def LoadTraces(chrome_trace_filename):
"""Load traces from a file and return them as a python list.
There are several tools in tracing/bin that deal with reading traces from a
file. None of them does exactly what we need here. In particular,
merge_traces.LoadTrace will discard all traces but one if an HTML file has
several traces.
TODO(chiniforooshan): create a module for reading/writing different trace file
formats and make every other tool use that module.
"""
traces = []
if chrome_trace_filename.endswith(GZIP_FILENAME_SUFFIX):
with gzip.open(chrome_trace_filename, 'rb') as f:
traces.append(json.load(f))
elif chrome_trace_filename.endswith(HTML_FILENAME_SUFFIX):
with codecs.open(chrome_trace_filename, mode='r',
encoding='utf-8') as f:
traces = html2trace.ReadTracesFromHTMLFile(f)
elif chrome_trace_filename.endswith(JSON_FILENAME_SUFFIX):
with open(chrome_trace_filename, 'r') as f:
traces.append(json.load(f))
else:
raise Exception('Unknown trace file suffix: %s', chrome_trace_filename)
return map(_ConvertToDictIfNecessary, traces)
def testSerialize(self):
test_dir = tempfile.mkdtemp()
trace_path = os.path.join(test_dir, 'test_trace.json')
try:
ri = trace_data.CreateTraceDataFromRawData({'traceEvents': [1, 2, 3]})
ri.Serialize(trace_path)
with open(trace_path) as f:
json_traces = html2trace.ReadTracesFromHTMLFile(f)
self.assertEqual(json_traces, [{'traceEvents': [1, 2, 3]}])
finally:
shutil.rmtree(test_dir)
def LoadHTMLTrace(filename):
"""Load a trace from a vulcanized HTML trace file."""
trace_components = collections.defaultdict(list)
with open(filename) as file_handle:
for sub_trace in html2trace.ReadTracesFromHTMLFile(file_handle):
for name, component in TraceAsDict(sub_trace).items():
trace_components[name].append(component)
trace = {}
for name, components in trace_components.items():
if len(components) == 1:
trace[name] = components[0]
elif all(isinstance(component, list) for component in components):
trace[name] = [e for component in components for e in component]
else:
trace[name] = components[0]
logging.warning(
'Values of repeated trace component %r in HTML trace %r are not '
'lists. The first defined value of the component will be used.',
filename, name)
return trace
def ExtractTracesFromFile(self, trace_file_handle):
return html2trace.ReadTracesFromHTMLFile(trace_file_handle)