example_test.py
1 #!/usr/bin/env python3 2 # Copyright (c) 2017-present The Bitcoin Core developers 3 # Distributed under the MIT software license, see the accompanying 4 # file COPYING or http://www.opensource.org/licenses/mit-license.php. 5 """An example functional test 6 7 The module-level docstring should include a high-level description of 8 what the test is doing. It's the first thing people see when they open 9 the file and should give the reader information about *what* the test 10 is testing and *how* it's being tested 11 """ 12 # Imports should be in PEP8 ordering (std library first, then third party 13 # libraries then local imports). 14 from collections import defaultdict 15 16 # Avoid wildcard * imports 17 # Use lexicographically sorted multi-line imports 18 from test_framework.blocktools import ( 19 create_block, 20 ) 21 from test_framework.messages import ( 22 CInv, 23 MSG_BLOCK, 24 ) 25 from test_framework.p2p import ( 26 P2PInterface, 27 msg_block, 28 msg_getdata, 29 p2p_lock, 30 ) 31 from test_framework.test_framework import BitcoinTestFramework 32 from test_framework.util import ( 33 assert_equal, 34 ) 35 36 # P2PInterface is a class containing callbacks to be executed when a P2P 37 # message is received from the node-under-test. Subclass P2PInterface and 38 # override the on_*() methods if you need custom behaviour. 39 class BaseNode(P2PInterface): 40 def __init__(self): 41 """Initialize the P2PInterface 42 43 Used to initialize custom properties for the Node that aren't 44 included by default in the base class. Be aware that the P2PInterface 45 base class already stores a counter for each P2P message type and the 46 last received message of each type, which should be sufficient for the 47 needs of most tests. 48 49 Call super().__init__() first for standard initialization and then 50 initialize custom properties.""" 51 super().__init__() 52 # Stores a dictionary of all blocks received 53 self.block_receive_map = defaultdict(int) 54 55 def on_block(self, message): 56 """Override the standard on_block callback 57 58 Store the hash of a received block in the dictionary.""" 59 self.block_receive_map[message.block.hash_int] += 1 60 61 def on_inv(self, message): 62 """Override the standard on_inv callback""" 63 pass 64 65 def custom_function(): 66 """Do some custom behaviour 67 68 If this function is more generally useful for other tests, consider 69 moving it to a module in test_framework.""" 70 # self.log.info("running custom_function") # Oops! Can't run self.log outside the BitcoinTestFramework 71 pass 72 73 74 class ExampleTest(BitcoinTestFramework): 75 # Each functional test is a subclass of the BitcoinTestFramework class. 76 77 # Override the set_test_params(), skip_test_if_missing_module(), add_options(), setup_chain(), setup_network() 78 # and setup_nodes() methods to customize the test setup as required. 79 80 def set_test_params(self): 81 """Override test parameters for your individual test. 82 83 This method must be overridden and num_nodes must be explicitly set.""" 84 # By default every test loads a pre-mined chain of 200 blocks from cache. 85 # Set setup_clean_chain to True to skip this and start from the Genesis 86 # block. 87 self.setup_clean_chain = True 88 self.num_nodes = 3 89 # Use self.extra_args to change command-line arguments for the nodes 90 self.extra_args = [[], ["-logips"], []] 91 92 # self.log.info("I've finished set_test_params") # Oops! Can't run self.log before run_test() 93 94 # Use skip_test_if_missing_module() to skip the test if your test requires certain modules to be present. 95 # This test uses generate which requires wallet to be compiled 96 def skip_test_if_missing_module(self): 97 self.skip_if_no_wallet() 98 99 # Use add_options() to add specific command-line options for your test. 100 # In practice this is not used very much, since the tests are mostly written 101 # to be run in automated environments without command-line options. 102 # def add_options() 103 # pass 104 105 # Use setup_chain() to customize the node data directories. In practice 106 # this is not used very much since the default behaviour is almost always 107 # fine 108 # def setup_chain(): 109 # pass 110 111 def setup_network(self): 112 """Setup the test network topology 113 114 Often you won't need to override this, since the standard network topology 115 (linear: node0 <-> node1 <-> node2 <-> ...) is fine for most tests. 