[SPARK-4000][BUILD] Sends archived unit tests logs to Jenkins master

This PR sends archived unit tests logs to the build history directory in Jenkins master, so that we can serve it via HTTP later to help debugging Jenkins build failures.

pwendell JoshRosen Please help review, thanks!

Author: Cheng Lian <lian@databricks.com>

Closes #2845 from liancheng/log-archive and squashes the following commits:

ac8d9d4 [Cheng Lian] Includes build number in messages posted to GitHub
68c7010 [Cheng Lian] Logs backup should be implemented in dev/run-tests-jenkins
4b912f7 [Cheng Lian] Sends archived unit tests logs to Jenkins master

dev/run-tests-jenkins

@@ -53,9 +53,9 @@ function post_message () {
   local message=$1
   local data="{\"body\": \"$message\"}"
   local HTTP_CODE_HEADER="HTTP Response Code: "
-  
+
   echo "Attempting to post to Github..."
-  
+
   local curl_output=$(
     curl `#--dump-header -` \
       --silent \
@@ -75,12 +75,12 @@ function post_message () {
       echo " > data: ${data}" >&2
       # exit $curl_status
   fi
-  
+
   local api_response=$(
     echo "${curl_output}" \
     | grep -v -e "^${HTTP_CODE_HEADER}"
   )
-  
+
   local http_code=$(
     echo "${curl_output}" \
     | grep -e "^${HTTP_CODE_HEADER}" \
@@ -92,12 +92,39 @@ function post_message () {
       echo " > api_response: ${api_response}" >&2
       echo " > data: ${data}" >&2
   fi
-  
+
   if [ "$curl_status" -eq 0 ] && [ "$http_code" -eq "201" ]; then
     echo " > Post successful."
   fi
 }
 
+function send_archived_logs () {
+  echo "Archiving unit tests logs..."
+
+  local log_files=$(find . -name "unit-tests.log")
+
+  if [ -z "$log_files" ]; then
+    echo "> No log files found." >&2
+  else
+    local log_archive="unit-tests-logs.tar.gz"
+    echo "$log_files" | xargs tar czf ${log_archive}
+
+    local jenkins_build_dir=${JENKINS_HOME}/jobs/${JOB_NAME}/builds/${BUILD_NUMBER}
+    local scp_output=$(scp ${log_archive} amp-jenkins-master:${jenkins_build_dir}/${log_archive})
+    local scp_status="$?"
+
+    if [ "$scp_status" -ne 0 ]; then
+      echo "Failed to send archived unit tests logs to Jenkins master." >&2
+      echo "> scp_status: ${scp_status}" >&2
+      echo "> scp_output: ${scp_output}" >&2
+    else
+      echo "> Send successful."
+    fi
+
+    rm -f ${log_archive}
+  fi
+}
+
 
 # We diff master...$ghprbActualCommit because that gets us changes introduced in the PR
 #+ and not anything else added to master since the PR was branched.
@@ -109,7 +136,7 @@ function post_message () {
   else
     merge_note=" * This patch merges cleanly."
   fi
-  
+
   source_files=$(
       git diff master...$ghprbActualCommit --name-only  `# diff patch against master from branch point` \
     | grep -v -e "\/test"                               `# ignore files in test directories` \
@@ -144,12 +171,12 @@ function post_message () {
 # post start message
 {
   start_message="\
-  [QA tests have started](${BUILD_URL}consoleFull) for \
+  [Test build ${BUILD_DISPLAY_NAME} has started](${BUILD_URL}consoleFull) for \
   PR $ghprbPullId at commit [\`${SHORT_COMMIT_HASH}\`](${COMMIT_URL})."
-  
+
   start_message="${start_message}\n${merge_note}"
   # start_message="${start_message}\n${public_classes_note}"
-  
+
   post_message "$start_message"
 }
 
@@ -159,7 +186,7 @@ function post_message () {
   test_result="$?"
 
   if [ "$test_result" -eq "124" ]; then
-    fail_message="**[Tests timed out](${BUILD_URL}consoleFull)** \
+    fail_message="**[Test build ${BUILD_DISPLAY_NAME} timed out](${BUILD_URL}consoleFull)** \
     for PR $ghprbPullId at commit [\`${SHORT_COMMIT_HASH}\`](${COMMIT_URL}) \
     after a configured wait of \`${TESTS_TIMEOUT}\`."
 
@@ -187,15 +214,17 @@ function post_message () {
     else
       failing_test="some tests"
     fi
-    
+
     test_result_note=" * This patch **fails $failing_test**."
   fi
+
+  send_archived_logs
 }
 
 # post end message
 {
   result_message="\
-  [QA tests have finished](${BUILD_URL}consoleFull) for \
+  [Test build ${BUILD_DISPLAY_NAME} has finished](${BUILD_URL}consoleFull) for \
   PR $ghprbPullId at commit [\`${SHORT_COMMIT_HASH}\`](${COMMIT_URL})."
 
   result_message="${result_message}\n${test_result_note}"