Merge pull request #6702 from a-veitch/add_proto

Add census protos.

7 files changed, 798 insertions, 2 deletions

diff --git a/src/core/ext/census/gen/README.md b/src/core/ext/census/gen/README.md
new file mode 100644
index 0000000000..72bef6542d
--- /dev/null
+++ b/src/core/ext/census/gen/README.md
@@ -0,0 +1,6 @@
+Files generated for use by Census stats and trace recording subsystem.
+
+#Files
+* census.pb.{h,c} - Generated from src/core/ext/census/census.proto, using the
+  script `tools/codegen/core/gen_nano_proto.sh src/proto/census/census.proto
+  $PWD/src/core/ext/census/gen src/core/ext/census/gen`
diff --git a/src/core/ext/census/gen/census.pb.c b/src/core/ext/census/gen/census.pb.c
new file mode 100644
index 0000000000..d614636c90
--- /dev/null
+++ b/src/core/ext/census/gen/census.pb.c
@@ -0,0 +1,179 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+/* Automatically generated nanopb constant definitions */
+/* Generated by nanopb-0.3.5-dev */
+
+#include "src/core/ext/census/gen/census.pb.h"
+
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+
+
+const pb_field_t google_census_Duration_fields[3] = {
+    PB_FIELD(  1, INT64   , OPTIONAL, STATIC  , FIRST, google_census_Duration, seconds, seconds, 0),
+    PB_FIELD(  2, INT32   , OPTIONAL, STATIC  , OTHER, google_census_Duration, nanos, seconds, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Timestamp_fields[3] = {
+    PB_FIELD(  1, INT64   , OPTIONAL, STATIC  , FIRST, google_census_Timestamp, seconds, seconds, 0),
+    PB_FIELD(  2, INT32   , OPTIONAL, STATIC  , OTHER, google_census_Timestamp, nanos, seconds, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Metric_fields[5] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, CALLBACK, FIRST, google_census_Metric, name, name, 0),
+    PB_FIELD(  2, STRING  , OPTIONAL, CALLBACK, OTHER, google_census_Metric, description, name, 0),
+    PB_FIELD(  3, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_Metric, unit, description, &google_census_Metric_MeasurementUnit_fields),
+    PB_FIELD(  4, INT32   , OPTIONAL, STATIC  , OTHER, google_census_Metric, id, unit, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Metric_BasicUnit_fields[2] = {
+    PB_FIELD(  1, UENUM   , OPTIONAL, STATIC  , FIRST, google_census_Metric_BasicUnit, type, type, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Metric_MeasurementUnit_fields[4] = {
+    PB_FIELD(  1, INT32   , OPTIONAL, STATIC  , FIRST, google_census_Metric_MeasurementUnit, prefix, prefix, 0),
+    PB_FIELD(  2, MESSAGE , REPEATED, CALLBACK, OTHER, google_census_Metric_MeasurementUnit, numerator, prefix, &google_census_Metric_BasicUnit_fields),
+    PB_FIELD(  3, MESSAGE , REPEATED, CALLBACK, OTHER, google_census_Metric_MeasurementUnit, denominator, numerator, &google_census_Metric_BasicUnit_fields),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_AggregationDescriptor_fields[3] = {
+    PB_ONEOF_FIELD(options,   1, MESSAGE , ONEOF, STATIC  , FIRST, google_census_AggregationDescriptor, bucket_boundaries, bucket_boundaries, &google_census_AggregationDescriptor_BucketBoundaries_fields),
+    PB_ONEOF_FIELD(options,   2, MESSAGE , ONEOF, STATIC  , FIRST, google_census_AggregationDescriptor, interval_boundaries, interval_boundaries, &google_census_AggregationDescriptor_IntervalBoundaries_fields),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_AggregationDescriptor_BucketBoundaries_fields[2] = {
+    PB_FIELD(  1, DOUBLE  , REPEATED, CALLBACK, FIRST, google_census_AggregationDescriptor_BucketBoundaries, bounds, bounds, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_AggregationDescriptor_IntervalBoundaries_fields[2] = {
+    PB_FIELD(  1, DOUBLE  , REPEATED, CALLBACK, FIRST, google_census_AggregationDescriptor_IntervalBoundaries, window_size, window_size, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Distribution_fields[5] = {
+    PB_FIELD(  1, INT64   , OPTIONAL, STATIC  , FIRST, google_census_Distribution, count, count, 0),
+    PB_FIELD(  2, DOUBLE  , OPTIONAL, STATIC  , OTHER, google_census_Distribution, mean, count, 0),
+    PB_FIELD(  3, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_Distribution, range, mean, &google_census_Distribution_Range_fields),
+    PB_FIELD(  4, INT64   , REPEATED, CALLBACK, OTHER, google_census_Distribution, bucket_count, range, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Distribution_Range_fields[3] = {
+    PB_FIELD(  1, DOUBLE  , OPTIONAL, STATIC  , FIRST, google_census_Distribution_Range, min, min, 0),
+    PB_FIELD(  2, DOUBLE  , OPTIONAL, STATIC  , OTHER, google_census_Distribution_Range, max, min, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_IntervalStats_fields[2] = {
+    PB_FIELD(  1, MESSAGE , REPEATED, CALLBACK, FIRST, google_census_IntervalStats, window, window, &google_census_IntervalStats_Window_fields),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_IntervalStats_Window_fields[4] = {
+    PB_FIELD(  1, MESSAGE , OPTIONAL, STATIC  , FIRST, google_census_IntervalStats_Window, window_size, window_size, &google_census_Duration_fields),
