Merge remote-tracking branch 'upstream/master' into cares

9 files changed, 605 insertions, 153 deletions

diff --git a/src/core/ext/census/base_resources.c b/src/core/ext/census/base_resources.c
new file mode 100644
index 0000000000..f9aa4bb994
--- /dev/null
+++ b/src/core/ext/census/base_resources.c
@@ -0,0 +1,71 @@
+/*
+ * 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.
+ *
+ */
+
+#include "src/core/ext/census/base_resources.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#include <grpc/census.h>
+#include <grpc/support/log.h>
+
+#include "src/core/ext/census/resource.h"
+
+// Add base RPC resource definitions for use by RPC runtime.
+//
+// TODO(aveitch): All of these are currently hardwired definitions encoded in
+// the code in this file. These should be converted to use an external
+// configuration mechanism, in which these resources are defined in a text
+// file, which is compiled to .pb format and read by still-to-be-written
+// configuration functions.
+
+// Define all base resources. This should be called by census initialization.
+void define_base_resources() {
+  google_census_Resource_BasicUnit numerator =
+      google_census_Resource_BasicUnit_SECS;
+  resource r = {"client_rpc_latency",             // name
+                "Client RPC latency in seconds",  // description
+                0,                                // prefix
+                1,                                // n_numerators
+                &numerator,                       // numerators
+                0,                                // n_denominators
+                NULL};                            // denominators
+  define_resource(&r);
+  r = (resource){"server_rpc_latency",             // name
+                 "Server RPC latency in seconds",  // description
+                 0,                                // prefix
+                 1,                                // n_numerators
+                 &numerator,                       // numerators
+                 0,                                // n_denominators
+                 NULL};                            // denominators
+  define_resource(&r);
+}
diff --git a/src/core/ext/census/base_resources.h b/src/core/ext/census/base_resources.h
new file mode 100644
index 0000000000..e5a7696db4
--- /dev/null
+++ b/src/core/ext/census/base_resources.h
@@ -0,0 +1,39 @@
+/*
+ * 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.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_CENSUS_BASE_RESOURCES_H
+#define GRPC_CORE_EXT_CENSUS_BASE_RESOURCES_H
+
+/* Define all base resources. This should be called by census initialization. */
+void define_base_resources();
+
+#endif /* GRPC_CORE_EXT_CENSUS_BASE_RESOURCES_H */
diff --git a/src/core/ext/census/gen/census.pb.c b/src/core/ext/census/gen/census.pb.c
index d614636c90..647f0635b7 100644
--- a/src/core/ext/census/gen/census.pb.c
+++ b/src/core/ext/census/gen/census.pb.c
@@ -53,29 +53,24 @@ const pb_field_t google_census_Timestamp_fields[3] = {
     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),
+const pb_field_t google_census_Resource_fields[4] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, CALLBACK, FIRST, google_census_Resource, name, name, 0),
+    PB_FIELD(  2, STRING  , OPTIONAL, CALLBACK, OTHER, google_census_Resource, description, name, 0),
+    PB_FIELD(  3, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_Resource, unit, description, &google_census_Resource_MeasurementUnit_fields),
     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),
+const pb_field_t google_census_Resource_MeasurementUnit_fields[4] = {
+    PB_FIELD(  1, INT32   , OPTIONAL, STATIC  , FIRST, google_census_Resource_MeasurementUnit, prefix, prefix, 0),
+    PB_FIELD(  2, UENUM   , REPEATED, CALLBACK, OTHER, google_census_Resource_MeasurementUnit, numerator, prefix, 0),
+    PB_FIELD(  3, UENUM   , REPEATED, CALLBACK, OTHER, google_census_Resource_MeasurementUnit, denominator, numerator, 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),
+const pb_field_t google_census_AggregationDescriptor_fields[4] = {
+    PB_FIELD(  1, UENUM   , OPTIONAL, STATIC  , FIRST, google_census_AggregationDescriptor, type, type, 0),
+    PB_ONEOF_FIELD(options,   2, MESSAGE , ONEOF, STATIC  , OTHER, google_census_AggregationDescriptor, bucket_boundaries, type, &google_census_AggregationDescriptor_BucketBoundaries_fields),
+    PB_ONEOF_FIELD(options,   3, MESSAGE , ONEOF, STATIC  , OTHER, google_census_AggregationDescriptor, interval_boundaries, type, &google_census_AggregationDescriptor_IntervalBoundaries_fields),
     PB_LAST_FIELD
 };
 
