Merge pull request ethereum#10 from ethers/tidy

separate out incentives; update README with live testnet info

Author: ethers

README.md

@@ -1,15 +1,15 @@
-# btcrelay
+# [BTC Relay](http://btcrelay.org)
 
-[![Join the chat at https://gitter.im/ethereum/btcrelay](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ethereum/btcrelay?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+[![Join the chat at https://gitter.im/ethereum/btcrelay](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/ethereum/btcrelay)
 
-btcrelay is an Ethereum contract for Bitcoin SPV.  The main functionality it provides are:
+[BTC Relay](http://btcrelay.org) is an Ethereum contract for Bitcoin SPV.  The main functionality it provides are:
 
 1. verification of a Bitcoin transaction
 1. optionally relay the Bitcoin transaction to any Ethereum contract
 1. storage of Bitcoin block headers
 1. inspection of the latest Bitcoin block header that is stored
 
-btcrelay is on the Olympic testnet.  Use `web3.eth.namereg.addr('btcrelay')` or run Ethereum JSON-RPC (default port 8545) and click [here](http://cdn.rawgit.com/ethereum/btcrelay/master/examples/relayContractStatus.html)
+BTC Relay is [live](http://rawgit.com/ethereum/btcrelay/master/examples/relayContractStatus.html) on the testnet.
 
 
 ## API

btcrelay.se

@@ -1,4 +1,5 @@
 inset('btcChain.se')
+inset('incentive.se')
 
 # btcrelay can relay a transaction to any contract that has a function
 # name 'processTransaction' with signature bytes,uint256:int256
@@ -17,6 +18,7 @@ extern relayDestination: [processTransaction:[bytes,uint256]:int256]
 # -   "_ibIndex" is the block's index to internalBlock (see btcChain)
 # -   "_score" is 1 more than the cumulative difficulty [see setInitialParent()]
 # - _ancestor stores 8 32bit ancestor indices for more efficient backtracking (see btcChain)
+# - _feeInfo is used for incentive.se (see m_getFeeInfo)
 data block[2**256](_info, _ancestor, _blockHeader[], _feeInfo)
 
 
@@ -27,9 +29,9 @@ data heaviestBlock
 data highScore
 
 event Failure(errCode:indexed)
-event EthPayment()
 
 def init():
+    # gasPriceAndChangeRecipientFee in incentive.se
     self.gasPriceAndChangeRecipientFee = 50 * 10**9 * BYTES_16 # 50 shannon and left-align
     # TODO anything else to init ?
     # carefully test if adding anything to init() since
@@ -150,84 +152,6 @@ def storeBlockHeader(blockHeaderBytes:str):
 
     return(0)
 