+    PB_FIELD(  2, INT64   , OPTIONAL, STATIC  , OTHER, google_census_IntervalStats_Window, count, window_size, 0),
+    PB_FIELD(  3, DOUBLE  , OPTIONAL, STATIC  , OTHER, google_census_IntervalStats_Window, mean, count, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Tag_fields[3] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, STATIC  , FIRST, google_census_Tag, key, key, 0),
+    PB_FIELD(  2, STRING  , OPTIONAL, STATIC  , OTHER, google_census_Tag, value, key, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_View_fields[6] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, CALLBACK, FIRST, google_census_View, name, name, 0),
+    PB_FIELD(  2, STRING  , OPTIONAL, CALLBACK, OTHER, google_census_View, description, name, 0),
+    PB_FIELD(  3, INT32   , OPTIONAL, STATIC  , OTHER, google_census_View, metric_id, description, 0),
+    PB_FIELD(  4, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_View, aggregation, metric_id, &google_census_AggregationDescriptor_fields),
+    PB_FIELD(  5, STRING  , REPEATED, CALLBACK, OTHER, google_census_View, tag_key, aggregation, 0),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_Aggregation_fields[6] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, CALLBACK, FIRST, google_census_Aggregation, name, name, 0),
+    PB_FIELD(  2, STRING  , OPTIONAL, CALLBACK, OTHER, google_census_Aggregation, description, name, 0),
+    PB_ONEOF_FIELD(data,   3, MESSAGE , ONEOF, STATIC  , OTHER, google_census_Aggregation, distribution, description, &google_census_Distribution_fields),
+    PB_ONEOF_FIELD(data,   4, MESSAGE , ONEOF, STATIC  , OTHER, google_census_Aggregation, interval_stats, description, &google_census_IntervalStats_fields),
+    PB_FIELD(  5, MESSAGE , REPEATED, CALLBACK, OTHER, google_census_Aggregation, tag, data.interval_stats, &google_census_Tag_fields),
+    PB_LAST_FIELD
+};
+
+const pb_field_t google_census_ViewAggregations_fields[4] = {
+    PB_FIELD(  1, MESSAGE , REPEATED, CALLBACK, FIRST, google_census_ViewAggregations, aggregation, aggregation, &google_census_Aggregation_fields),
+    PB_FIELD(  2, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_ViewAggregations, start, aggregation, &google_census_Timestamp_fields),
+    PB_FIELD(  3, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_ViewAggregations, end, start, &google_census_Timestamp_fields),
+    PB_LAST_FIELD
+};
+
+
+/* Check that field information fits in pb_field_t */
+#if !defined(PB_FIELD_32BIT)
+/* If you get an error here, it means that you need to define PB_FIELD_32BIT
+ * compile-time option. You can do that in pb.h or on compiler command line.
+ * 
+ * The reason you need to do this is that some of your messages contain tag
+ * numbers or field sizes that are larger than what can fit in 8 or 16 bit
+ * field descriptors.
+ */
+PB_STATIC_ASSERT((pb_membersize(google_census_Metric, unit) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Metric, unit) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Distribution, range) < 65536 && pb_membersize(google_census_IntervalStats, window) < 65536 && pb_membersize(google_census_IntervalStats_Window, window_size) < 65536 && pb_membersize(google_census_View, aggregation) < 65536 && pb_membersize(google_census_Aggregation, data.distribution) < 65536 && pb_membersize(google_census_Aggregation, data.interval_stats) < 65536 && pb_membersize(google_census_Metric, unit) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Metric, unit) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 65536 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Distribution, range) < 65536 && pb_membersize(google_census_IntervalStats, window) < 65536 && pb_membersize(google_census_IntervalStats_Window, window_size) < 65536 && pb_membersize(google_census_View, aggregation) < 65536 && pb_membersize(google_census_Aggregation, data.distribution) < 65536 && pb_membersize(google_census_Aggregation, data.interval_stats) < 65536 && pb_membersize(google_census_Aggregation, tag) < 65536 && pb_membersize(google_census_ViewAggregations, aggregation) < 65536 && pb_membersize(google_census_ViewAggregations, start) < 65536 && pb_membersize(google_census_ViewAggregations, end) < 65536), YOU_MUST_DEFINE_PB_FIELD_32BIT_FOR_MESSAGES_google_census_Duration_google_census_Timestamp_google_census_Metric_google_census_Metric_BasicUnit_google_census_Metric_MeasurementUnit_google_census_AggregationDescriptor_google_census_AggregationDescriptor_BucketBoundaries_google_census_AggregationDescriptor_IntervalBoundaries_google_census_Distribution_google_census_Distribution_Range_google_census_IntervalStats_google_census_IntervalStats_Window_google_census_Tag_google_census_View_google_census_Aggregation_google_census_ViewAggregations)
+#endif
+
+#if !defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)
+/* If you get an error here, it means that you need to define PB_FIELD_16BIT
+ * compile-time option. You can do that in pb.h or on compiler command line.