@@ -124,25 +119,27 @@ const pb_field_t google_census_Tag_fields[3] = {
 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(  3, STRING  , OPTIONAL, CALLBACK, OTHER, google_census_View, resource_name, description, 0),
+    PB_FIELD(  4, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_View, aggregation, resource_name, &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] = {
+const pb_field_t google_census_Aggregation_fields[7] = {
     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_ONEOF_FIELD(data,   3, UINT64  , ONEOF, STATIC  , OTHER, google_census_Aggregation, count, description, 0),
+    PB_ONEOF_FIELD(data,   4, MESSAGE , ONEOF, STATIC  , OTHER, google_census_Aggregation, distribution, description, &google_census_Distribution_fields),
+    PB_ONEOF_FIELD(data,   5, MESSAGE , ONEOF, STATIC  , OTHER, google_census_Aggregation, interval_stats, description, &google_census_IntervalStats_fields),
+    PB_FIELD(  6, 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),
+const pb_field_t google_census_Metric_fields[5] = {
+    PB_FIELD(  1, STRING  , OPTIONAL, CALLBACK, FIRST, google_census_Metric, view_name, view_name, 0),
+    PB_FIELD(  2, MESSAGE , REPEATED, CALLBACK, OTHER, google_census_Metric, aggregation, view_name, &google_census_Aggregation_fields),
+    PB_FIELD(  3, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_Metric, start, aggregation, &google_census_Timestamp_fields),
+    PB_FIELD(  4, MESSAGE , OPTIONAL, STATIC  , OTHER, google_census_Metric, end, start, &google_census_Timestamp_fields),
     PB_LAST_FIELD
 };
 
@@ -156,7 +153,7 @@ const pb_field_t google_census_ViewAggregations_fields[4] = {
  * 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)
+PB_STATIC_ASSERT((pb_membersize(google_census_Resource, unit) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Resource, unit) < 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_Resource, unit) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 65536 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 65536 && pb_membersize(google_census_Resource, unit) < 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_Metric, aggregation) < 65536 && pb_membersize(google_census_Metric, start) < 65536 && pb_membersize(google_census_Metric, end) < 65536), YOU_MUST_DEFINE_PB_FIELD_32BIT_FOR_MESSAGES_google_census_Duration_google_census_Timestamp_google_census_Resource_google_census_Resource_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_Metric)
 #endif
 
 #if !defined(PB_FIELD_16BIT) && !defined(PB_FIELD_32BIT)
@@ -167,7 +164,7 @@ PB_STATIC_ASSERT((pb_membersize(google_census_Metric, unit) < 65536 && pb_member
  * 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)
+PB_STATIC_ASSERT((pb_membersize(google_census_Resource, unit) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Resource, unit) < 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_Resource, unit) < 256 && pb_membersize(google_census_AggregationDescriptor, options.bucket_boundaries) < 256 && pb_membersize(google_census_AggregationDescriptor, options.interval_boundaries) < 256 && pb_membersize(google_census_Resource, unit) < 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_Metric, aggregation) < 256 && pb_membersize(google_census_Metric, start) < 256 && pb_membersize(google_census_Metric, end) < 256), YOU_MUST_DEFINE_PB_FIELD_16BIT_FOR_MESSAGES_google_census_Duration_google_census_Timestamp_google_census_Resource_google_census_Resource_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_Metric)
 #endif
 
