Extract trace reading functions

tracetools_read/tracetools_read/__init__.py

@@ -0,0 +1,13 @@
+# Copyright 2019 Robert Bosch GmbH
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

tracetools_read/tracetools_read/utils.py

@@ -0,0 +1,101 @@
+# Copyright 2019 Robert Bosch GmbH
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Module with functions for reading traces."""
+
+from typing import Any
+from typing import Dict
+from typing import Iterable
+from typing import List
+
+import babeltrace
+
+
+DictEvent = Dict[str, Any]
+
+
+def _get_trace_ctf_events(trace_directory: str) -> Iterable[babeltrace.babeltrace.Event]:
+    """
+    Get the events of a trace.
+
+    :param trace_directory: the path to the main/top trace directory
+    :return: events iterable
+    """
+    tc = babeltrace.TraceCollection()
+    tc.add_traces_recursive(trace_directory, 'ctf')
+    return tc.events
+
+
+def get_trace_events(trace_directory: str) -> List[DictEvent]:
+    """
+    Get the events of a trace.
+
+    :param trace_directory: the path to the main/top trace directory
+    :return: events
+    """
+    return [event_to_dict(event) for event in _get_trace_ctf_events(trace_directory)]
+
+
+# List of ignored CTF fields
+_IGNORED_FIELDS = [
+    'content_size',
+    'cpu_id',
+    'events_discarded',
+    'id',
+    'packet_size',
+    'packet_seq_num',
+    'stream_id',
+    'stream_instance_id',
+    'timestamp_end',
+    'timestamp_begin',
+    'magic',
+    'uuid',
+    'v',
+]
+_DISCARD = 'events_discarded'
+
+
+def event_to_dict(event: babeltrace.babeltrace.Event) -> DictEvent:
+    """
+    Convert name, timestamp, and all other keys except those in IGNORED_FIELDS into a dictionary.
+
+    :param event: the event to convert
+    :return: the event as a dictionary
+    """
+    d = {'_name': event.name, '_timestamp': event.timestamp}
+    if hasattr(event, _DISCARD) and event[_DISCARD] > 0:
+        print(event[_DISCARD])
+    for key in [key for key in event.keys() if key not in _IGNORED_FIELDS]:
+        d[key] = event[key]
+    return d
+
+
+def get_field(event: DictEvent, field_name: str, default=None, raise_if_not_found=True) -> Any:
+    field_value = event.get(field_name, default)
+    # If enabled, raise exception as soon as possible to avoid headaches
+    if raise_if_not_found and field_value is None:
+        raise AttributeError(f'event field "{field_name}" not found!')
+    return field_value
+
+
+def get_event_name(event: DictEvent) -> str:
+    return event['_name']
+
+
+def get_event_timestamp(event: DictEvent) -> int:
+    return event['_timestamp']
+
+
+def get_procname(event: DictEvent) -> str:
+    return event['procname']