Pay per-block price instead of per-peer price

dagger/bitswap/engine.nim

@@ -194,11 +194,8 @@ proc payForBlocks(engine: BitswapEngine,
   if sendPayment.isNil:
     return
 
-  var amountOfBytes = 0
+  let cids = blocks.mapIt(it.cid)
-  for blck in blocks:
+  if payment =? engine.wallet.pay(peer, peer.price(cids)):
-    amountOfBytes += blck.data.len
-
-  if payment =? engine.wallet.pay(peer, amountOfBytes):
     sendPayment(peer.id, payment)
 
 proc blocksHandler*(

dagger/bitswap/engine/payments.nim

@@ -30,9 +30,8 @@ func getOrOpenChannel(wallet: WalletRef, peer: BitswapPeerCtx): ?!ChannelId =
 
 func pay*(wallet: WalletRef,
           peer: BitswapPeerCtx,
-          amountOfBytes: int): ?!SignedState =
+          amount: UInt256): ?!SignedState =
   if pricing =? peer.pricing:
-    let amount = amountOfBytes.u256 * pricing.price
     let asset = Asset
     let receiver = pricing.address
     let channel = ?wallet.getOrOpenChannel(peer)

dagger/bitswap/peercontext.nim

@@ -46,3 +46,8 @@ func updatePresence*(context: BitswapPeerCtx, presence: Presence) =
   elif cid in context.peerHave and not presence.have:
     context.peerHave.keepItIf(it != cid)
     context.peerPrices.del(cid)
+
+func price*(context: BitswapPeerCtx, cids: seq[Cid]): UInt256 =
+  for cid in cids:
+    if price =? context.peerPrices.?[cid]:
+      result += price

tests/dagger/bitswap/engine/testpayments.nim

@@ -4,7 +4,7 @@ import ../../examples
 
 suite "engine payments":
 
-  let amountOfBytes = 42
+  let amount = 42.u256
 
   var wallet: WalletRef
   var peer: BitswapPeerCtx
@@ -14,19 +14,19 @@ suite "engine payments":
     peer = BitswapPeerCtx.example
     peer.pricing = Pricing.example.some
 
-  test "pays for received bytes":
+  test "pays for received blocks":
-    let payment = !wallet.pay(peer, amountOfBytes)
+    let payment = !wallet.pay(peer, amount)
     let pricing = !peer.pricing
     let balances = payment.state.outcome.balances(Asset)
     let destination = pricing.address.toDestination
-    check !balances[destination] == amountOfBytes.u256 * pricing.price
+    check !balances[destination] == amount
 
   test "no payment when no price is set":
     peer.pricing = Pricing.none
-    check wallet.pay(peer, amountOfBytes).isFailure
+    check wallet.pay(peer, amount).isFailure
 
   test "uses same channel for consecutive payments":
-    let payment1, payment2 = wallet.pay(peer, amountOfBytes)
+    let payment1, payment2 = wallet.pay(peer, amount)
     let channel1 = payment1.?state.?channel.?getChannelId
     let channel2 = payment2.?state.?channel.?getChannelId
     check channel1 == channel2

tests/dagger/bitswap/testengine.nim

@@ -1,4 +1,5 @@
 import std/sequtils
+import std/random
 
 import pkg/stew/byteutils
 import pkg/asynctest
@@ -153,10 +154,12 @@ suite "Bitswap engine handlers":
 
   test "sends payments for received blocks":
     let pricing = Pricing.example
-    engine.getPeerCtx(peerId).pricing = pricing.some
+    let peerContext = engine.getPeerCtx(peerId)
+    peerContext.pricing = pricing.some
+    peerContext.peerPrices = blocks.mapIt((it.cid, rand(uint16).u256)).toTable
 
     engine.request.sendPayment = proc(receiver: PeerID, payment: SignedState) =
-      let amount = blocks.mapIt(it.data.len).foldl(a+b).u256 * pricing.price
+      let amount = blocks.mapIt(peerContext.peerPrices[it.cid]).foldl(a+b)
       let balances = !payment.state.outcome.balances(Asset)
       check receiver == peerId
       check balances[pricing.address.toDestination] == amount

tests/dagger/examples.nim

@@ -37,7 +37,7 @@ proc example*(_: type SignedState): SignedState =
 proc example*(_: type Pricing): Pricing =
   Pricing(
     address: EthAddress.example,
-    price: uint32.example.u256
+    price: uint32.rand.u256
   )
 
 proc example*(_: type Block): Block =