 
diff --git a/src/core/ext/census/gen/census.pb.h b/src/core/ext/census/gen/census.pb.h
index d040fe29e7..dae583f33d 100644
--- a/src/core/ext/census/gen/census.pb.h
+++ b/src/core/ext/census/gen/census.pb.h
@@ -45,14 +45,21 @@ 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;
+typedef enum _google_census_Resource_BasicUnit {
+    google_census_Resource_BasicUnit_UNKNOWN = 0,
+    google_census_Resource_BasicUnit_BITS = 1,
+    google_census_Resource_BasicUnit_BYTES = 2,
+    google_census_Resource_BasicUnit_SECS = 3,
+    google_census_Resource_BasicUnit_CORES = 4,
+    google_census_Resource_BasicUnit_MAX_UNITS = 5
+} google_census_Resource_BasicUnit;
+
+typedef enum _google_census_AggregationDescriptor_AggregationType {
+    google_census_AggregationDescriptor_AggregationType_UNKNOWN = 0,
+    google_census_AggregationDescriptor_AggregationType_COUNT = 1,
+    google_census_AggregationDescriptor_AggregationType_DISTRIBUTION = 2,
+    google_census_AggregationDescriptor_AggregationType_INTERVAL = 3
+} google_census_AggregationDescriptor_AggregationType;
 
 /* Struct definitions */
 typedef struct _google_census_AggregationDescriptor_BucketBoundaries {
@@ -68,6 +75,8 @@ typedef struct _google_census_IntervalStats {
 } google_census_IntervalStats;
 
 typedef struct _google_census_AggregationDescriptor {
+    bool has_type;
+    google_census_AggregationDescriptor_AggregationType type;
     pb_size_t which_options;
     union {
         google_census_AggregationDescriptor_BucketBoundaries bucket_boundaries;
@@ -89,17 +98,12 @@ typedef struct _google_census_Duration {
     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 {
+typedef struct _google_census_Resource_MeasurementUnit {
     bool has_prefix;
     int32_t prefix;
     pb_callback_t numerator;
     pb_callback_t denominator;
-} google_census_Metric_MeasurementUnit;
+} google_census_Resource_MeasurementUnit;
 
 typedef struct _google_census_Tag {
     bool has_key;
@@ -135,37 +139,36 @@ typedef struct _google_census_IntervalStats_Window {
 } google_census_IntervalStats_Window;
 
 typedef struct _google_census_Metric {
+    pb_callback_t view_name;
+    pb_callback_t aggregation;
+    bool has_start;
+    google_census_Timestamp start;
+    bool has_end;
+    google_census_Timestamp end;
+} google_census_Metric;
+
+typedef struct _google_census_Resource {
     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;
+    google_census_Resource_MeasurementUnit unit;
+} google_census_Resource;
 
 typedef struct _google_census_View {
     pb_callback_t name;
     pb_callback_t description;
-    bool has_metric_id;
-    int32_t metric_id;
+    pb_callback_t resource_name;
     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 {
+        uint64_t count;
         google_census_Distribution distribution;
         google_census_IntervalStats interval_stats;
     } data;
@@ -177,10 +180,9 @@ typedef struct _google_census_Aggregation {
 /* 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_Resource_init_default      {{{NULL}, NULL}, {{NULL}, NULL}, false, google_census_Resource_MeasurementUnit_init_default}
+#define google_census_Resource_MeasurementUnit_init_default {false, 0, {{NULL}, NULL}, {{NULL}, NULL}}
+#define google_census_AggregationDescriptor_init_default {false, (google_census_AggregationDescriptor_AggregationType)0, 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}}
@@ -188,15 +190,14 @@ typedef struct _google_census_Aggregation {
 #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_View_init_default          {{{NULL}, NULL}, {{NULL}, NULL}, {{NULL}, NULL}, false, google_census_AggregationDescriptor_init_default, {{NULL}, NULL}}
+#define google_census_Aggregation_init_default   {{{NULL}, NULL}, {{NULL}, NULL}, 0, {0}, {{NULL}, NULL}}
+#define google_census_Metric_init_default        {{{NULL}, NULL}, {{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_Resource_init_zero         {{{NULL}, NULL}, {{NULL}, NULL}, false, google_census_Resource_MeasurementUnit_init_zero}
+#define google_census_Resource_MeasurementUnit_init_zero {false, 0, {{NULL}, NULL}, {{NULL}, NULL}}
+#define google_census_AggregationDescriptor_init_zero {false, (google_census_AggregationDescriptor_AggregationType)0, 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}}
@@ -204,25 +205,25 @@ typedef struct _google_census_Aggregation {
 #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}
+#define google_census_View_init_zero             {{{NULL}, NULL}, {{NULL}, NULL}, {{NULL}, NULL}, false, google_census_AggregationDescriptor_init_zero, {{NULL}, NULL}}
+#define google_census_Aggregation_init_zero      {{{NULL}, NULL}, {{NULL}, NULL}, 0, {0}, {{NULL}, NULL}}
+#define google_census_Metric_init_zero           {{{NULL}, NULL}, {{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_bucket_boundaries_tag 2
 