+ * 
+ * The reason you need to do this is that some of your messages contain tag
+ * numbers or field sizes that are larger than what can fit in the default
+ * 8 bit descriptors.
+ */
+PB_STATIC_ASSERT((pb_membersize(google_census_Metric, unit) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Metric, unit) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Distribution, range) < 256 && pb_membersize(google_census_IntervalStats, window) < 256 && pb_membersize(google_census_IntervalStats_Window, window_size) < 256 && pb_membersize(google_census_View, aggregation) < 256 && pb_membersize(google_census_Aggregation, data.distribution) < 256 && pb_membersize(google_census_Aggregation, data.interval_stats) < 256 && pb_membersize(google_census_Metric, unit) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Metric, unit) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, numerator) < 256 && pb_membersize(google_census_Metric_MeasurementUnit, denominator) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Distribution, range) < 256 && pb_membersize(google_census_IntervalStats, window) < 256 && pb_membersize(google_census_IntervalStats_Window, window_size) < 256 && pb_membersize(google_census_View, aggregation) < 256 && pb_membersize(google_census_Aggregation, data.distribution) < 256 && pb_membersize(google_census_Aggregation, data.interval_stats) < 256 && pb_membersize(google_census_Aggregation, tag) < 256 && pb_membersize(google_census_ViewAggregations, aggregation) < 256 && pb_membersize(google_census_ViewAggregations, start) < 256 && pb_membersize(google_census_ViewAggregations, end) < 256), YOU_MUST_DEFINE_PB_FIELD_16BIT_FOR_MESSAGES_google_census_Duration_google_census_Timestamp_google_census_Metric_google_census_Metric_BasicUnit_google_census_Metric_MeasurementUnit_google_census_AggregationDescriptor_google_census_AggregationDescriptor_BucketBoundaries_google_census_AggregationDescriptor_IntervalBoundaries_google_census_Distribution_google_census_Distribution_Range_google_census_IntervalStats_google_census_IntervalStats_Window_google_census_Tag_google_census_View_google_census_Aggregation_google_census_ViewAggregations)
+#endif
+
+
+/* On some platforms (such as AVR), double is really float.
+ * These are not directly supported by nanopb, but see example_avr_double.
+ * To get rid of this error, remove any double fields from your .proto.
+ */
+PB_STATIC_ASSERT(sizeof(double) == 8, DOUBLE_MUST_BE_8_BYTES)
+
diff --git a/src/core/ext/census/gen/census.pb.h b/src/core/ext/census/gen/census.pb.h
new file mode 100644
index 0000000000..d040fe29e7
--- /dev/null
+++ b/src/core/ext/census/gen/census.pb.h
@@ -0,0 +1,294 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+/* Automatically generated nanopb header */
+/* Generated by nanopb-0.3.5-dev */
+
+#ifndef GRPC_CORE_EXT_CENSUS_GEN_CENSUS_PB_H
+#define GRPC_CORE_EXT_CENSUS_GEN_CENSUS_PB_H
+#include "third_party/nanopb/pb.h"
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Enum definitions */
+typedef enum _google_census_Metric_BasicUnit_Measure {
+    google_census_Metric_BasicUnit_Measure_UNKNOWN = 0,
+    google_census_Metric_BasicUnit_Measure_BITS = 1,
+    google_census_Metric_BasicUnit_Measure_BYTES = 2,
+    google_census_Metric_BasicUnit_Measure_SECS = 3,
+    google_census_Metric_BasicUnit_Measure_CORES = 4,
+    google_census_Metric_BasicUnit_Measure_MAX_UNITS = 5
+} google_census_Metric_BasicUnit_Measure;
+
+/* Struct definitions */
+typedef struct _google_census_AggregationDescriptor_BucketBoundaries {
+    pb_callback_t bounds;
+} google_census_AggregationDescriptor_BucketBoundaries;
+
+typedef struct _google_census_AggregationDescriptor_IntervalBoundaries {
+    pb_callback_t window_size;
+} google_census_AggregationDescriptor_IntervalBoundaries;
+
+typedef struct _google_census_IntervalStats {
+    pb_callback_t window;
+} google_census_IntervalStats;
+
+typedef struct _google_census_AggregationDescriptor {
+    pb_size_t which_options;
+    union {
+        google_census_AggregationDescriptor_BucketBoundaries bucket_boundaries;
+        google_census_AggregationDescriptor_IntervalBoundaries interval_boundaries;
+    } options;
+} google_census_AggregationDescriptor;
+
+typedef struct _google_census_Distribution_Range {
+    bool has_min;
