opentelemetry-instrumentation-system-metrics: fix typo in metrics configs

With default config it behaves correctly, with custom config changing
dropped packets affected two other measures.

Author: xrmx

instrumentation/opentelemetry-instrumentation-system-metrics/src/opentelemetry/instrumentation/system_metrics/__init__.py

@@ -595,7 +595,7 @@ def _get_system_network_packets(
         """Observer callback for network packets"""
 
         for device, counters in psutil.net_io_counters(pernic=True).items():
-            for metric in self._config["system.network.dropped.packets"]:
+            for metric in self._config["system.network.packets"]:
                 recv_sent = {"receive": "recv", "transmit": "sent"}[metric]
                 if hasattr(counters, f"packets_{recv_sent}"):
                     self._system_network_packets_labels["device"] = device
@@ -626,7 +626,7 @@ def _get_system_network_io(
         """Observer callback for network IO"""
 
         for device, counters in psutil.net_io_counters(pernic=True).items():
-            for metric in self._config["system.network.dropped.packets"]:
+            for metric in self._config["system.network.io"]:
                 recv_sent = {"receive": "recv", "transmit": "sent"}[metric]
                 if hasattr(counters, f"bytes_{recv_sent}"):
                     self._system_network_io_labels["device"] = device

instrumentation/opentelemetry-instrumentation-system-metrics/tests/test_system_metrics.py

@@ -20,6 +20,7 @@
 from unittest import mock, skipIf
 
 from opentelemetry.instrumentation.system_metrics import (
+    _DEFAULT_CONFIG,
     SystemMetricsInstrumentor,
 )
 from opentelemetry.sdk.metrics import MeterProvider
@@ -865,3 +866,13 @@ def test_open_file_descriptor_count(self, mock_process_num_fds):
             expected,
         )
         mock_process_num_fds.assert_called()
+
+
+class TestConfigSystemMetrics(TestBase):
+    def test_that_correct_config_is_read(self):
+        for k, v in _DEFAULT_CONFIG.items():
+            meter_provider = MeterProvider([InMemoryMetricReader()])
+            instrumentor = SystemMetricsInstrumentor(config={k: v})
+            instrumentor.instrument(meter_provider=meter_provider)
+            meter_provider.force_flush()
+            instrumentor.uninstrument()