-#define google_census_AggregationDescriptor_interval_boundaries_tag 2
+#define google_census_AggregationDescriptor_interval_boundaries_tag 3
+#define google_census_AggregationDescriptor_type_tag 1
 #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_Resource_MeasurementUnit_prefix_tag 1
+#define google_census_Resource_MeasurementUnit_numerator_tag 2
+#define google_census_Resource_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
@@ -234,32 +235,33 @@ typedef struct _google_census_Aggregation {
 #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_Metric_view_name_tag       1
+#define google_census_Metric_aggregation_tag     2
+#define google_census_Metric_start_tag           3
+#define google_census_Metric_end_tag             4
+#define google_census_Resource_name_tag          1
+#define google_census_Resource_description_tag   2
+#define google_census_Resource_unit_tag          3
 #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_resource_name_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_count_tag      3
+
+#define google_census_Aggregation_distribution_tag 4
 
-#define google_census_Aggregation_interval_stats_tag 4
+#define google_census_Aggregation_interval_stats_tag 5
 #define google_census_Aggregation_name_tag       1
 #define google_census_Aggregation_description_tag 2
-#define google_census_Aggregation_tag_tag        5
+#define google_census_Aggregation_tag_tag        6
 
 /* 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_Resource_fields[4];
+extern const pb_field_t google_census_Resource_MeasurementUnit_fields[4];
+extern const pb_field_t google_census_AggregationDescriptor_fields[4];
 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];
@@ -268,13 +270,12 @@ 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];
+extern const pb_field_t google_census_Aggregation_fields[7];
+extern const pb_field_t google_census_Metric_fields[5];
 
 /* 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
diff --git a/src/core/ext/census/grpc_filter.c b/src/core/ext/census/grpc_filter.c
index f51d850e01..9dacc17eb4 100644
--- a/src/core/ext/census/grpc_filter.c
+++ b/src/core/ext/census/grpc_filter.c
@@ -127,38 +127,40 @@ static void server_start_transport_op(grpc_exec_ctx *exec_ctx,
   grpc_call_next_op(exec_ctx, elem, op);
 }
 
-static void client_init_call_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_call_element *elem,
-                                  grpc_call_element_args *args) {
+static grpc_error *client_init_call_elem(grpc_exec_ctx *exec_ctx,
+                                         grpc_call_element *elem,
+                                         grpc_call_element_args *args) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   memset(d, 0, sizeof(*d));
   d->start_ts = gpr_now(GPR_CLOCK_REALTIME);
+  return GRPC_ERROR_NONE;
 }
 
 static void client_destroy_call_elem(grpc_exec_ctx *exec_ctx,
                                      grpc_call_element *elem,
-                                     const grpc_call_stats *stats,
+                                     const grpc_call_final_info *final_info,
                                      void *ignored) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   /* TODO(hongyu): record rpc client stats and census_rpc_end_op here */
 }
 
