feat: New ETL by default (#2752)

src/etl/LoadBalancer.cpp

@@ -21,9 +21,10 @@
 
 #include "data/BackendInterface.hpp"
 #include "etl/ETLState.hpp"
+#include "etl/InitialLoadObserverInterface.hpp"
+#include "etl/LoadBalancerInterface.hpp"
 #include "etl/NetworkValidatedLedgersInterface.hpp"
 #include "etl/Source.hpp"
-#include "etlng/LoadBalancerInterface.hpp"
 #include "feed/SubscriptionManagerInterface.hpp"
 #include "rpc/Errors.hpp"
 #include "util/Assert.hpp"
@@ -64,7 +65,7 @@ using util::prometheus::Labels;
 
 namespace etl {
 
-std::shared_ptr<etlng::LoadBalancerInterface>
+std::shared_ptr<LoadBalancerInterface>
 LoadBalancer::makeLoadBalancer(
     ClioConfigDefinition const& config,
     boost::asio::io_context& ioc,
@@ -158,7 +159,6 @@ LoadBalancer::LoadBalancer(
         auto source = sourceFactory(
             *it,
             ioc,
-            backend,
             subscriptions,
             validatedLedgers,
             forwardingTimeout,
@@ -212,26 +212,32 @@ LoadBalancer::LoadBalancer(
     }
 }
 
-std::vector<std::string>
-LoadBalancer::loadInitialLedger(uint32_t sequence, std::chrono::steady_clock::duration retryAfter)
+InitialLedgerLoadResult
+LoadBalancer::loadInitialLedger(
+    uint32_t sequence,
+    InitialLoadObserverInterface& loadObserver,
+    std::chrono::steady_clock::duration retryAfter
+)
 {
-    std::vector<std::string> response;
-    execute(
-        [this, &response, &sequence](auto& source) {
-            auto [data, res] = source->loadInitialLedger(sequence, downloadRanges_);
+    InitialLedgerLoadResult response;
 
-            if (!res) {
+    execute(
+        [this, &response, &sequence, &loadObserver](auto& source) {
+            auto res = source->loadInitialLedger(sequence, downloadRanges_, loadObserver);
+
+            if (not res.has_value() and res.error() == InitialLedgerLoadError::Errored) {
                 LOG(log_.error()) << "Failed to download initial ledger."
                                   << " Sequence = " << sequence << " source = " << source->toString();
-            } else {
-                response = std::move(data);
+                return false;  // should retry on error
             }
 
-            return res;
+            response = std::move(res);  // cancelled or data received
+            return true;
         },
         sequence,
         retryAfter
     );
+
     return response;
 }