+    double min;
+    bool has_max;
+    double max;
+} google_census_Distribution_Range;
+
+typedef struct _google_census_Duration {
+    bool has_seconds;
+    int64_t seconds;
+    bool has_nanos;
+    int32_t nanos;
+} google_census_Duration;
+
+typedef struct _google_census_Metric_BasicUnit {
+    bool has_type;
+    google_census_Metric_BasicUnit_Measure type;
+} google_census_Metric_BasicUnit;
+
+typedef struct _google_census_Metric_MeasurementUnit {
+    bool has_prefix;
+    int32_t prefix;
+    pb_callback_t numerator;
+    pb_callback_t denominator;
+} google_census_Metric_MeasurementUnit;
+
+typedef struct _google_census_Tag {
+    bool has_key;
+    char key[255];
+    bool has_value;
+    char value[255];
+} google_census_Tag;
+
+typedef struct _google_census_Timestamp {
+    bool has_seconds;
+    int64_t seconds;
+    bool has_nanos;
+    int32_t nanos;
+} google_census_Timestamp;
+
+typedef struct _google_census_Distribution {
+    bool has_count;
+    int64_t count;
+    bool has_mean;
+    double mean;
+    bool has_range;
+    google_census_Distribution_Range range;
+    pb_callback_t bucket_count;
+} google_census_Distribution;
+
+typedef struct _google_census_IntervalStats_Window {
+    bool has_window_size;
+    google_census_Duration window_size;
+    bool has_count;
+    int64_t count;
+    bool has_mean;
+    double mean;
+} google_census_IntervalStats_Window;
+
+typedef struct _google_census_Metric {
+    pb_callback_t name;
+    pb_callback_t description;
+    bool has_unit;
+    google_census_Metric_MeasurementUnit unit;
+    bool has_id;
+    int32_t id;
+} google_census_Metric;
+
+typedef struct _google_census_View {
+    pb_callback_t name;
+    pb_callback_t description;
+    bool has_metric_id;
+    int32_t metric_id;
+    bool has_aggregation;
+    google_census_AggregationDescriptor aggregation;
+    pb_callback_t tag_key;
+} google_census_View;
+
+typedef struct _google_census_ViewAggregations {
+    pb_callback_t aggregation;
+    bool has_start;
+    google_census_Timestamp start;
+    bool has_end;
+    google_census_Timestamp end;
+} google_census_ViewAggregations;
+
+typedef struct _google_census_Aggregation {
+    pb_callback_t name;
+    pb_callback_t description;
+    pb_size_t which_data;
+    union {
+        google_census_Distribution distribution;
+        google_census_IntervalStats interval_stats;
+    } data;
+    pb_callback_t tag;
+} google_census_Aggregation;
+
+/* Default values for struct fields */
+
+/* Initializer values for message structs */
+#define google_census_Duration_init_default      {false, 0, false, 0}
+#define google_census_Timestamp_init_default     {false, 0, false, 0}
+#define google_census_Metric_init_default        {{{NULL}, NULL}, {{NULL}, NULL}, false, google_census_Metric_MeasurementUnit_init_default, false, 0}
+#define google_census_Metric_BasicUnit_init_default {false, (google_census_Metric_BasicUnit_Measure)0}
+#define google_census_Metric_MeasurementUnit_init_default {false, 0, {{NULL}, NULL}, {{NULL}, NULL}}
+#define google_census_AggregationDescriptor_init_default {0, {google_census_AggregationDescriptor_BucketBoundaries_init_default}}
+#define google_census_AggregationDescriptor_BucketBoundaries_init_default {{{NULL}, NULL}}
+#define google_census_AggregationDescriptor_IntervalBoundaries_init_default {{{NULL}, NULL}}
+#define google_census_Distribution_init_default  {false, 0, false, 0, false, google_census_Distribution_Range_init_default, {{NULL}, NULL}}
+#define google_census_Distribution_Range_init_default {false, 0, false, 0}
+#define google_census_IntervalStats_init_default {{{NULL}, NULL}}
+#define google_census_IntervalStats_Window_init_default {false, google_census_Duration_init_default, false, 0, false, 0}
+#define google_census_Tag_init_default           {false, "", false, ""}
+#define google_census_View_init_default          {{{NULL}, NULL}, {{NULL}, NULL}, false, 0, false, google_census_AggregationDescriptor_init_default, {{NULL}, NULL}}
+#define google_census_Aggregation_init_default   {{{NULL}, NULL}, {{NULL}, NULL}, 0, {google_census_Distribution_init_default}, {{NULL}, NULL}}
+#define google_census_ViewAggregations_init_default {{{NULL}, NULL}, false, google_census_Timestamp_init_default, false, google_census_Timestamp_init_default}