-# 16 bytes last gas price and 16 bytes of change recipient fee
-data gasPriceAndChangeRecipientFee
-
-macro m_getLastGasPrice():
-    div(self.gasPriceAndChangeRecipientFee, BYTES_16)
-
-macro m_getChangeRecipientFee():
-    (0x00000000000000000000000000000000ffffffffffffffffffffffffffffffff & self.gasPriceAndChangeRecipientFee)
-
-macro m_setGasPriceAndChangeRecipientFee($gasPrice, $changeRecipientFee):
-    self.gasPriceAndChangeRecipientFee = ($gasPrice * BYTES_16) | $changeRecipientFee
-
-def storeBlockWithFee(blockHeaderBytes:str, feeWei):
-    beginGas = msg.gas
-    res = self.storeBlockHeader(blockHeaderBytes)
-    if res:
-        blockHash = m_hashBlockHeader(blockHeaderBytes)
-        m_setFeeInfo(blockHash, feeWei, tx.origin)  # note: tx.origin
-        remainingGas = msg.gas
-
-
-        gLastGasPrice = m_getLastGasPrice()
-
-        # TODO can avoid the "else"
-        if tx.gasprice < (1023*gLastGasPrice/1024) || tx.gasprice > (1025*gLastGasPrice/1024):
-            currGP = gLastGasPrice
-        else:
-            currGP = tx.gasprice
-        gChangeRecipientFee = 2 * currGP * (beginGas - remainingGas)
-        gLastGasPrice = currGP
-
-        m_setGasPriceAndChangeRecipientFee(gLastGasPrice, gChangeRecipientFee)
-
-        return(res)
-
-
-macro m_setFeeInfo($blockHash, $feeWei, $feeRecipient):
-    $word = m_shiftLeft($feeRecipient, 12*8) | $feeWei
-    self.block[$blockHash]._feeInfo = $word
-
-
-macro m_getFeeInfo($blockHash):
-    self.block[$blockHash]._feeInfo
-
-def getFee(blockHash):
-    # TODO macro
-    return(0x0000000000000000000000000000000000000000ffffffffffffffffffffffff & m_getFeeInfo(blockHash))
-
-def getFeeRecipient(blockHash):
-    return(div(m_getFeeInfo(blockHash), 2**(12*8)))
-
-# TODO callers must send EXACTLY the block's current fee
-# There are 2 types of amountWei: the "verifyTxFee" and "changeRecipientFee"
-# This does NOT return any funds to incorrect callers
-def feePaid(txBlockHash, amountWei):
-    feeInfo = m_getFeeInfo(txBlockHash)
-    feeRecipient = div(feeInfo, 2**(12*8))
-    # TODO allow overpayment?
-    if msg.value == amountWei:  # must not allow overpayment, otherwise fees could be increased via changeFeeRecipient()
-        send(feeRecipient, msg.value)
-        return(1)
-    return(0)
-
-
-# callers must send EXACTLY the block's current fee, AND feeWei must be LESS
-# than the block's current fee
-# This does NOT return any funds to incorrect callers
-def changeFeeRecipient(blockHash, feeWei, feeRecipient):
-    if !self.feePaid(blockHash, m_getChangeRecipientFee(), value=msg.value):
-        return(0)
-
-    # feeWei is only allowed to decrease
-    if feeWei < self.getFee(blockHash):  # TODO macro
-        m_setFeeInfo(blockHash, feeWei, feeRecipient)
-        return(1)
-
-    return(0)
-
 
 # returns 1 if tx is in the block given by 'txBlockHash' and the block is
 # in Bitcoin's main chain (ie not a fork)
@@ -237,12 +161,9 @@ def changeFeeRecipient(blockHash, feeWei, feeRecipient):
 # - 'txIndex' is the index of the tx within the block
 # - 'sibling' are the merkle siblings of tx
 def verifyTx(txHash, txIndex, sibling:arr, txBlockHash):
-    ethFee = self.getFee(txBlockHash)
-    if !self.feePaid(txBlockHash, ethFee, value=msg.value):
+    if !self.feePaid(txBlockHash, m_getFeeAmount(txBlockHash), value=msg.value):  # in incentive.se
         return(0)
 
-    log(type=EthPayment)
-
     if self.within6Confirms(txBlockHash) || !self.inMainChain(txBlockHash):
         return(0)
 

