfg(feature = "liquid")]
     pub asset_db_path: Option<PathBuf>,
+    #[cfg(feature = "liquid")]
+    pub initial_issuance_prevtx: Option<Txid>,
 
     #[cfg(feature = "electrum-discovery")]
     pub electrum_public_hosts: Option<crate::electrum::ServerHosts>,
@@ -295,6 +299,12 @@ impl Config {
                     .long("asset-db-path")
                     .help("Directory for liquid/elements asset db")
                     .takes_value(true),
+            )
+            .arg(
+                Arg::with_name("initial_issuance_prevtx")
+                    .long("initial-issuance-prevtx")
+                    .help("Custom initial issuance prevtx TXID — the txid spent by the issuance tx's input (required for custom liquid testnets/signets)")
+                    .takes_value(true),
             );
 
         #[cfg(feature = "electrum-discovery")]
@@ -334,6 +344,12 @@ impl Config {
         #[cfg(feature = "liquid")]
         let asset_db_path = m.value_of("asset_db_path").map(PathBuf::from);
 
+        #[cfg(feature = "liquid")]
+        let initial_issuance_prevtx = m.value_of("initial_issuance_prevtx").map(|s| {
+            s.parse::<Txid>()
+                .expect("invalid initial-issuance-prevtx TXID")
+        });
+
         let default_daemon_port = match network_type {
             #[cfg(not(feature = "liquid"))]
             Network::Bitcoin => 8332,
@@ -516,6 +532,8 @@ impl Config {
             parent_network,
             #[cfg(feature = "liquid")]
             asset_db_path,
+            #[cfg(feature = "liquid")]
+            initial_issuance_prevtx,
 
             #[cfg(feature = "electrum-discovery")]
             electrum_public_hosts,
@@ -524,6 +542,7 @@ impl Config {
             #[cfg(feature = "electrum-discovery")]
             tor_proxy: m.value_of("tor_proxy").map(|s| s.parse().unwrap()),
         };
+
         eprintln!("{:?}", config);
         config
     }

src/new_index/schema.rs

@@ -109,6 +109,18 @@ impl Store {
             HeaderList::empty()
         };
 
+        #[cfg(feature = "liquid")]
+        if let Some(prevtx) = config.initial_issuance_prevtx {
+            // Seed a dummy zero-value txo so the indexer can resolve the
+            // initial issuance input via a normal lookup, instead of a
+            // special-case in has_prevout(). See issue #125.
+            let outpoint = OutPoint { txid: prevtx, vout: 0 };
+            let key = TxOutRow::key(&outpoint);
+            if txstore_db.get(&key).is_none() {
+                txstore_db.put(&key, &serialize(&TxOut::default()));
+            }
+        }
+
         Store {
             txstore_db,
             history_db,

src/util/transaction.rs

@@ -5,11 +5,11 @@ use std::collections::{BTreeSet, HashMap};
 
 #[cfg(feature = "liquid")]
 lazy_static! {
-    static ref REGTEST_INITIAL_ISSUANCE_PREVOUT: Txid =
+    static ref REGTEST_INITIAL_ISSUANCE_PREVTX: Txid =
         "50cdc410c9d0d61eeacc531f52d2c70af741da33af127c364e52ac1ee7c030a5"
             .parse()
             .unwrap();
-    static ref TESTNET_INITIAL_ISSUANCE_PREVOUT: Txid =
+    static ref TESTNET_INITIAL_ISSUANCE_PREVTX: Txid =
         "0c52d2526a5c9f00e9fb74afd15dd3caaf17c823159a514f929ae25193a43a52"
             .parse()
             .unwrap();
@@ -80,8 +80,8 @@ pub fn has_prevout(txin: &TxIn) -> bool {
     #[cfg(feature = "liquid")]
     return !txin.is_coinbase()
         && !txin.is_pegin
-        && txin.previous_output.txid != *REGTEST_INITIAL_ISSUANCE_PREVOUT
-        && txin.previous_output.txid != *TESTNET_INITIAL_ISSUANCE_PREVOUT;
+        && txin.previous_output.txid != *REGTEST_INITIAL_ISSUANCE_PREVTX
+        && txin.previous_output.txid != *TESTNET_INITIAL_ISSUANCE_PREVTX;
 }
 
 pub fn is_spendable(txout: &TxOut) -> bool {
@@ -203,4 +203,4 @@ mod test {
             Some(value)
         );
     }
-}
+}