Ankr

CHANGELOG.md

@@ -1,5 +1,7 @@
 # Current
 
+- Adds support for extracting block data using Ankr
+- Adds `AnkrReorganizationMonitor`
 - Add: Aave v3 reserve data queries
 
 # 0.22.7

eth_defi/chain.py

@@ -235,3 +235,17 @@ def install_retry_middleware(web3: Web3):
     gracefully do exponential backoff retries.
     """
     web3.middleware_onion.inject(http_retry_request_with_sleep_middleware, layer=0)
+
+
+def has_ankr_support(provider: HTTPProvider) -> bool:
+    """Check if a node is an Ankr node.
+    """
+
+    assert isinstance(provider, HTTPProvider)
+
+    base_url = provider.endpoint_uri
+
+    if "https://rpc.ankr.com/" not in base_url:
+        return False
+    else:
+        return True

eth_defi/event_reader/ankr.py

@@ -0,0 +1,89 @@
+import requests
+import json
+from enum import Enum
+
+from eth_defi.event_reader.block_header import BlockHeader
+
+
+class AnkrSupportedBlockchain(Enum):
+    eth = "eth"
+    bsc = "bsc"
+    polygon = "polygon"
+    fantom = "fantom"
+    arbitrum = "arbitrum"
+    avalanche = "avalanche"
+    syscoin = "syscoin"
+
+
+def make_block_request_ankr(endpoint_url: str = "https://rpc.ankr.com/multichain/79258ce7f7ee046decc3b5292a24eb4bf7c910d7e39b691384c7ce0cfb839a01/", start_block: int | str = "latest", end_block: int | str = "latest", blockchain: AnkrSupportedBlockchain | None = None, request_id: int = 1) -> list[dict]:
+    """Fetch blocks from Ankr API
+
+    :param endpoint_url: URL of Ankr API endpoint. Should be multichain endpoint.
+
+    :param start_block: Block number to start fetching from. Can be an int or "latest".
+
+    :param end_block: Block number to end fetching at. Can be an int or "latest".
+
+    :param blockchain: Blockchain to fetch blocks from. Must be of type AnkrSupportedBlockchain.
+
+    :return: List of blocks in JSON format.
+    """
+    if start_block == "latest":
+        end_block = "latest"
+
+    assert type(start_block) == int or start_block == "latest", "start_block must be an int or 'latest'"
+    assert type(end_block) == int or end_block == "latest", "end_block must be an int or None"
+    assert isinstance(blockchain, AnkrSupportedBlockchain), "blockchain must be of type AnkrSupportedBlockchain"
+
+    headers = {
+        "accept": "application/json",
+        "content-type": "application/json",
+    }
+
+    data = {
+        "jsonrpc": "2.0",
+        "method": "ankr_getBlocks",
+        "params": {
+            "blockchain": blockchain.value,
+            "fromBlock": start_block,
+            "toBlock": end_block,
+            "includeTxs": False,
+            "includeLogs": False,
+        },
+        "id": request_id,
+    }
+
+    result = requests.post(endpoint_url, headers=headers, json=data)
+
+    j = result.json()
+
+    blocks = j["result"]["blocks"]
+
+    return blocks
+
+
+def extract_timestamps_ankr_get_block(
+    endpoint_url: str,
+    start_block: int | None = None,
+    end_block: int | None = None,
+    max_blocks_at_once: int = 30,
+) -> list[int]:
+    """Extract timestamps from Ankr API
+
+    :param endpoint_url: URL of Ankr API endpoint. Should be multichain endpoint.
+
+    :param start_block: Block number to start fetching from. Can be an int or None.
+
+    :param end_block: Block number to end fetching at. Can be an int or None.
+
+    :param max_blocks_at_once: Maximum number of blocks to fetch at once. Default is 30.
+
+    :return: List of timestamps in int format.
+    """
+    timestamps = []
+
+    for i in range(start_block, end_block + 1, max_blocks_at_once):
+        blocks = make_block_request_ankr(endpoint_url, i, min(i + max_blocks_at_once - 1, end_block))
+        timestamps.extend([int(x["timestamp"], 16) for x in blocks])
+
+    return timestamps

eth_defi/event_reader/reorganisation_monitor.py

@@ -16,10 +16,12 @@
 from tqdm import tqdm
 from web3 import Web3, HTTPProvider
 
-from eth_defi.chain import has_graphql_support
+from eth_defi.chain import has_graphql_support, has_ankr_support
 from eth_defi.event_reader.block_header import BlockHeader, Timestamp
 from eth_defi.provider.fallback import FallbackProvider
 from eth_defi.provider.mev_blocker import MEVBlockerProvider
+from eth_defi.event_reader.ankr import AnkrSupportedBlockchain, make_block_request_ankr
+
 
 logger = logging.getLogger(__name__)
 
@@ -644,6 +646,80 @@ def fetch_block_data(self, start_block, end_block) -> Iterable[BlockHeader]:
             yield BlockHeader(block_number=number, block_hash=hash, timestamp=timestamp)
 