incentive.se

@@ -0,0 +1,107 @@
+# Incentive for block header relayers is they can set a fee for use of
+# the header they store: they are the initial feeRecipient.
+# By paying a changeRecipientFee to feeRecipient, anyone can lower the fee and
+# become the feeRecipient: this is a mechanism to prevent excessive fees.
+#
+# Tested by test/test_fee.py
+
+# first 16 bytes are the last gas price; last 16 bytes is the changeRecipientFee
+data gasPriceAndChangeRecipientFee
+
+event EthPayment(recipient:indexed, amount)
+
+
+# sets _feeInfo for the block and updates gasPriceAndChangeRecipientFee
+def storeBlockWithFee(blockHeaderBytes:str, feeWei):
+    beginGas = msg.gas
+    res = self.storeBlockHeader(blockHeaderBytes)
+    if res:
+        blockHash = m_hashBlockHeader(blockHeaderBytes)
+        m_setFeeInfo(blockHash, feeWei, tx.origin)  # note: tx.origin
+        remainingGas = msg.gas
+
+
+        gLastGasPrice = m_getLastGasPrice()
+
+        # TODO can avoid the "else"
+        if tx.gasprice < (1023*gLastGasPrice/1024) || tx.gasprice > (1025*gLastGasPrice/1024):
+            currGP = gLastGasPrice
+        else:
+            currGP = tx.gasprice
+        gChangeRecipientFee = 2 * currGP * (beginGas - remainingGas)
+        gLastGasPrice = currGP
+
+        m_setGasPriceAndChangeRecipientFee(gLastGasPrice, gChangeRecipientFee)
+
+        return(res)
+
+
+# if the EXACT fee for given txBlockHash is provided, pay the feeRecipient
+# and return 1.  otherwise return 0.
+# This does NOT return any funds to incorrect callers
+def feePaid(txBlockHash, amountWei):
+    if msg.value == amountWei:  # does not allow overpayment
+        if msg.value > 0:
+            feeRecipient = m_getFeeRecipient(txBlockHash)
+            send(feeRecipient, msg.value)
+            log(type=EthPayment, feeRecipient, msg.value)
+        return(1)
+    return(0)
+
+
+# callers must send EXACTLY the block's current fee, AND feeWei must be LESS
+# than the block's current fee
+# This does NOT return any funds to incorrect callers
+def changeFeeRecipient(blockHash, feeWei, feeRecipient):
+    if !self.feePaid(blockHash, m_getChangeRecipientFee(), value=msg.value):
+        return(0)
+
+    # feeWei is only allowed to decrease
+    if feeWei < m_getFeeAmount(blockHash):
+        m_setFeeInfo(blockHash, feeWei, feeRecipient)
+        return(1)
+
+    return(0)
+
+
+def getFeeRecipient(blockHash):
+    return(m_getFeeRecipient(blockHash))
+
+def getFeeAmount(blockHash):
+    return(m_getFeeAmount(blockHash))
+
+def getChangeRecipientFee():
+    return(m_getChangeRecipientFee())
+
+
+#
+# macros for a block's _feeInfo
+#
+# _feeInfo has first 20 bytes as the feeRecipient and
+# the last 12 bytes is the feeAmount
+#
+macro m_getFeeInfo($blockHash):
+    self.block[$blockHash]._feeInfo
+
+macro m_setFeeInfo($blockHash, $feeWei, $feeRecipient):
+    $word = ($feeRecipient * BYTES_12) | $feeWei
+    self.block[$blockHash]._feeInfo = $word
+
+macro m_getFeeRecipient($blockHash):
+    div(m_getFeeInfo($blockHash), BYTES_12)
+
+macro m_getFeeAmount($blockHash):
+    0x0000000000000000000000000000000000000000ffffffffffffffffffffffff & m_getFeeInfo($blockHash)
+
+
+#
+# macros for gasPriceAndChangeRecipientFee
+#
+macro m_getLastGasPrice():
+    div(self.gasPriceAndChangeRecipientFee, BYTES_16)
+
+macro m_getChangeRecipientFee():
+    (0x00000000000000000000000000000000ffffffffffffffffffffffffffffffff & self.gasPriceAndChangeRecipientFee)
+
+macro m_setGasPriceAndChangeRecipientFee($gasPrice, $changeRecipientFee):
+    self.gasPriceAndChangeRecipientFee = ($gasPrice * BYTES_16) | $changeRecipientFee

test/btcrelay_fee.se

@@ -6,11 +6,6 @@ def funcGetFeeInfo(blockHash):
 def funcGetLastGasPrice():
     return(m_getLastGasPrice())
 
-def funcGetChangeRecipientFee():
-    return(m_getChangeRecipientFee())
-
-def getChangeRecipientFee():
-    return(m_getChangeRecipientFee())
 
 # TODO move this to btcBulkStoreHeaders.se and remove bulkStoreHeader()
 def bulkStoreHeaderWithFee(headersBytes:str, count, feeWei):

test/test_fee.py

@@ -16,7 +16,7 @@ class TestMacros(object):
     ETHER = 10 ** 18
 
     def setup_class(cls):
-        tester.gas_limit = int(3.5e6)  # include costs of debug methods
+        tester.gas_limit = int(3.7e6)  # include costs of debug methods
         cls.s = tester.state()
         cls.c = cls.s.abi_contract(cls.CONTRACT_DEBUG, endowment=2000*cls.ETHER)
         cls.snapshot = cls.s.snapshot()

test/test_macros.py

@@ -277,12 +277,11 @@ def testEachConfirmation(self):
             else:
                 assert 0 == res == userEthBalance
 
-                assert eventArr == [{'_event_type': 'EthPayment'},
+                assert eventArr == [
                     {'_event_type': 'Failure',
                     'errCode': self.ERR_RELAY_VERIFY
                     }]
                 eventArr.pop()
-                eventArr.pop()
 
 
     def test7BlockValidTx(self):