-static void server_init_call_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_call_element *elem,
-                                  grpc_call_element_args *args) {
+static grpc_error *server_init_call_elem(grpc_exec_ctx *exec_ctx,
+                                         grpc_call_element *elem,
+                                         grpc_call_element_args *args) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   memset(d, 0, sizeof(*d));
   d->start_ts = gpr_now(GPR_CLOCK_REALTIME);
   /* TODO(hongyu): call census_tracing_start_op here. */
   grpc_closure_init(&d->finish_recv, server_on_done_recv, elem);
+  return GRPC_ERROR_NONE;
 }
 
 static void server_destroy_call_elem(grpc_exec_ctx *exec_ctx,
                                      grpc_call_element *elem,
-                                     const grpc_call_stats *stats,
+                                     const grpc_call_final_info *final_info,
                                      void *ignored) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
diff --git a/src/core/ext/census/initialize.c b/src/core/ext/census/initialize.c
index 896276e44a..55cbbe8e95 100644
--- a/src/core/ext/census/initialize.c
+++ b/src/core/ext/census/initialize.c
@@ -32,19 +32,31 @@
  */
 
 #include <grpc/census.h>
+#include "src/core/ext/census/base_resources.h"
+#include "src/core/ext/census/resource.h"
 
 static int features_enabled = CENSUS_FEATURE_NONE;
 
 int census_initialize(int features) {
   if (features_enabled != CENSUS_FEATURE_NONE) {
     // Must have been a previous call to census_initialize; return error
-    return 1;
+    return -1;
   }
-  features_enabled = features;
-  return 0;
+  features_enabled = features & CENSUS_FEATURE_ALL;
+  if (features & CENSUS_FEATURE_STATS) {
+    initialize_resources();
+    define_base_resources();
+  }
+
+  return features_enabled;
 }
 
-void census_shutdown(void) { features_enabled = CENSUS_FEATURE_NONE; }
+void census_shutdown(void) {
+  if (features_enabled & CENSUS_FEATURE_STATS) {
+    shutdown_resources();
+  }
+  features_enabled = CENSUS_FEATURE_NONE;
+}
 
