Add Chart JSON processing to Telemetry.

tools/telemetry/telemetry/results/chart_json.py

Index: tools/telemetry/telemetry/results/chart_json.py
diff --git a/tools/telemetry/telemetry/results/chart_json.py b/tools/telemetry/telemetry/results/chart_json.py
new file mode 100644
index 0000000000000000000000000000000000000000..68711ad8ac36d244fad278df832d37d45f19b867
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+++ b/tools/telemetry/telemetry/results/chart_json.py
@@ -0,0 +1,57 @@
+# Copyright 2014 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import collections
+import itertools
+
+from telemetry.value import summary as summary_module
+
+def ResultsAsChartDict(benchmark_metadata, page_specific_values,
+                       summary_values):
+  """Produces a dict for serialization to Chart JSON format from raw values.
+
+  Chart JSON is a transformation of the basic Telemetry JSON format that
+  removes the page map, summarizes the raw values, and organizes the results
+  by chart and trace name. This function takes the key pieces of data needed to
+  perform this transformation (namely, lists of values and a benchmark metadata
+  object) and processes them into a dict which can be serialized using the json
+  module.
+
+  Design doc for schema: http://goo.gl/kOtf1Y
+
+  Args:
+    page_specific_values: list of page-specific values
+    summary_values: list of summary values
+    benchmark_metadata: a benchmark.BenchmarkMetadata object
+
+  Returns:
+    A Chart JSON dict corresponding to the given data.
+  """
+  summary = summary_module.Summary(page_specific_values)
+  values = itertools.chain(
+      summary.interleaved_computed_per_page_values_and_summaries,
+      summary_values)
+  charts = collections.defaultdict(dict)
+
+  for value in values:
+    if value.page:
+      chart_name, trace_name = (
+          value.GetChartAndTraceNameForPerPageResult())
+    else:
+      chart_name, trace_name = (
+          value.GetChartAndTraceNameForComputedSummaryResult(None))
+      if chart_name == trace_name:
+        trace_name = 'summary'
+
+    assert trace_name not in charts[chart_name]
+
+    charts[chart_name][trace_name] = value.AsDict()
+
+  result_dict = {
+    'format_version': '0.1',
+    'benchmark_name': benchmark_metadata.name,
+    'charts': charts
+  }
+
+  return result_dict