Add test coverage for extract_timestamps_json_rpc_lazy

eth_defi/event_reader/lazy_timestamp_reader.py

@@ -47,6 +47,9 @@ def __init__(self, web3: Web3, start_block: int, end_block: int):
         self.cache_by_block_hash = {}
         self.cache_by_block_number = {}
 
+        #: How many API requets we have made
+        self.api_call_counter = 0
+
     def update_block_hash(self, block_identifier: BlockIdentifier) -> int:
         """Internal function to get block timestamp from JSON-RPC and store it in the cache."""
         # Skip web3.py stack of slow result formatters
@@ -56,7 +59,7 @@ def update_block_hash(self, block_identifier: BlockIdentifier) -> int:
 
         if type(block_identifier) == int:
             assert block_identifier > 0
-            result = self.web3.manager.request_blocking("eth_getBlockByNumber", (block_identifier, False))
+            result = self.web3.manager.request_blocking("eth_getBlockByNumber", (hex(block_identifier), False))
         else:
             if isinstance(block_identifier, HexBytes):
                 block_identifier = block_identifier.hex()
@@ -67,6 +70,8 @@ def update_block_hash(self, block_identifier: BlockIdentifier) -> int:
 
             result = self.web3.manager.request_blocking("eth_getBlockByHash", (block_identifier, False))
 
+        self.api_call_counter += 1
+
         # Note to self: block_number = 0 for the genesis block on Anvil
         block_number = convert_jsonrpc_value_to_int(result["number"])
         hash = result["hash"]

tests/test_event_reader.py

@@ -8,6 +8,7 @@
 
 from eth_defi.abi import get_contract
 from eth_defi.chain import install_chain_middleware
+from eth_defi.event_reader.lazy_timestamp_reader import extract_timestamps_json_rpc_lazy, LazyTimestampContainer
 from eth_defi.event_reader.reader import read_events, BadTimestampValueReturned, TimestampNotFound, read_events_concurrent
 from eth_defi.event_reader.web3factory import TunedWeb3Factory
 from eth_defi.event_reader.web3worker import create_thread_pool_executor
@@ -154,3 +155,44 @@ def test_read_events_concurrent_two_blocks_concurrent(web3):
     assert len(blocks) == 3
     assert min(blocks) == 37898275
     assert max(blocks) == 37898276
+
+
+
+def test_read_events_lazy_timestamp(web3):
+    """Read events but extract timestamps only for events, not whole block ranges.
+
+    """
+
+    # Get contracts
+    Pair = get_contract(web3, "sushi/UniswapV2Pair.json")
+
+    events = [
+        Pair.events.Swap,
+    ]
+
+    start_block = 37898275
+    end_block = start_block + 100
+    lazy_timestamp_container: LazyTimestampContainer = None
+
+    def wrapper(web3, start_block, end_block):
+        nonlocal lazy_timestamp_container
+        lazy_timestamp_container = extract_timestamps_json_rpc_lazy(web3, start_block, end_block)
+        return lazy_timestamp_container
+
+    swaps = list(
+        read_events(
+            web3,
+            start_block,
+            end_block,
+            events,
+            chunk_size=1000,
+            extract_timestamps=wrapper,
+        )
+    )
+
+    # API calls are less often than blocks we read
+    assert lazy_timestamp_container.api_call_counter == 80
+    assert len(swaps) == 206
+
+    for s in swaps:
+        assert s["timestamp"] > 0