 int census_supported(void) {
   /* TODO(aveitch): improve this as we implement features... */
diff --git a/src/core/ext/census/placeholders.c b/src/core/ext/census/placeholders.c
index fe23d13971..9f99c5bdcf 100644
--- a/src/core/ext/census/placeholders.c
+++ b/src/core/ext/census/placeholders.c
@@ -62,48 +62,3 @@ int census_trace_scan_start(int consume) {
   (void)consume;
   abort();
 }
-
-const census_aggregation *census_view_aggregrations(const census_view *view) {
-  (void)view;
-  abort();
-}
-
-census_view *census_view_create(uint32_t metric_id, const census_context *tags,
-                                const census_aggregation *aggregations,
-                                size_t naggregations) {
-  (void)metric_id;
-  (void)tags;
-  (void)aggregations;
-  (void)naggregations;
-  abort();
-}
-
-const census_context *census_view_tags(const census_view *view) {
-  (void)view;
-  abort();
-}
-
-void census_view_delete(census_view *view) {
-  (void)view;
-  abort();
-}
-
-const census_view_data *census_view_get_data(const census_view *view) {
-  (void)view;
-  abort();
-}
-
-size_t census_view_metric(const census_view *view) {
-  (void)view;
-  abort();
-}
-
-size_t census_view_naggregations(const census_view *view) {
-  (void)view;
-  abort();
-}
-
-void census_view_reset(census_view *view) {
-  (void)view;
-  abort();
-}
diff --git a/src/core/ext/census/resource.c b/src/core/ext/census/resource.c
new file mode 100644
index 0000000000..ed44f004f9
--- /dev/null
+++ b/src/core/ext/census/resource.c
@@ -0,0 +1,312 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include "src/core/ext/census/resource.h"
+#include "third_party/nanopb/pb_decode.h"
+
+#include <grpc/census.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/sync.h>
+
+#include <stdbool.h>
+#include <string.h>
+
+// Protect local resource data structures.
+static gpr_mu resource_lock;
+
+// Deleteing and creating resources are relatively rare events, and should not
+// be done in the critical path of performance sensitive code. We record
+// current resource id's used in a simple array, and just search it each time
+// we need to assign a new id, or look up a resource.
+static resource **resources = NULL;
+
+// Number of entries in *resources
+static size_t n_resources = 0;
+
+// Number of defined resources
+static size_t n_defined_resources = 0;
+
+void initialize_resources(void) {
+  gpr_mu_init(&resource_lock);
+  gpr_mu_lock(&resource_lock);
+  GPR_ASSERT(resources == NULL && n_resources == 0 && n_defined_resources == 0);
+  gpr_mu_unlock(&resource_lock);
+}
+
+// Delete a resource given it's ID. The ID must be a valid resource ID. Must be
+// called with resource_lock held.
+static void delete_resource_locked(size_t rid) {
+  GPR_ASSERT(resources[rid] != NULL);
+  gpr_free(resources[rid]->name);
+  gpr_free(resources[rid]->description);
+  gpr_free(resources[rid]->numerators);
+  gpr_free(resources[rid]->denominators);
+  gpr_free(resources[rid]);
+  resources[rid] = NULL;
+  n_defined_resources--;
+}
+
+void shutdown_resources(void) {
+  gpr_mu_lock(&resource_lock);
+  for (size_t i = 0; i < n_resources; i++) {
+    if (resources[i] != NULL) {
+      delete_resource_locked(i);
+    }
+  }
+  GPR_ASSERT(n_defined_resources == 0);
+  gpr_free(resources);
+  resources = NULL;
+  n_resources = 0;
+  gpr_mu_unlock(&resource_lock);
+}
+
+// Check the contents of string fields in a resource proto.
+static bool validate_string(pb_istream_t *stream, const pb_field_t *field,
+                            void **arg) {
+  resource *vresource = (resource *)*arg;
+  switch (field->tag) {
+    case google_census_Resource_name_tag:
+      // Name must have at least one character
+      if (stream->bytes_left == 0) {
+        gpr_log(GPR_INFO, "Zero-length Resource name.");
+        return false;
+      }
+      vresource->name = gpr_malloc(stream->bytes_left + 1);
+      vresource->name[stream->bytes_left] = '\0';
+      if (!pb_read(stream, (uint8_t *)vresource->name, stream->bytes_left)) {
+        return false;
+      }
+      // Can't have same name as an existing resource.
+      for (size_t i = 0; i < n_resources; i++) {
+        resource *compare = resources[i];
+        if (compare == vresource || compare == NULL) continue;
