buildscripts: Add Kokoro-based CI for Android APK stats

buildscripts/kokoro/cronet.sh

@@ -3,6 +3,118 @@
 set -exu -o pipefail
 cat /VERSION
 
-cd ./github/grpc-java/cronet
+BASE_DIR="$(pwd)"
+
+# Build Cronet
+
+cd "$BASE_DIR/github/grpc-java/cronet"
 ./cronet_deps.sh
 ../gradlew --include-build .. build
+
+
+# Install gRPC and codegen for the Android examples
+# (a composite gradle build can't find protoc-gen-grpc-java)
+
+cd "$BASE_DIR/github/grpc-java"
+
+export GRADLE_OPTS=-Xmx512m
+export PROTOBUF_VERSION=3.5.1
+export LDFLAGS=-L/tmp/protobuf/lib
+export CXXFLAGS=-I/tmp/protobuf/include
+export LD_LIBRARY_PATH=/tmp/protobuf/lib
+export OS_NAME=$(uname)
+
+# Proto deps
+buildscripts/make_dependencies.sh
+ln -s "/tmp/protobuf-${PROTOBUF_VERSION}/$(uname -s)-$(uname -p)" /tmp/protobuf
+
+./gradlew install
+
+cd ./examples/android/clientcache
+./gradlew build
+cd ../routeguide
+./gradlew build
+cd ../helloworld
+./gradlew build
+
+
+# Skip APK size and dex count comparisons for non-PR builds
+
+if [[ -z "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" ]]; then
+    echo "Skipping APK size and dex count"
+    exit 0
+fi
+
+
+# Set up APK size and dex count statuses
+
+SET_GITHUB_STATUS="$TMPDIR/set_github_status.py"
+cp "$BASE_DIR/github/grpc-java/buildscripts/set_github_status.py" "$SET_GITHUB_STATUS"
+
+gsutil cp gs://grpc-testing-secrets/github_credentials/oauth_token.txt ~/
+
+function set_status_to_fail_on_error {
+  "$SET_GITHUB_STATUS" \
+    --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+    --state error \
+    --description "Failed to calculate DEX count" \
+    --context android/dex_diff --oauth_file ~/oauth_token.txt
+  "$SET_GITHUB_STATUS" \
+    --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+    --state error \
+    --description "Failed to calculate APK size" \
+    --context android/apk_diff --oauth_file ~/oauth_token.txt
+}
+trap set_status_to_fail_on_error ERR
+
+
+"$SET_GITHUB_STATUS" \
+  --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+  --state pending \
+  --description "Waiting for DEX count to be reported" \
+  --context android/dex_diff --oauth_file ~/oauth_token.txt
+"$SET_GITHUB_STATUS" \
+  --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+  --state pending \
+  --description "Waiting for APK size to be reported" \
+  --context android/apk_diff --oauth_file ~/oauth_token.txt
+
+# Collect APK size and dex count stats for the helloworld example
+
+read -r ignored new_dex_count < \
+  <("${ANDROID_HOME}/tools/bin/apkanalyzer" dex references app/build/outputs/apk/release/app-release-unsigned.apk)
+
+new_apk_size="$(stat --printf=%s app/build/outputs/apk/release/app-release-unsigned.apk)"
+
+
+# Get the APK size and dex count stats using the pull request base commit
+
+cd $BASE_DIR/github/grpc-java
+git checkout HEAD^
+./gradlew install
+cd examples/android/helloworld/
+./gradlew build
+
+read -r ignored old_dex_count < \
+  <("${ANDROID_HOME}/tools/bin/apkanalyzer" dex references app/build/outputs/apk/release/app-release-unsigned.apk)
+
+old_apk_size="$(stat --printf=%s app/build/outputs/apk/release/app-release-unsigned.apk)"
+
+dex_count_delta="$((new_dex_count-old_dex_count))"
+
+apk_size_delta="$((new_apk_size-old_apk_size))"
+
+
+# Update the statuses with the deltas
+
+"$SET_GITHUB_STATUS" \
+  --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+  --state success \
+  --description "New DEX reference count: $(printf "%'d" "$new_dex_count") (delta: $(printf "%'d" "$dex_count_delta"))" \
+  --context android/dex_diff --oauth_file ~/oauth_token.txt
+
+"$SET_GITHUB_STATUS" \
+  --sha1 "$KOKORO_GITHUB_PULL_REQUEST_COMMIT" \
+  --state success \
+  --description "New APK size in bytes: $(printf "%'d" "$new_apk_size") (delta: $(printf "%'d" "$apk_size_delta"))" \
+  --context android/apk_diff --oauth_file ~/oauth_token.txt

buildscripts/set_github_status.py

@@ -0,0 +1,64 @@
+#!/usr/bin/env python2.7
+#
+# Copyright 2018 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import argparse
+import json
+import urllib2
+
+
+def run():
+  argp = argparse.ArgumentParser(description='Set status on pull request')
+
+  argp.add_argument(
+      '--sha1', type=str, help='SHA1 of the commit', required=True)
+  argp.add_argument(
+      '--state',
+      type=str,
+      choices=('error', 'failure', 'pending', 'success'),
+      help='State to set',
+      required=True)
+  argp.add_argument(
+      '--description', type=str, help='Status description', required=True)
+  argp.add_argument('--context', type=str, help='Status context', required=True)
+  argp.add_argument(
+      '--oauth_file', type=str, help='File with OAuth token', required=True)
+
+  args = argp.parse_args()
+  sha1 = args.sha1
+  state = args.state
+  description = args.description
+  context = args.context
+  oauth_file = args.oauth_file
+
+  with open(oauth_file, 'r') as oauth_file_reader:
+    oauth_token = oauth_file_reader.read().replace('\n', '')
+
+  req = urllib2.Request(
+      url='https://api.github.com/repos/grpc/grpc-java/statuses/%s' % sha1,
+      data=json.dumps({
+          'state': state,
+          'description': description,
+          'context': context,
+      }),
+      headers={
+          'Authorization': 'token %s' % oauth_token,
+          'Content-Type': 'application/json',
+      })
+  print urllib2.urlopen(req).read()
+
+
+if __name__ == '__main__':
+  run()