+#define google_census_Duration_init_zero         {false, 0, false, 0}
+#define google_census_Timestamp_init_zero        {false, 0, false, 0}
+#define google_census_Metric_init_zero           {{{NULL}, NULL}, {{NULL}, NULL}, false, google_census_Metric_MeasurementUnit_init_zero, false, 0}
+#define google_census_Metric_BasicUnit_init_zero {false, (google_census_Metric_BasicUnit_Measure)0}
+#define google_census_Metric_MeasurementUnit_init_zero {false, 0, {{NULL}, NULL}, {{NULL}, NULL}}
+#define google_census_AggregationDescriptor_init_zero {0, {google_census_AggregationDescriptor_BucketBoundaries_init_zero}}
+#define google_census_AggregationDescriptor_BucketBoundaries_init_zero {{{NULL}, NULL}}
+#define google_census_AggregationDescriptor_IntervalBoundaries_init_zero {{{NULL}, NULL}}
+#define google_census_Distribution_init_zero     {false, 0, false, 0, false, google_census_Distribution_Range_init_zero, {{NULL}, NULL}}
+#define google_census_Distribution_Range_init_zero {false, 0, false, 0}
+#define google_census_IntervalStats_init_zero    {{{NULL}, NULL}}
+#define google_census_IntervalStats_Window_init_zero {false, google_census_Duration_init_zero, false, 0, false, 0}
+#define google_census_Tag_init_zero              {false, "", false, ""}
+#define google_census_View_init_zero             {{{NULL}, NULL}, {{NULL}, NULL}, false, 0, false, google_census_AggregationDescriptor_init_zero, {{NULL}, NULL}}
+#define google_census_Aggregation_init_zero      {{{NULL}, NULL}, {{NULL}, NULL}, 0, {google_census_Distribution_init_zero}, {{NULL}, NULL}}
+#define google_census_ViewAggregations_init_zero {{{NULL}, NULL}, false, google_census_Timestamp_init_zero, false, google_census_Timestamp_init_zero}
+
+/* Field tags (for use in manual encoding/decoding) */
+#define google_census_AggregationDescriptor_BucketBoundaries_bounds_tag 1
+#define google_census_AggregationDescriptor_IntervalBoundaries_window_size_tag 1
+#define google_census_IntervalStats_window_tag   1
+#define google_census_AggregationDescriptor_bucket_boundaries_tag 1
+
+#define google_census_AggregationDescriptor_interval_boundaries_tag 2
+#define google_census_Distribution_Range_min_tag 1
+#define google_census_Distribution_Range_max_tag 2
+#define google_census_Duration_seconds_tag       1
+#define google_census_Duration_nanos_tag         2
+#define google_census_Metric_BasicUnit_type_tag  1
+#define google_census_Metric_MeasurementUnit_prefix_tag 1
+#define google_census_Metric_MeasurementUnit_numerator_tag 2
+#define google_census_Metric_MeasurementUnit_denominator_tag 3
+#define google_census_Tag_key_tag                1
+#define google_census_Tag_value_tag              2
+#define google_census_Timestamp_seconds_tag      1
+#define google_census_Timestamp_nanos_tag        2
+#define google_census_Distribution_count_tag     1
+#define google_census_Distribution_mean_tag      2
+#define google_census_Distribution_range_tag     3
+#define google_census_Distribution_bucket_count_tag 4
+#define google_census_IntervalStats_Window_window_size_tag 1
+#define google_census_IntervalStats_Window_count_tag 2
+#define google_census_IntervalStats_Window_mean_tag 3
+#define google_census_Metric_name_tag            1
+#define google_census_Metric_description_tag     2
+#define google_census_Metric_unit_tag            3
+#define google_census_Metric_id_tag              4
+#define google_census_View_name_tag              1
+#define google_census_View_description_tag       2
+#define google_census_View_metric_id_tag         3
+#define google_census_View_aggregation_tag       4
+#define google_census_View_tag_key_tag           5
+#define google_census_ViewAggregations_aggregation_tag 1
+#define google_census_ViewAggregations_start_tag 2
+#define google_census_ViewAggregations_end_tag   3
+#define google_census_Aggregation_distribution_tag 3
+
+#define google_census_Aggregation_interval_stats_tag 4
+#define google_census_Aggregation_name_tag       1
+#define google_census_Aggregation_description_tag 2
+#define google_census_Aggregation_tag_tag        5
+
+/* Struct field encoding specification for nanopb */
+extern const pb_field_t google_census_Duration_fields[3];
+extern const pb_field_t google_census_Timestamp_fields[3];