+        if (strcmp(compare->name, vresource->name) == 0) {
+          gpr_log(GPR_INFO, "Duplicate Resource name %s.", vresource->name);
+          return false;
+        }
+      }
+      break;
+    case google_census_Resource_description_tag:
+      if (stream->bytes_left == 0) {
+        return true;
+      }
+      vresource->description = gpr_malloc(stream->bytes_left + 1);
+      vresource->description[stream->bytes_left] = '\0';
+      if (!pb_read(stream, (uint8_t *)vresource->description,
+                   stream->bytes_left)) {
+        return false;
+      }
+      break;
+    default:
+      // No other string fields in Resource. Print warning and skip.
+      gpr_log(GPR_INFO, "Unknown string field type in Resource protobuf.");
+      if (!pb_read(stream, NULL, stream->bytes_left)) {
+        return false;
+      }
+      break;
+  }
+  return true;
+}
+
+// Decode numerators/denominators in a stream. The `count` and `bup`
+// (BasicUnit pointer) are pointers to the approriate fields in a resource
+// struct.
+static bool validate_units_helper(pb_istream_t *stream, int *count,
+                                  google_census_Resource_BasicUnit **bup) {
+  while (stream->bytes_left) {
+    (*count)++;
+    // Have to allocate a new array of values. Normal case is 0 or 1, so
+    // this should normally not be an issue.
+    google_census_Resource_BasicUnit *new_bup =
+        gpr_malloc((size_t)*count * sizeof(google_census_Resource_BasicUnit));
+    if (*count != 1) {
+      memcpy(new_bup, *bup,
+             (size_t)(*count - 1) * sizeof(google_census_Resource_BasicUnit));
+      gpr_free(*bup);
+    }
+    *bup = new_bup;
+    uint64_t value;
+    if (!pb_decode_varint(stream, &value)) {
+      return false;
+    }
+    *(*bup + *count - 1) = (google_census_Resource_BasicUnit)value;
+  }
+  return true;
+}
+
+// Validate units field of a Resource proto.
+static bool validate_units(pb_istream_t *stream, const pb_field_t *field,
+                           void **arg) {
+  resource *vresource = (resource *)(*arg);
+  switch (field->tag) {
+    case google_census_Resource_MeasurementUnit_numerator_tag:
+      return validate_units_helper(stream, &vresource->n_numerators,
+                                   &vresource->numerators);
+      break;
+    case google_census_Resource_MeasurementUnit_denominator_tag:
+      return validate_units_helper(stream, &vresource->n_denominators,
+                                   &vresource->denominators);
+      break;
+    default:
+      gpr_log(GPR_ERROR, "Unknown field type.");
+      return false;
+      break;
+  }
+  return true;
+}
+
+// Validate the contents of a Resource proto. `id` is the intended resource id.
+static bool validate_resource_pb(const uint8_t *resource_pb,
+                                 size_t resource_pb_size, size_t id) {
+  GPR_ASSERT(id < n_resources);
+  if (resource_pb == NULL) {
+    return false;
+  }
+  google_census_Resource vresource;
+  vresource.name.funcs.decode = &validate_string;
+  vresource.name.arg = resources[id];
+  vresource.description.funcs.decode = &validate_string;
+  vresource.description.arg = resources[id];
+  vresource.unit.numerator.funcs.decode = &validate_units;
+  vresource.unit.numerator.arg = resources[id];
+  vresource.unit.denominator.funcs.decode = &validate_units;
+  vresource.unit.denominator.arg = resources[id];
+
+  pb_istream_t stream =
+      pb_istream_from_buffer((uint8_t *)resource_pb, resource_pb_size);
+  if (!pb_decode(&stream, google_census_Resource_fields, &vresource)) {
+    return false;
+  }
+  // A Resource must have a name, a unit, with at least one numerator.
+  return (resources[id]->name != NULL && vresource.has_unit &&
+          resources[id]->n_numerators > 0);
+}
+
+// Allocate a blank resource, and return associated ID. Must be called with
+// resource_lock held.
+size_t allocate_resource(void) {
+  // use next_id to optimize expected placement of next new resource.
+  static size_t next_id = 0;
+  size_t id = n_resources;  // resource ID - initialize to invalid value.
+  // Expand resources if needed.
+  if (n_resources == n_defined_resources) {
+    size_t new_n_resources = n_resources ? n_resources * 2 : 2;
+    resource **new_resources = gpr_malloc(new_n_resources * sizeof(resource *));
