tests/regression/tools/context/test_ust.py

   1 #!/usr/bin/env python3
   2 #
   3 # Copyright (C) 2022 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   4 #
   5 # SPDX-License-Identifier: GPL-2.0-only
   6
   7 from cgi import test
   8 import pathlib
   9 import sys
  10 import os
  11 from typing import Any, Callable, Type
  12
  13 """
  14 Test the addition of various user space contexts.
  15
  16 This test successively sets up a session with a certain context enabled, traces
  17 a test application, and then reads the resulting trace to determine if:
  18   - the context field is present in the trace
  19   - the context field has the expected value.
  20
  21 The vpid, vuid, vgid and java application contexts are validated by this test.
  22 """
  23
  24 # Import in-tree test utils
  25 test_utils_import_path = pathlib.Path(__file__).absolute().parents[3] / "utils"
  26 sys.path.append(str(test_utils_import_path))
  27
  28 import lttngtest
  29 import bt2
  30
  31
  32 def context_trace_field_name(context_type: Type[lttngtest.ContextType]) -> str:
  33     if isinstance(context_type, lttngtest.VpidContextType):
  34         return "vpid"
  35     elif isinstance(context_type, lttngtest.VuidContextType):
  36         return "vuid"
  37     elif isinstance(context_type, lttngtest.VgidContextType):
  38         return "vgid"
  39     elif isinstance(context_type, lttngtest.JavaApplicationContextType):
  40         # Depends on the trace format and will need to be adapted for CTF 2.
  41         return "_app_{retriever}_{name}".format(
  42             retriever=context_type.retriever_name, name=context_type.field_name
  43         )
  44     else:
  45         raise NotImplementedError
  46
  47
  48 def trace_stream_class_has_context_field_in_event_context(
  49     trace_location: pathlib.Path, context_field_name: str
  50 ) -> bool:
  51     iterator = bt2.TraceCollectionMessageIterator(str(trace_location))
  52
  53     # A bt2 message sequence is guaranteed to begin with a StreamBeginningMessage.
  54     # Since we only have one channel (one stream class) and one trace, it is
  55     # safe to use it to determine if the stream class contains the expected
  56     # context field.
  57     stream_begin_msg = next(iterator)
  58
  59     trace_class = stream_begin_msg.stream.trace.cls
  60     # Ensure the trace class has only one stream class.
  61     assert len(trace_class)
  62
  63     stream_class_id = next(iter(trace_class))
  64     stream_class = trace_class[stream_class_id]
  65     event_common_context_field_class = stream_class.event_common_context_field_class
  66
  67     return context_field_name in event_common_context_field_class
  68
  69
  70 def trace_events_have_context_value(
  71     trace_location: pathlib.Path, context_field_name: str, value: Any
  72 ) -> bool:
  73     for msg in bt2.TraceCollectionMessageIterator(str(trace_location)):
  74         if type(msg) is not bt2._EventMessageConst:
  75             continue
  76
  77         if msg.event.common_context_field[context_field_name] != value:
  78             print(msg.event.common_context_field[context_field_name])
  79             return False
  80     return True
  81
  82
  83 def test_static_context(
  84     tap: lttngtest.TapGenerator,
  85     test_env: lttngtest._Environment,
  86     context_type: lttngtest.ContextType,
  87     context_value_retriever: Callable[[lttngtest.WaitTraceTestApplication], Any],
  88 ) -> None:
  89     tap.diagnostic(
  90         "Test presence and expected value of context `{context_name}`".format(
  91             context_name=type(context_type).__name__
  92         )
  93     )
  94
  95     session_output_location = lttngtest.LocalSessionOutputLocation(
  96         test_env.create_temporary_directory("trace")
  97     )
  98
  99     client: lttngtest.Controller = lttngtest.LTTngClient(test_env, log=tap.diagnostic)
 100
 101     with tap.case("Create a session") as test_case:
 102         session = client.create_session(output=session_output_location)
 103     tap.diagnostic("Created session `{session_name}`".format(session_name=session.name))
 104
 105     with tap.case(
 106         "Add a channel to session `{session_name}`".format(session_name=session.name)
 107     ) as test_case:
 108         channel = session.add_channel(lttngtest.TracingDomain.User)
 109     tap.diagnostic("Created channel `{channel_name}`".format(channel_name=channel.name))
 110
 111     with tap.case(
 112         "Add {context_type} context to channel `{channel_name}`".format(
 113             context_type=type(context_type).__name__, channel_name=channel.name
 114         )
 115     ) as test_case:
 116         channel.add_context(context_type)
 117
 118     test_app = test_env.launch_wait_trace_test_application(50)
 119
 120     # Only track the test application
 121     session.user_vpid_process_attribute_tracker.track(test_app.vpid)
 122     expected_context_value = context_value_retriever(test_app)
 123
 124     # Enable all user space events, the default for a user tracepoint event rule.
 125     channel.add_recording_rule(lttngtest.UserTracepointEventRule())
 126
 127     session.start()
 128     test_app.trace()
 129     test_app.wait_for_exit()
 130     session.stop()
 131     session.destroy()
 132
 133     tap.test(
 134         trace_stream_class_has_context_field_in_event_context(
 135             session_output_location.path, context_trace_field_name(context_type)
 136         ),
 137         "Stream class contains field `{context_field_name}`".format(
 138             context_field_name=context_trace_field_name(context_type)
 139         ),
 140     )
 141
 142     tap.test(
 143         trace_events_have_context_value(
 144             session_output_location.path,
 145             context_trace_field_name(context_type),
 146             expected_context_value,
 147         ),
 148         "Trace's events contain the expected `{context_field_name}` value `{expected_context_value}`".format(
 149             context_field_name=context_trace_field_name(context_type),
 150             expected_context_value=expected_context_value,
 151         ),
 152     )
 153
 154
 155 tap = lttngtest.TapGenerator(20)
 156 tap.diagnostic("Test user space context tracing")
 157
 158 with lttngtest.test_environment(with_sessiond=True, log=tap.diagnostic) as test_env:
 159     test_static_context(
 160         tap, test_env, lttngtest.VpidContextType(), lambda test_app: test_app.vpid
 161     )
 162     test_static_context(
 163         tap, test_env, lttngtest.VuidContextType(), lambda test_app: os.getuid()
 164     )
 165     test_static_context(
 166         tap, test_env, lttngtest.VgidContextType(), lambda test_app: os.getgid()
 167     )
 168     test_static_context(
 169         tap,
 170         test_env,
 171         lttngtest.JavaApplicationContextType("mayo", "ketchup"),
 172         lambda test_app: {},
 173     )
 174
 175 sys.exit(0 if tap.is_successful else 1)