Auto merge of #1602 - str4d:1424-minimal-getblocktemplate, r=daira

Minimal modifications to getblocktemplate

A simpler alternative to #1435 that ensures Zcash GBT will remain compatible with BIP 22.

Closes #1424

qa/pull-tester/rpc-tests.sh

@@ -31,6 +31,7 @@ testScripts=(
     'walletbackup.py'
     'zcjoinsplit.py'
     'zcjoinsplitdoublespend.py'
+    'getblocktemplate.py'
 );
 testScriptsExt=(
     'bipdersig-p2p.py'

qa/rpc-tests/getblocktemplate.py

@@ -0,0 +1,58 @@
+#!/usr/bin/env python2
+# Copyright (c) 2016 The Zcash developers
+# Distributed under the MIT software license, see the accompanying
+# file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
+
+
+class GetBlockTemplateTest(BitcoinTestFramework):
+    '''
+    Test getblocktemplate.
+    '''
+
+    def setup_chain(self):
+        print("Initializing test directory "+self.options.tmpdir)
+        initialize_chain_clean(self.options.tmpdir, 4)
+
+    def setup_network(self, split=False):
+        self.nodes = start_nodes(2, self.options.tmpdir)
+        connect_nodes_bi(self.nodes,0,1)
+        self.is_network_split=False
+        self.sync_all()
+
+    def run_test(self):
+        node = self.nodes[0]
+        node.generate(1) # Mine a block to leave initial block download
+
+        # Test 1: Default to coinbasetxn
+        tmpl = node.getblocktemplate()
+        assert('coinbasetxn' in tmpl)
+        assert('coinbasevalue' not in tmpl)
+
+        # Test 2: Get coinbasetxn if requested
+        tmpl = node.getblocktemplate({'capabilities': ['coinbasetxn']})
+        assert('coinbasetxn' in tmpl)
+        assert('coinbasevalue' not in tmpl)
+
+        # Test 3: coinbasevalue not supported if requested
+        tmpl = node.getblocktemplate({'capabilities': ['coinbasevalue']})
+        assert('coinbasetxn' in tmpl)
+        assert('coinbasevalue' not in tmpl)
+
+        # Test 4: coinbasevalue not supported if both requested
+        tmpl = node.getblocktemplate({'capabilities': ['coinbasetxn', 'coinbasevalue']})
+        assert('coinbasetxn' in tmpl)
+        assert('coinbasevalue' not in tmpl)
+
+        # Test 5: General checks
+        tmpl = node.getblocktemplate()
+        assert(len(tmpl['noncerange']) == 16)
+
+        # Test 6: coinbasetxn checks
+        assert('foundersreward' in tmpl['coinbasetxn'])
+        assert(tmpl['coinbasetxn']['required'])
+
+if __name__ == '__main__':
+    GetBlockTemplateTest().main()

qa/rpc-tests/getblocktemplate_proposals.py

@@ -71,9 +71,11 @@ def genmrklroot(leaflist):
 def template_to_bytes(tmpl, txlist):
     blkver = pack('<L', tmpl['version'])
     mrklroot = genmrklroot(list(dblsha(a) for a in txlist))
+    reserved = b'\0'*32
     timestamp = pack('<L', tmpl['curtime'])
-    nonce = b'\0\0\0\0'
-    blk = blkver + a2b_hex(tmpl['previousblockhash'])[::-1] + mrklroot + timestamp + a2b_hex(tmpl['bits'])[::-1] + nonce
+    nonce = b'\0'*32
+    soln = b'\0'
+    blk = blkver + a2b_hex(tmpl['previousblockhash'])[::-1] + mrklroot + reserved + timestamp + a2b_hex(tmpl['bits'])[::-1] + nonce + soln
     blk += varlenEncode(len(txlist))
     for tx in txlist:
         blk += tx