+    memcpy(new_resources, resources, n_resources * sizeof(resource *));
+    memset(new_resources + n_resources, 0,
+           (new_n_resources - n_resources) * sizeof(resource *));
+    gpr_free(resources);
+    resources = new_resources;
+    n_resources = new_n_resources;
+    id = n_defined_resources;
+  } else {
+    GPR_ASSERT(n_defined_resources < n_resources);
+    // Find a free id.
+    for (size_t base = 0; base < n_resources; base++) {
+      id = (next_id + base) % n_resources;
+      if (resources[id] == NULL) break;
+    }
+  }
+  GPR_ASSERT(id < n_resources && resources[id] == NULL);
+  resources[id] = gpr_malloc(sizeof(resource));
+  memset(resources[id], 0, sizeof(resource));
+  n_defined_resources++;
+  next_id = (id + 1) % n_resources;
+  return id;
+}
+
+int32_t census_define_resource(const uint8_t *resource_pb,
+                               size_t resource_pb_size) {
+  if (resource_pb == NULL) {
+    return -1;
+  }
+  gpr_mu_lock(&resource_lock);
+  size_t id = allocate_resource();
+  // Validate pb, extract name.
+  if (!validate_resource_pb(resource_pb, resource_pb_size, id)) {
+    delete_resource_locked(id);
+    gpr_mu_unlock(&resource_lock);
+    return -1;
+  }
+  gpr_mu_unlock(&resource_lock);
+  return (int32_t)id;
+}
+
+void census_delete_resource(int32_t rid) {
+  gpr_mu_lock(&resource_lock);
+  if (rid >= 0 && (size_t)rid < n_resources && resources[rid] != NULL) {
+    delete_resource_locked((size_t)rid);
+  }
+  gpr_mu_unlock(&resource_lock);
+}
+
+int32_t census_resource_id(const char *name) {
+  gpr_mu_lock(&resource_lock);
+  for (int32_t id = 0; (size_t)id < n_resources; id++) {
+    if (resources[id] != NULL && strcmp(resources[id]->name, name) == 0) {
+      gpr_mu_unlock(&resource_lock);
+      return id;
+    }
+  }
+  gpr_mu_unlock(&resource_lock);
+  return -1;
+}
+
+int32_t define_resource(const resource *base) {
+  GPR_ASSERT(base != NULL && base->name != NULL && base->n_numerators > 0 &&
+             base->numerators != NULL);
+  gpr_mu_lock(&resource_lock);
+  size_t id = allocate_resource();
+  size_t len = strlen(base->name) + 1;
+  resources[id]->name = gpr_malloc(len);
+  memcpy(resources[id]->name, base->name, len);
+  if (base->description) {
+    len = strlen(base->description) + 1;
+    resources[id]->description = gpr_malloc(len);
+    memcpy(resources[id]->description, base->description, len);
+  }
+  resources[id]->prefix = base->prefix;
+  resources[id]->n_numerators = base->n_numerators;
+  len = (size_t)base->n_numerators * sizeof(*base->numerators);
+  resources[id]->numerators = gpr_malloc(len);
+  memcpy(resources[id]->numerators, base->numerators, len);
+  resources[id]->n_denominators = base->n_denominators;
+  if (base->n_denominators != 0) {
+    len = (size_t)base->n_denominators * sizeof(*base->denominators);
+    resources[id]->denominators = gpr_malloc(len);
+    memcpy(resources[id]->denominators, base->denominators, len);
+  }
+  gpr_mu_unlock(&resource_lock);
+  return (int32_t)id;
+}
diff --git a/src/core/ext/census/resource.h b/src/core/ext/census/resource.h
new file mode 100644
index 0000000000..591bff07da
--- /dev/null
+++ b/src/core/ext/census/resource.h
@@ -0,0 +1,63 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+/* Census-internal resource definition and manipluation functions. */
+#ifndef GRPC_CORE_EXT_CENSUS_RESOURCE_H
+#define GRPC_CORE_EXT_CENSUS_RESOURCE_H
+
+#include <grpc/grpc.h>
+#include "src/core/ext/census/gen/census.pb.h"
+
+/* Internal representation of a resource. */
+typedef struct {
+  char *name;
+  char *description;
+  int32_t prefix;
+  int n_numerators;
+  google_census_Resource_BasicUnit *numerators;
+  int n_denominators;
+  google_census_Resource_BasicUnit *denominators;
+} resource;
+
+/* Initialize and shutdown the resources subsystem. */
+void initialize_resources(void);
+void shutdown_resources(void);
+
+/* Add a new resource, given a proposed resource structure. Returns the
+   resource ID, or -ve on failure.
+   TODO(aveitch): this function exists to support addition of the base
+   resources. It should be removed when we have the ability to add resources
+   from configuration files. */
+int32_t define_resource(const resource *base);
+
+#endif /* GRPC_CORE_EXT_CENSUS_RESOURCE_H */