Merge pull request #527 from lidofinance/increase-converage-middleware

Increase middleware coverage

src/web3py/middleware.py

@@ -31,7 +31,7 @@ def metrics_collector(
         with open(os.path.join(abi_dir, filename), 'r') as f:
             try:
                 contracts.append(w3.eth.contract(abi=json.load(f)))
-            except json.JSONDecodeError:
+            except json.JSONDecodeError:  # pragma: no cover
                 pass
 
     def middleware(method: RPCEndpoint, params: Any) -> RPCResponse:
@@ -49,7 +49,7 @@ def middleware(method: RPCEndpoint, params: Any) -> RPCResponse:
             for contract in contracts:
                 try:
                     call_method = contract.get_function_by_selector(args['data']).fn_name
-                except ValueError:
+                except ValueError:  # pragma: no cover
                     pass
                 if call_method:
                     break

tests/web3_extentions/test_middleware.py

@@ -1,7 +1,10 @@
+from unittest.mock import call, Mock, patch, mock_open, MagicMock, ANY
+
 import pytest
 from requests import HTTPError
 from web3 import Web3, HTTPProvider
 from web3.exceptions import MethodUnavailable
+from web3_multi_provider import NoActiveProviderError
 
 from src.metrics.prometheus.basic import EL_REQUESTS_DURATION
 from src.variables import EXECUTION_CLIENT_URI
@@ -35,7 +38,7 @@ def _get_requests_labels():
     return labels
 
 
-def test_success(provider, web3):
+def test_success(web3):
     web3.eth.get_block_number()
     labels = _get_requests_labels()
     assert labels == {
@@ -61,11 +64,142 @@ def test_fail_with_status_code(provider, web3):
     }
 
 
-def test_fail_with_body_error(provider, web3):
+def test_fail_with_body_error(web3):
     with pytest.raises((MethodUnavailable, ValueError)):
         web3.eth.coinbase
     labels = _get_requests_labels()
     assert labels in [
         {'call_method': '', 'call_to': '', 'code': '-32601', 'endpoint': 'eth_coinbase', 'le': '0.01'},
         {'call_method': '', 'call_to': '', 'code': '-32000', 'endpoint': 'eth_coinbase', 'le': '0.01'},
     ]
+
+
+class TestMetricsCollectorUnit:
+
+    @pytest.fixture
+    def mock_web3(self):
+        """Mock Web3 instance."""
+        mock_w3 = MagicMock(spec=Web3)
+        mock_w3.provider = MagicMock()
+        mock_w3.eth = Mock()
+        mock_w3.provider.endpoint_uri = 'http://localhost:8545'
+        return mock_w3
+
+    @pytest.fixture
+    def mock_make_request(self):
+        """Mock for make_request callable."""
+        return Mock()
+
+    @pytest.fixture
+    def mock_metrics_duration(self):
+        """Mock for EL_REQUESTS_DURATION.histogram."""
+        with patch('src.web3py.middleware.EL_REQUESTS_DURATION') as mock_histogram:
+            mock_histogram.time.return_value.__enter__ = Mock(return_value=mock_histogram)
+            mock_histogram.time.return_value.__exit__ = Mock(return_value=False)
+            yield mock_histogram
+
+    @pytest.fixture
+    def load_abi_files(self):
+        """Helper function to simulate loading ABI files from the assets directory."""
+        assets_dir = './assets/'
+        test_abi = '{"abi": [{"type": "function", "name": "testFunction", "inputs": []}]}'
+
+        with patch('os.listdir') as mock_listdir, patch('builtins.open', mock_open(read_data=test_abi)):
+            mock_listdir.return_value = ['test_contract.json']
+            yield
+
+    def test_metrics_collector_eth_call(self, mock_web3, mock_make_request, mock_metrics_duration, load_abi_files):
+        """
+        Test the metrics collector for an `eth_call` method.
+        """
+        middleware = metrics_collector(mock_make_request, mock_web3)
+
+        method = 'eth_call'
+        params = [{'to': '0x1234567890abcdef', 'data': '0xabcdef'}]
+        mock_make_request.return_value = {'result': 'success'}
+
+        response = middleware(method, params)
+
+        assert response == {'result': 'success'}
+        mock_make_request.assert_called_once_with(method, params)
+        assert mock_metrics_duration.time.called
+        assert mock_metrics_duration.labels.called
+        assert mock_metrics_duration.labels.call_args == call(
+            endpoint=method,
+            call_method=ANY,
+            call_to='0x1234567890abcdef',
+            code=0,
+            domain='localhost:8545',
+        )
+
+    def test_metrics_collector_eth_getBalance(
+        self, mock_web3, mock_make_request, mock_metrics_duration, load_abi_files
+    ):
+        """
+        Test the metrics collector for an `eth_getBalance` method.
+        """
+        middleware = metrics_collector(mock_make_request, mock_web3)
+
+        method = 'eth_getBalance'
+        params = ['0x1234567890abcdef', 'latest']
+        mock_make_request.return_value = {'result': '1000'}
+
+        response = middleware(method, params)
+
+        assert response == {'result': '1000'}
+        mock_make_request.assert_called_once_with(method, params)
+        assert mock_metrics_duration.time.called
+        assert mock_metrics_duration.labels.called
+        assert mock_metrics_duration.labels.call_args == call(
+            endpoint=method,
+            call_method=ANY,
+            call_to='0x1234567890abcdef',
+            code=0,
+            domain='localhost:8545',
+        )
+
+    def test_metrics_collector_handle_no_provider(self, mock_web3, mock_make_request, mock_metrics_duration):
+        """
+        Test that the metrics collector handles the NoActiveProviderError.
+        """
+        middleware = metrics_collector(mock_make_request, mock_web3)
+
+        method = 'eth_call'
+        params = [{'to': '0x1234567890abcdef', 'data': '0xabcdef'}]
+        mock_make_request.side_effect = NoActiveProviderError
+
+        with pytest.raises(NoActiveProviderError):
+            middleware(method, params)
+
+        assert mock_metrics_duration.labels.called
+        assert mock_metrics_duration.labels.call_args == call(
+            endpoint=method,
+            call_method=ANY,
+            call_to='0x1234567890abcdef',
+            code=None,
+            domain='localhost:8545',
+        )
+
+    def test_metrics_collector_handle_http_error(self, mock_web3, mock_make_request, mock_metrics_duration):
+        """
+        Test that the metrics collector handles HTTPError correctly.
+        """
+        middleware = metrics_collector(mock_make_request, mock_web3)
+
+        method = 'eth_call'
+        params = [{'to': '0x1234567890abcdef', 'data': '0xabcdef'}]
+        mock_response = Mock(status_code=500)
+        mock_http_error = HTTPError(response=mock_response)
+        mock_make_request.side_effect = mock_http_error
+
+        with pytest.raises(HTTPError):
+            middleware(method, params)
+
+        assert mock_metrics_duration.labels.called
+        assert mock_metrics_duration.labels.call_args == call(
+            endpoint=method,
+            call_method=ANY,
+            call_to='0x1234567890abcdef',
+            code=500,
+            domain='localhost:8545',
+        )