 
+class AnkrReogranisationMonitor(ReorganisationMonitor):
+    """Watch blockchain for reorgs using eth_getBlockByNumber JSON-RPC API.
+
+    - Use expensive eth_getBlockByNumber call to download
+      block hash and timestamp from Ethereum compatible node
+    """
+
+    def __init__(self, provider: HTTPProvider, ankr_url: str | None = "https://rpc.ankr.com/multichain/79258ce7f7ee046decc3b5292a24eb4bf7c910d7e39b691384c7ce0cfb839a01/", blockchain: AnkrSupportedBlockchain | None = None, **kwargs):
+        """
+        :param provider:
+            HTTPProvider with ankr_url. Should not specify ankr_url if this is specified.
+
+        :param ankr_url:
+            Should be multichain url. Should not specify provider if this is specified.
+
+        :param blockchain:
+            Blockchain to use. AnkrSupportedBlockchain enum instance.
+        """
+
+        super().__init__(**kwargs)
+
+        assert isinstance(blockchain, AnkrSupportedBlockchain), "Must provide blockchain as AnkrSupportedBlockchain enum"
+        self.blockchain = blockchain
+
+        if provider:
+            self.ankr_url = provider.endpoint_uri
+        elif ankr_url:
+            assert not provider, "Give provider or ankr_url, not both"
+            self.ankr_url = ankr_url
+
+        # starting id for jsonrpc requests
+        self.id = 1
+
+        self.max_blocks_at_once = 30
+
+    def get_last_block_live(self) -> int:
+        """Get the chain tip (last block) using Ankr.
+
+        :return:
+            Last block number
+        """
+        return int(make_block_request_ankr(self.ankr_url, blockchain=self.blockchain)[-1]["number"], 16)
+
+    def create_block_header(self, block: dict) -> BlockHeader:
+        """Create a BlockHeader from a block dict.
+
+        :param block:
+            Block dict from Ankr.
+
+        :return:
+            BlockHeader instance
+        """
+        return BlockHeader(int(block["number"], 16), block["hash"], int(block["timestamp"], 16))
+
+    def fetch_block_data(self, start_block: int, end_block: int) -> Iterable[BlockHeader]:
+        """Fetch block headers from Ankr.
+
+        Note: can only fetch 30 blocks at a time.
+
+        :param start_block:
+            Block number to start fetching from (inclusive)
+
+        :param end_block:
+            Block number to end fetching at (inclusive)
+
+        :return:
+            Iterable of BlockHeader instances
+        """
+        blocks = make_block_request_ankr(self.ankr_url, start_block, end_block, self.blockchain, self.id)
+        self.id += 1
+        block_headers = [self.create_block_header(block) for block in blocks]
+        yield from block_headers
+
+
 class MockChainAndReorganisationMonitor(ReorganisationMonitor):
     """A dummy reorganisation monitor for unit testing.
 
@@ -738,6 +814,8 @@ def create_reorganisation_monitor(web3: Web3, check_depth=250) -> Reorganisation
         # 10x faster /graphql implementation,
         # not provided by public nodes
         reorg_mon = GraphQLReorganisationMonitor(graphql_url=urljoin(json_rpc_url, "/graphql"), check_depth=check_depth)
+    elif has_ankr_support(provider):
+        reorg_mon = AnkrReogranisationMonitor(web3, check_depth=check_depth)
     else:
         # Default slow implementation
         logger.warning("The node does not support /graphql interface. " "Downloading block headers and timestamps will be extremely slow." "Check documentation how to configure your node or choose a smaller timeframe for the buffer of trades.")

tests/test_reorganisation_monitor_ankr.py

@@ -0,0 +1,41 @@
+"""Test chain reogranisation monitor and connect to live Ankr network."""
+
+import os
+
+import pytest
+from web3 import HTTPProvider
+
+from eth_defi.chain import has_ankr_support
+from eth_defi.event_reader.reorganisation_monitor import AnkrReogranisationMonitor, AnkrSupportedBlockchain
+
+pytestmark = pytest.mark.skipif(
+    os.environ.get("JSON_RPC_ANKR_PRIVATE") is None,
+    reason="Set JSON_RPC_ANKR_PRIVATE environment variable to a privately configured Polygon node with GraphQL turned on",
+)
+
+
+def test_ankr_last_block():
+    """Get last block num using Ankr API."""
+
+    provider = HTTPProvider(os.environ["JSON_RPC_ANKR_PRIVATE"])
+    assert has_ankr_support(provider)
+
+    reorg_mon = AnkrReogranisationMonitor(provider=provider, blockchain=AnkrSupportedBlockchain.arbitrum)
+    block_number = reorg_mon.get_last_block_live()
+    assert block_number > 30_000_000
+
+
+def test_ankr_block_headers():
+    """Download block headers using Ankr API."""
+
+    provider = HTTPProvider(os.environ["JSON_RPC_ANKR_PRIVATE"])
+    assert has_ankr_support(provider)
+
+    reorg_mon = AnkrReogranisationMonitor(provider=provider, blockchain=AnkrSupportedBlockchain.arbitrum)
+
+    start_block, end_block = reorg_mon.load_initial_block_headers(block_count=5)
+
+    block = reorg_mon.get_block_by_number(start_block)
+    assert block.block_number > 0
+    assert block.block_hash.startswith("0x")
+    assert block.timestamp > 0