+extern const pb_field_t google_census_Metric_fields[5];
+extern const pb_field_t google_census_Metric_BasicUnit_fields[2];
+extern const pb_field_t google_census_Metric_MeasurementUnit_fields[4];
+extern const pb_field_t google_census_AggregationDescriptor_fields[3];
+extern const pb_field_t google_census_AggregationDescriptor_BucketBoundaries_fields[2];
+extern const pb_field_t google_census_AggregationDescriptor_IntervalBoundaries_fields[2];
+extern const pb_field_t google_census_Distribution_fields[5];
+extern const pb_field_t google_census_Distribution_Range_fields[3];
+extern const pb_field_t google_census_IntervalStats_fields[2];
+extern const pb_field_t google_census_IntervalStats_Window_fields[4];
+extern const pb_field_t google_census_Tag_fields[3];
+extern const pb_field_t google_census_View_fields[6];
+extern const pb_field_t google_census_Aggregation_fields[6];
+extern const pb_field_t google_census_ViewAggregations_fields[4];
+
+/* Maximum encoded size of messages (where known) */
+#define google_census_Duration_size              22
+#define google_census_Timestamp_size             22
+#define google_census_Metric_BasicUnit_size      2
+#define google_census_Distribution_Range_size    18
+#define google_census_IntervalStats_Window_size  44
+#define google_census_Tag_size                   516
+
+/* Message IDs (where set with "msgid" option) */
+#ifdef PB_MSGID
+
+#define CENSUS_MESSAGES \
+
+
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif
diff --git a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h b/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
index d5dc39ab94..46fe588f72 100644
--- a/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
+++ b/src/core/ext/lb_policy/grpclb/proto/grpc/lb/v1/load_balancer.pb.h
@@ -33,8 +33,8 @@
 /* Automatically generated nanopb header */
 /* Generated by nanopb-0.3.5-dev */
 
-#ifndef PB_LOAD_BALANCER_PB_H_INCLUDED
-#define PB_LOAD_BALANCER_PB_H_INCLUDED
+#ifndef GRPC_CORE_EXT_LB_POLICY_GRPCLB_PROTO_GRPC_LB_V1_LOAD_BALANCER_PB_H
+#define GRPC_CORE_EXT_LB_POLICY_GRPCLB_PROTO_GRPC_LB_V1_LOAD_BALANCER_PB_H
 #include "third_party/nanopb/pb.h"
 #if PB_PROTO_HEADER_VERSION != 30
 #error Regenerate this file with the current version of nanopb generator.
diff --git a/src/proto/census/census.options b/src/proto/census/census.options
new file mode 100644
index 0000000000..a1f80395c7
--- /dev/null
+++ b/src/proto/census/census.options
@@ -0,0 +1,3 @@
+google.census.Tag.key max_size:255
+google.census.Tag.value max_size:255
+google.census.View.tag_key max_count:15
diff --git a/src/proto/census/census.proto b/src/proto/census/census.proto
new file mode 100644
index 0000000000..c869d851ff
--- /dev/null
+++ b/src/proto/census/census.proto
@@ -0,0 +1,313 @@
+// Copyright 2016, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+syntax = "proto3";
+
+package google.census;
+
+// All the census protos.
+//
+// Nomenclature note: capitalized names below (like Metric) are protos.
+//
+// Census lets you define a Metric - something which can be measured, like the
+// latency of an RPC, the number of CPU cycles spent on an operation, or
+// anything else you care to measure. You can record individual instances of
+// measurements (a double value) for every metric of interest. These
+// individual measurements are aggregated together into an Aggregation. There
+// are two Aggregation types available: Distribution (describes the
+// distribution of all measurements, possibly with a histogram) and
+// IntervalStats (the count and mean of measurements across specified time
+// periods). An Aggregation is described by an AggregationDescriptor.
+//
+// You can define how your stats are broken down by Tag values and which
+// Aggregations to use through a View. The corresponding combination of
+// Metric/View/Aggregation which is available to census clients is called a
+// ViewAggregation.
+
+
+// The following two types are copied from
+// google/protobuf/{duration,timestamp}.proto. Ideally, we would be able to
+// import them, but this causes compilation issues on C-based systems
+// (e.g. https://koti.kapsi.fi/jpa/nanopb/), which cannot process the C++
+// headers generated from the standard protobuf distribution. See the relevant
+// proto files for full documentation of these types.
