rpc: call IsInitialBlockDownload via miner interface

src/interfaces/mining.h

@@ -30,6 +30,9 @@ class Mining
     //! If this chain is exclusively used for testing
     virtual bool isTestChain() = 0;
 
+    //! Returns whether IBD is still in progress.
+    virtual bool isInitialBlockDownload() = 0;
+
     //! Returns the hash for the tip of this chain
     virtual std::optional<uint256> getTipHash() = 0;
 

src/node/interfaces.cpp

@@ -847,6 +847,11 @@ class MinerImpl : public Mining
         return chainman().GetParams().IsTestChain();
     }
 
+    bool isInitialBlockDownload() override
+    {
+        return chainman().IsInitialBlockDownload();
+    }
+
     std::optional<uint256> getTipHash() override
     {
         LOCK(::cs_main);

src/rpc/mining.cpp

@@ -735,7 +735,7 @@ static RPCHelpMan getblocktemplate()
             throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, PACKAGE_NAME " is not connected!");
         }
 
-        if (chainman.IsInitialBlockDownload()) {
+        if (miner.isInitialBlockDownload()) {
             throw JSONRPCError(RPC_CLIENT_IN_INITIAL_DOWNLOAD, PACKAGE_NAME " is in initial sync and waiting for blocks...");
         }
     }