rhp: add RPCWriteCost

rhp/v2/rhp.go

@@ -2,10 +2,8 @@
 package rhp
 
 import (
-	"crypto/ed25519"
 	"encoding/json"
 	"fmt"
-	"math/bits"
 	"net"
 	"strings"
 	"time"
@@ -281,51 +279,67 @@ type (
 	}
 )
 
-// RPCSectorRootsCost returns the price of a SectorRoots RPC.
-func RPCSectorRootsCost(settings HostSettings, rootOffset, numRoots uint64) types.Currency {
-	proofSize := RangeProofSize(LeavesPerSector, rootOffset, rootOffset+numRoots)
-	return settings.BaseRPCPrice.
-		Add(settings.DownloadBandwidthPrice.Mul64(ed25519.SignatureSize)). // signature
-		Add(settings.DownloadBandwidthPrice.Mul64(numRoots * 32)).         // roots
-		Add(settings.DownloadBandwidthPrice.Mul64(proofSize * 32))         // proof
-}
-
 // RPCReadCost returns the price of a Read RPC.
-func RPCReadCost(settings HostSettings, sections []RPCReadRequestSection) types.Currency {
-	sectorAccessPrice := settings.SectorAccessPrice.Mul64(uint64(len(sections)))
+func RPCReadCost(settings HostSettings, sections []RPCReadRequestSection, proof bool) types.Currency {
 	var bandwidth uint64
 	for _, sec := range sections {
 		bandwidth += sec.Length
-		proofSize := RangeProofSize(LeavesPerSector, sec.Offset/LeafSize, (sec.Offset+sec.Length)/LeafSize)
-		bandwidth += proofSize * 32 // proof
+		if proof {
+			proofSize := RangeProofSize(LeavesPerSector, sec.Offset/LeafSize, (sec.Offset+sec.Length)/LeafSize)
+			bandwidth += proofSize * 32
+		}
 	}
 	if bandwidth < minMessageSize {
 		bandwidth = minMessageSize
 	}
-	bandwidthPrice := settings.DownloadBandwidthPrice.Mul64(bandwidth)
-	return settings.BaseRPCPrice.Add(sectorAccessPrice).Add(bandwidthPrice)
-}
 
-// RPCAppendCost returns the price and collateral of a Write RPC with a single
-// append operation.
-func RPCAppendCost(settings HostSettings, storageDuration, numLeaves uint64) (price, collateral types.Currency) {
-	proofSize := uint64(bits.Len64(numLeaves)) + 1 // hashes + new root
-	price = settings.BaseRPCPrice.
-		Add(settings.StoragePrice.Mul64(SectorSize).Mul64(storageDuration)).
-		Add(settings.UploadBandwidthPrice.Mul64(SectorSize)).
-		Add(settings.DownloadBandwidthPrice.Mul64(ed25519.SignatureSize)). // signature
-		Add(settings.DownloadBandwidthPrice.Mul64(proofSize * 32))         // proof
-	collateral = settings.Collateral.Mul64(SectorSize).Mul64(storageDuration)
-	// add some leeway to reduce chance of host rejecting
-	price = price.Mul64(125).Div64(100)
-	collateral = collateral.Mul64(95).Div64(100)
-	return
+	return settings.BaseRPCPrice.
+		Add(settings.SectorAccessPrice.Mul64(uint64(len(sections)))).
+		Add(settings.DownloadBandwidthPrice.Mul64(bandwidth))
 }
 
-// RPCDeleteCost returns the price of a Write RPC that deletes n sectors.
-func RPCDeleteCost(settings HostSettings, actions []RPCWriteAction, numLeaves uint64) types.Currency {
-	proofSize := DiffProofSize(actions, numLeaves) + 1 // hashes + new root
+// RPCSectorRootsCost returns the price of a SectorRoots RPC.
+func RPCSectorRootsCost(settings HostSettings, rootOffset, numRoots uint64) types.Currency {
+	proofSize := RangeProofSize(LeavesPerSector, rootOffset, rootOffset+numRoots)
 	return settings.BaseRPCPrice.
-		Add(settings.DownloadBandwidthPrice.Mul64(ed25519.SignatureSize)). // signature
-		Add(settings.DownloadBandwidthPrice.Mul64(proofSize * 32))         // proof
+		Add(settings.DownloadBandwidthPrice.Mul64(numRoots * 32)). // roots
+		Add(settings.DownloadBandwidthPrice.Mul64(proofSize * 32)) // proof
+}
+
+// RPCWriteCost returns the price and collateral of a Write RPC.
+func RPCWriteCost(settings HostSettings, actions []RPCWriteAction, numLeaves, remainingDuration uint64, proof bool) (price, collateral types.Currency) {
+	price = settings.BaseRPCPrice
+
+	var sectorsAdded, sectorsRemoved uint64
+	for _, action := range actions {
+		switch action.Type {
+		case RPCWriteActionAppend:
+			sectorsAdded++
+		case RPCWriteActionTrim:
+			sectorsRemoved -= action.A
+		case RPCWriteActionSwap:
+		default:
+			panic("unhanbled action type")
+		}
+	}
+
+	if sectorsAdded > sectorsRemoved {
+		additionalSectors := sectorsAdded - sectorsRemoved
+
+		collateral = collateral.
+			Add(settings.Collateral.Mul64(SectorSize * additionalSectors * remainingDuration)).
+			Mul64(95).Div64(100) // leeway
+
+		price = price.
+			Add(settings.StoragePrice.Mul64(SectorSize * additionalSectors * remainingDuration)).
+			Add(settings.UploadBandwidthPrice.Mul64(SectorSize * additionalSectors)).
+			Mul64(125).Div64(100) // leeway
+	}
+
+	if proof {
+		proofSize := DiffProofSize(actions, numLeaves)
+		price = price.Add(settings.DownloadBandwidthPrice.Mul64(proofSize * 32))
+	}
+
+	return
 }