+
+message Duration {
+  // Signed seconds of the span of time. Must be from -315,576,000,000
+  // to +315,576,000,000 inclusive.
+  int64 seconds = 1;
+
+  // Signed fractions of a second at nanosecond resolution of the span
+  // of time. Durations less than one second are represented with a 0
+  // `seconds` field and a positive or negative `nanos` field. For durations
+  // of one second or more, a non-zero value for the `nanos` field must be
+  // of the same sign as the `seconds` field. Must be from -999,999,999
+  // to +999,999,999 inclusive.
+  int32 nanos = 2;
+}
+
+message Timestamp {
+  // Represents seconds of UTC time since Unix epoch
+  // 1970-01-01T00:00:00Z. Must be from from 0001-01-01T00:00:00Z to
+  // 9999-12-31T23:59:59Z inclusive.
+  int64 seconds = 1;
+
+  // Non-negative fractions of a second at nanosecond resolution. Negative
+  // second values with fractions must still have non-negative nanos values
+  // that count forward in time. Must be from 0 to 999,999,999
+  // inclusive.
+  int32 nanos = 2;
+}
+
+// Describes a metric
+message Metric {
+  // name of metric, e.g. rpc_latency, cpu.
+  string name = 1;
+
+  // More detailed description of the metric, used in documentation.
+  string description = 2;
+
+  // Fundamental units of measurement supported by Census
+  // TODO(aveitch): expand this to include other S.I. units?
+  message BasicUnit {
+    enum Measure {
+      UNKNOWN = 0;
+      BITS = 1;
+      BYTES = 2;
+      SECS = 3;
+      CORES = 4;
+      MAX_UNITS = 5;
+    }
+    Measure type = 1;
+  }
+
+  // MeasurementUnit lets you build compound units of the form
+  //   10^n * (A * B * ...) / (X * Y * ...),
+  // where the elements in the numerator and denominator are all BasicUnits.  A
+  // MeasurementUnit must have at least one BasicUnit in its numerator.
+  //
+  // To specify multiplication in the numerator or denominator, simply specify
+  // multiple numerator or denominator fields.  For example:
+  //
+  // - byte-seconds (i.e. bytes * seconds):
+  //     numerator: BYTES
+  //     numerator: SECS
+  //
+  // - events/sec^2 (i.e. rate of change of events/sec):
+  //     numerator: COUNT
+  //     denominator: SECS
+  //     denominator: SECS
+  //
+  // To specify multiples (in power of 10) units, specify a non-zero prefix
+  // value, for example:
+  //
+  // - MB/s (i.e. megabytes / s):
+  //     prefix: 6
+  //     numerator: BYTES
+  //     denominator: SECS
+  //
+  // - nanoseconds
+  //     prefix: -9
+  //     numerator: SECS
+  message MeasurementUnit {
+    int32 prefix = 1;
+    repeated BasicUnit numerator = 2;
+    repeated BasicUnit denominator = 3;
+  }
+
+  // The units in which the Metric value is reported.
+  MeasurementUnit unit = 3;
+
+  // Metrics will be assigned an ID when registered. Invalid if <= 0.
+  int32 id = 4;
+}
+
+// An Aggregation summarizes a series of individual Metric measurements, an
+// AggregationDescriptor describes an Aggregation.
+message AggregationDescriptor {
+  // At most one set of options. If neither option is set, a default type
+  // of Distribution (without a histogram component) will be used.
+  oneof options {
+    // Defines the histogram bucket boundaries for Distributions.
+    BucketBoundaries bucket_boundaries = 1;
+    // Defines the time windows to record for IntervalStats.
+    IntervalBoundaries interval_boundaries = 2;
+  }
+
+  // A Distribution may optionally contain a histogram of the values in the
+  // population. The bucket boundaries for that histogram is described by
+  // `bucket_boundaries`.
+  //
+  // Describes histogram bucket boundaries. Defines `size(bounds) + 1` (= N)
+  // buckets (for size(bounds) >= 1; if size(bounds) == 0, then no histogram
+  // will be defined. The boundaries for bucket index i are:
+  //
+  // [-infinity, bounds[i]) for i == 0
+  // [bounds[i-1], bounds[i]) for 0 < i < N-2
+  // [bounds[i-1], +infinity) for i == N-1
+  //
+  // i.e. an underflow bucket (number 0), zero or more finite buckets (1
+  // through N - 2, and an overflow bucket (N - 1), with inclusive lower
+  // bounds and exclusive upper bounds.
+  //
+  // There must be at least one element in `bounds`.  If `bounds` has only one
+  // element, there are no finite buckets, and that single element is the
+  // common boundary of the overflow and underflow buckets.