116 117 If you do override this method, remember to start the nodes, assign 118 them to self.nodes, connect them and then sync.""" 119 120 self.setup_nodes() 121 122 # In this test, we're not connecting node2 to node0 or node1. Calls to 123 # sync_all() should not include node2, since we're not expecting it to 124 # sync. 125 self.connect_nodes(0, 1) 126 self.sync_all(self.nodes[0:2]) 127 128 # Use setup_nodes() to customize the node start behaviour (for example if 129 # you don't want to start all nodes at the start of the test). 130 # def setup_nodes(): 131 # pass 132 133 def custom_method(self): 134 """Do some custom behaviour for this test 135 136 Define it in a method here because you're going to use it repeatedly. 137 If you think it's useful in general, consider moving it to the base 138 BitcoinTestFramework class so other tests can use it.""" 139 140 self.log.info("Running custom_method") 141 142 def run_test(self): 143 """Main test logic""" 144 145 # Create P2P connections will wait for a verack to make sure the connection is fully up 146 peer_messaging = self.nodes[0].add_p2p_connection(BaseNode()) 147 148 # Generating a block on one of the nodes will get us out of IBD 149 blocks = [int(self.generate(self.nodes[0], sync_fun=lambda: self.sync_all(self.nodes[0:2]), nblocks=1)[0], 16)] 150 151 # Notice above how we called an RPC by calling a method with the same 152 # name on the node object. Notice also how we used a keyword argument 153 # to specify a named RPC argument. Neither of those are defined on the 154 # node object. Instead there's some __getattr__() magic going on under 155 # the covers to dispatch unrecognised attribute calls to the RPC 156 # interface. 157 158 # Logs are nice. Do plenty of them. They can be used in place of comments for 159 # breaking the test into sub-sections. 160 self.log.info("Starting test!") 161 162 self.log.info("Calling a custom function") 163 custom_function() 164 165 self.log.info("Calling a custom method") 166 self.custom_method() 167 168 self.log.info("Create some blocks") 169 self.tip = int(self.nodes[0].getbestblockhash(), 16) 170 self.block_time = self.nodes[0].getblock(self.nodes[0].getbestblockhash())['time'] + 1 171 172 height = self.nodes[0].getblockcount() 173 174 for _ in range(10): 175 # Use the blocktools functionality to manually build a block. 176 # Calling the generate() rpc is easier, but this allows us to exactly 177 # control the blocks and transactions. 178 block = create_block(self.tip, height=height+1, ntime=self.block_time) 179 block.solve() 180 block_message = msg_block(block) 181 # Send message is used to send a P2P message to the node over our P2PInterface 182 peer_messaging.send_without_ping(block_message) 183 self.tip = block.hash_int 184 blocks.append(self.tip) 185 self.block_time += 1 186 height += 1 187 188 self.log.info("Wait for node1 to reach current tip (height 11) using RPC") 189 self.nodes[1].waitforblockheight(11) 190 191 self.log.info("Connect node2 and node1") 192 self.connect_nodes(1, 2) 193 194 self.log.info("Wait for node2 to receive all the blocks from node1") 195 self.sync_all() 196 197 self.log.info("Add P2P connection to node2") 198 self.nodes[0].disconnect_p2ps() 199 200 peer_receiving = self.nodes[2].add_p2p_connection(BaseNode()) 201 202 self.log.info("Test that node2 propagates all the blocks to us") 203 204 getdata_request = msg_getdata() 205 for block in blocks: 206 getdata_request.inv.append(CInv(MSG_BLOCK, block)) 207 peer_receiving.send_without_ping(getdata_request) 208 209 # wait_until() will loop until a predicate condition is met. Use it to test properties of the 210 # P2PInterface objects. 211 peer_receiving.wait_until(lambda: sorted(blocks) == sorted(list(peer_receiving.block_receive_map.keys())), timeout=5) 212 213 self.log.info("Check that each block was received only once") 214 # The network thread uses a global lock on data access to the P2PConnection objects when sending and receiving 215 # messages. The test thread should acquire the global lock before accessing any P2PConnection data to avoid locking 216 # and synchronization issues. Note p2p.wait_until() acquires this global lock internally when testing the predicate. 217 with p2p_lock: 218 for block in peer_receiving.block_receive_map.values(): 219 assert_equal(block, 1) 220 221 222 if __name__ == '__main__': 223 ExampleTest(__file__).main()