rpc: scanblocks, add "completed" flag to the result obj

To tell the user whether the process was aborted or not.

Plus, as the process can be aborted prior to the end range,
have also changed the "to_height" result value to return the
last scanned block instead of the end range block.

Author: furszy

src/rpc/blockchain.cpp

@@ -2321,6 +2321,7 @@ static RPCHelpMan scanblocks()
                 {RPCResult::Type::ARR, "relevant_blocks", "Blocks that may have matched a scanobject.", {
                     {RPCResult::Type::STR_HEX, "blockhash", "A relevant blockhash"},
                 }},
+                {RPCResult::Type::BOOL, "completed", "true if the scan process was not aborted"}
             }},
             RPCResult{"when action=='status' and a scan is currently in progress", RPCResult::Type::OBJ, "", "", {
                     {RPCResult::Type::NUM, "progress", "Approximate percent complete"},
@@ -2358,8 +2359,7 @@ static RPCHelpMan scanblocks()
         // set the abort flag
         g_scanfilter_should_abort_scan = true;
         return true;
-    }
-    else if (request.params[0].get_str() == "start") {
+    } else if (request.params[0].get_str() == "start") {
         BlockFiltersScanReserver reserver;
         if (!reserver.reserve()) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Scan already in progress, use action \"abort\" or \"status\"");
@@ -2424,12 +2424,13 @@ static RPCHelpMan scanblocks()
         g_scanfilter_should_abort_scan = false;
         g_scanfilter_progress = 0;
         g_scanfilter_progress_height = start_block_height;
+        bool completed = true;
 
         const CBlockIndex* end_range = nullptr;
         do {
             node.rpc_interruption_point(); // allow a clean shutdown
             if (g_scanfilter_should_abort_scan) {
-                LogPrintf("scanblocks RPC aborted at height %d.\n", end_range->nHeight);
+                completed = false;
                 break;
             }
 
@@ -2453,7 +2454,6 @@ static RPCHelpMan scanblocks()
                         }
 
                         blocks.push_back(filter.GetBlockHash().GetHex());
-                        LogPrint(BCLog::RPC, "scanblocks: found match in %s\n", filter.GetBlockHash().GetHex());
                     }
                 }
             }
@@ -2472,8 +2472,9 @@ static RPCHelpMan scanblocks()
         } while (start_index != stop_block);
 
         ret.pushKV("from_height", start_block_height);
-        ret.pushKV("to_height", stop_block->nHeight);
+        ret.pushKV("to_height", start_index->nHeight); // start_index is always the last scanned block here
         ret.pushKV("relevant_blocks", blocks);
+        ret.pushKV("completed", completed);
     }
     else {
         throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid action '%s'", request.params[0].get_str()));

test/functional/rpc_scanblocks.py

@@ -48,6 +48,7 @@ def run_test(self):
         assert blockhash in out['relevant_blocks']
         assert_equal(height, out['to_height'])
         assert_equal(0, out['from_height'])
+        assert_equal(True, out['completed'])
 
         # mine another block
         blockhash_new = self.generate(node, 1)[0]