+  message BucketBoundaries {
+    // The values must be monotonically increasing.
+    repeated double bounds = 1;
+  }
+
+  // For Interval stats, describe the size of each window.
+  message IntervalBoundaries {
+    // For each time window, specify a duration in seconds.
+    repeated double window_size = 1;
+  }
+}
+
+// Distribution contains summary statistics for a population of values and,
+// optionally, a histogram representing the distribution of those values across
+// a specified set of histogram buckets, as defined in
+// Aggregation.bucket_options.
+//
+// The summary statistics are the count, mean, sum of the squared deviation from
+// the mean, the minimum, and the maximum of the set of population of values.
+//
+// Although it is not forbidden, it is generally a bad idea to include
+// non-finite values (infinities or NaNs) in the population of values, as this
+// will render the `mean` field meaningless.
+message Distribution {
+  // The number of values in the population. Must be non-negative.
+  int64 count = 1;
+
+  // The arithmetic mean of the values in the population. If `count` is zero
+  // then this field must be zero.
+  double mean = 2;
+
+  // Describes a range of population values.
+  message Range {
+    // The minimum of the population values.
+    double min = 1;
+    // The maximum of the population values.
+    double max = 2;
+  }
+
+  // The range of the population values. If `count` is zero, this field will not
+  // be defined.
+  Range range = 3;
+
+  // A Distribution may optionally contain a histogram of the values in the
+  // population.  The histogram is given in `bucket_count` as counts of values
+  // that fall into one of a sequence of non-overlapping buckets, as described
+  // by `AggregationDescriptor.options.bucket_boundaries`.
+  // The sum of the values in `bucket_counts` must equal the value in `count`.
+  //
+  // Bucket counts are given in order under the numbering scheme described
+  // above (the underflow bucket has number 0; the finite buckets, if any,
+  // have numbers 1 through N-2; the overflow bucket has number N-1).
+  //
+  // The size of `bucket_count` must be no greater than N as defined in
+  // `bucket_boundaries`.
+  //
+  // Any suffix of trailing zero bucket_count fields may be omitted.
+  repeated int64 bucket_count = 4;
+}
+
+// Record summary stats over various time windows.
+message IntervalStats {
+  // Summary statistic over a single time window.
+  message Window {
+    // The window duration.
+    Duration window_size = 1;
+    // The number of measurements in this window.
+    int64 count = 2;
+    // The arithmetic mean of all measurements in the window.
+    double mean = 3;
+  }
+
+  // Full set of windows for this metric.
+  repeated Window window = 1;
+}
+
+// A Tag: key-value pair.
+message Tag {
+  string key = 1;
+  string value = 2;
+}
+
+// A View specifies an Aggregation and a set of tag keys. The Aggregation will
+// be broken down by the unique set of matching tag values for each measurement.
+message View {
+  // Name of view.
+  string name = 1;
+
+  // More detailed description, for documentation purposes.
+  string description = 2;
+
+  // ID of Metric to associate with this View.
+  int32 metric_id = 3;
+
+  // Aggregation type to associate with this View.
+  AggregationDescriptor aggregation = 4;
+
+  // Tag keys to match with a given Metric. If no keys are specified, then all
+  // stats for the Metric are recorded. Keys must be unique.
+  repeated string tag_key = 5;
+}
+
+// An Aggregation summarizes a series of individual Metric measures.
+message Aggregation {
+  // Name of this aggregation.
+  string name = 1;
+
+  // More detailed description, for documentation purposes.
+  string description = 2;
+
+  // The data for this Aggregation.
+  oneof data {
+    Distribution distribution = 3;
+    IntervalStats interval_stats = 4;
+  }
+
+  // Tags associated with this Aggregation.
+  repeated Tag tag = 5;
+}
+
+// A ViewAggregations represents all the Aggregations for a particular view.
+message ViewAggregations {
+  // Aggregations - each will have a unique set of tag values for the tag_keys
+  // associated with the corresponding View.
+  repeated Aggregation aggregation = 1;
+
+  // Start and end timestamps over which the value was accumulated. These
+  // values are not relevant/defined for IntervalStats aggregations, which are
+  // always accumulated over a fixed time period.
+  Timestamp start = 2;
+  Timestamp end = 3;
+}
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 9c067add0a..d0f23f42cc 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -244,6 +244,7 @@ CORE_SOURCE_FILES = [
   'src/core/ext/resolver/dns/native/dns_resolver.c',
   'src/core/ext/resolver/sockaddr/sockaddr_resolver.c',
   'src/core/ext/census/context.c',
+  'src/core/ext/census/gen/census.pb.c',
   'src/core/ext/census/grpc_context.c',
   'src/core/ext/census/grpc_filter.c',
   'src/core/ext/census/grpc_plugin.c',