From a0a3d4f9392e21f9e92fdc274c88fed6d0634794 Mon Sep 17 00:00:00 2001
From: Martin Habovstiak <martin.habovstiak@gmail.com>
Date: Tue, 4 Aug 2020 13:21:30 +0200
Subject: [PATCH] Add blockchain.transaction.get_confirmed_blockhash

This adds a new RPC method that enables users to fetch the block hash
for given txid. It can thus be used to emulate `txindex=1` as explained
in the related issue.

Closes #287
---
 src/query.rs | 5 +++++
 src/rpc.rs   | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/src/query.rs b/src/query.rs
index 3b9a945..b70aee4 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -431,6 +431,11 @@ impl Query {
             .gettransaction_raw(tx_hash, blockhash, verbose)
     }
 
+    pub fn get_confirmed_blockhash(&self, tx_hash: &Txid) -> Result<Value> {
+        let blockhash = self.lookup_confirmed_blockhash(tx_hash, None)?;
+        Ok(json!({ "block_hash": blockhash }))
+    }
+
     pub fn get_headers(&self, heights: &[usize]) -> Vec<HeaderEntry> {
         let _timer = self
             .duration
diff --git a/src/rpc.rs b/src/rpc.rs
index 03de786..41bbbc3 100644
--- a/src/rpc.rs
+++ b/src/rpc.rs
@@ -267,6 +267,11 @@ impl Connection {
         Ok(self.query.get_transaction(&tx_hash, verbose)?)
     }
 
+    fn blockchain_transaction_get_confirmed_blockhash(&self, params: &[Value]) -> Result<Value> {
+        let tx_hash = hash_from_value(params.get(0)).chain_err(|| "bad tx_hash")?;
+        self.query.get_confirmed_blockhash(&tx_hash)
+    }
+
     fn blockchain_transaction_get_merkle(&self, params: &[Value]) -> Result<Value> {
         let tx_hash = hash_from_value(params.get(0)).chain_err(|| "bad tx_hash")?;
         let height = usize_from_value(params.get(1), "height")?;
@@ -318,6 +323,7 @@ impl Connection {
             "blockchain.transaction.broadcast" => self.blockchain_transaction_broadcast(&params),
             "blockchain.transaction.get" => self.blockchain_transaction_get(&params),
             "blockchain.transaction.get_merkle" => self.blockchain_transaction_get_merkle(&params),
+            "blockchain.transaction.get_confirmed_blockhash" => self.blockchain_transaction_get_confirmed_blockhash(&params),
             "blockchain.transaction.id_from_pos" => {
                 self.blockchain_transaction_id_from_pos(&params)
             }