use multi range requests (#800)

- Improvement: `zen builds download` now uses multi-range requests for blocks to reduce download size
- Improvement: `zen oplog-import` now uses partial block with multi-range requests for blocks to reduce download size
- Improvement: Improved feedback in log/console during `zen oplog-import`
- Improvement: `--allow-partial-block-requests` now defaults to `true` for `zen builds download` and `zen oplog-import` (was `mixed`)
- Improvement: Improved range merging analysis when downloading partial blocks

1 files changed, 4 insertions, 7 deletions

diff --git a/src/zenhttp/httpclient.cpp b/src/zenhttp/httpclient.cpp
index f94c58581..281d512cf 100644
--- a/src/zenhttp/httpclient.cpp
+++ b/src/zenhttp/httpclient.cpp
@@ -107,17 +107,14 @@ HttpClientBase::GetAccessToken()
 std::vector<std::pair<uint64_t, uint64_t>>
 HttpClient::Response::GetRanges(std::span<const std::pair<uint64_t, uint64_t>> OffsetAndLengthPairs) const
 {
-	std::vector<std::pair<uint64_t, uint64_t>> Result;
-	Result.reserve(OffsetAndLengthPairs.size());
 	if (Ranges.empty())
 	{
-		for (const std::pair<uint64_t, uint64_t>& Range : OffsetAndLengthPairs)
-		{
-			Result.emplace_back(std::make_pair(Range.first, Range.second));
-		}
-		return Result;
+		return {};
 	}
 
+	std::vector<std::pair<uint64_t, uint64_t>> Result;
+	Result.reserve(OffsetAndLengthPairs.size());
+
 	auto BoundaryIt			   = Ranges.begin();
 	auto OffsetAndLengthPairIt = OffsetAndLengthPairs.begin();
 	while (OffsetAndLengthPairIt != OffsetAndLengthPairs.end())