add support for block pruning via ABCI Commit response (#4588)

* Added BlockStore.DeleteBlock()

* Added initial block pruner prototype

* wip

* Added BlockStore.PruneBlocks()

* Added consensus setting for block pruning

* Added BlockStore base

* Error on replay if base does not have blocks

* Handle missing blocks when sending VoteSetMaj23Message

* Error message tweak

* Properly update blockstore state

* Error message fix again

* blockchain: ignore peer missing blocks

* Added FIXME

* Added test for block replay with truncated history

* Handle peer base in blockchain reactor

* Improved replay error handling

* Added tests for Store.PruneBlocks()

* Fix non-RPC handling of truncated block history

* Panic on missing block meta in needProofBlock()

* Updated changelog

* Handle truncated block history in RPC layer

* Added info about earliest block in /status RPC

* Reorder height and base in blockchain reactor messages

* Updated changelog

* Fix tests

* Appease linter

* Minor review fixes

* Non-empty BlockStores should always have base > 0

* Update code to assume base > 0 invariant

* Added blockstore tests for pruning to 0

* Make sure we don't prune below the current base

* Added BlockStore.Size()

* config: added retain_blocks recommendations

* Update v1 blockchain reactor to handle blockstore base

* Added state database pruning

* Propagate errors on missing validator sets

* Comment tweaks

* Improved error message

Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

* use ABCI field ResponseCommit.retain_height instead of retain-blocks config option

* remove State.RetainHeight, return value instead

* fix minor issues

* rename pruneHeights() to pruneBlocks()

* noop to fix GitHub borkage

Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

rpc/core/status.go

@@ -16,6 +16,20 @@ import (
 // hash, app hash, block height and time.
 // More: https://docs.tendermint.com/master/rpc/#/Info/status
 func Status(ctx *rpctypes.Context) (*ctypes.ResultStatus, error) {
+	var (
+		earliestBlockMeta     *types.BlockMeta
+		earliestBlockHash     tmbytes.HexBytes
+		earliestAppHash       tmbytes.HexBytes
+		earliestBlockTimeNano int64
+	)
+	earliestBlockHeight := blockStore.Base()
+	earliestBlockMeta = blockStore.LoadBlockMeta(earliestBlockHeight)
+	if earliestBlockMeta != nil {
+		earliestAppHash = earliestBlockMeta.Header.AppHash
+		earliestBlockHash = earliestBlockMeta.BlockID.Hash
+		earliestBlockTimeNano = earliestBlockMeta.Header.Time.UnixNano()
+	}
+
 	var latestHeight int64
 	if consensusReactor.FastSync() {
 		latestHeight = blockStore.Height()
@@ -36,8 +50,6 @@ func Status(ctx *rpctypes.Context) (*ctypes.ResultStatus, error) {
 		latestBlockTimeNano = latestBlockMeta.Header.Time.UnixNano()
 	}
 
-	latestBlockTime := time.Unix(0, latestBlockTimeNano)
-
 	var votingPower int64
 	if val := validatorAtHeight(latestHeight); val != nil {
 		votingPower = val.VotingPower
@@ -46,11 +58,15 @@ func Status(ctx *rpctypes.Context) (*ctypes.ResultStatus, error) {
 	result := &ctypes.ResultStatus{
 		NodeInfo: p2pTransport.NodeInfo().(p2p.DefaultNodeInfo),
 		SyncInfo: ctypes.SyncInfo{
-			LatestBlockHash:   latestBlockHash,
-			LatestAppHash:     latestAppHash,
-			LatestBlockHeight: latestHeight,
-			LatestBlockTime:   latestBlockTime,
-			CatchingUp:        consensusReactor.FastSync(),
+			LatestBlockHash:     latestBlockHash,
+			LatestAppHash:       latestAppHash,
+			LatestBlockHeight:   latestHeight,
+			LatestBlockTime:     time.Unix(0, latestBlockTimeNano),
+			EarliestBlockHash:   earliestBlockHash,
+			EarliestAppHash:     earliestAppHash,
+			EarliestBlockHeight: earliestBlockHeight,
+			EarliestBlockTime:   time.Unix(0, earliestBlockTimeNano),
+			CatchingUp:          consensusReactor.FastSync(),
 		},
 		ValidatorInfo: ctypes.ValidatorInfo{
 			Address:     pubKey.Address(),