add slack notifications for cherry-pick (#7423)

.circleci/scripts/cherry-picker.sh

@@ -6,28 +6,85 @@
 # Requires $CIRCLE_PROJECT_USERNAME, $CIRCLE_PROJECT_REPONAME, and $CIRCLE_SHA1 from CircleCI
 #!/bin/bash
 
+# colorized status prompt
+function status {
+    tput setaf 4
+    echo "$@"
+    tput sgr0
+}
+
+# This function will do the cherry-picking of a commit on a branch
+# Exit 1 if cherry-picking fails
+function cherry_pick_with_slack_notification {
+    # Arguments:
+    #   $1 - branch to cherry-pick to
+    #   $2 - commit to cherry-pick
+    #   $3 - url to PR of commit
+
+    local branch=$1
+    local commit=$2
+    local pr_url=$3
+
+    git checkout $branch || exit 1
+    # If git cherry-pick fails, we send a failure notification
+    if ! git cherry-pick $commit; then
+        status "🍒❌ Cherry pick of commit ${commit:0:7} from $pr_url onto $branch failed!"
+        curl -X POST -H 'Content-type: application/json' \
+        --data \
+        "{ \
+        \"attachments\": [ \
+            { \
+            \"fallback\": \"Cherry pick failed!\", \
+            \"text\": \"🍒❌ Cherry picking of <$pr_url|${commit:0:7}> to \`$branch\` failed!\n\nBuild Log: ${CIRCLE_BUILD_URL}\", \
+            \"footer\": \"${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}\", \
+            \"ts\": \"$(date +%s)\", \
+            \"color\": \"danger\" \
+            } \
+        ] \
+        }" ${CONSUL_SLACK_WEBHOOK_URL}
+        git status
+        exit 1
+    # Else we send a success notification
+    else
+        status "🍒✅ Cherry picking of PR commit ${commit:0:7} from $pr_url succeeded!"
+        curl -X POST -H 'Content-type: application/json' \
+        --data \
+        "{ \
+        \"attachments\": [ \
+            { \
+            \"fallback\": \"Cherry pick succeeded!\", \
+            \"text\": \"🍒✅ Cherry picking of <$pr_url|${commit:0:7}> to \`$branch\` succeeded!\n\nBuild Log: ${CIRCLE_BUILD_URL}\", \
+            \"footer\": \"${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}\", \
+            \"ts\": \"$(date +%s)\", \
+            \"color\": \"good\" \
+            } \
+        ] \
+        }" ${CONSUL_SLACK_WEBHOOK_URL}
+    fi
+}
+
 # search for the PR labels applicable to the specified commit
 resp=$(curl -f -s "https://api.github.com/search/issues?q=repo:$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME+sha:$CIRCLE_SHA1")
-status="$?"
-if [[ "$status" -ne 0 ]]; then
-  echo "The GitHub API returned $status which means it was probably rate limited."
-  exit $status
+ret="$?"
+if [[ "$ret" -ne 0 ]]; then
+    status "The GitHub API returned $ret which means it was probably rate limited."
+    exit $ret
 fi
 
 # get the count from the GitHub API to check if the commit matched a PR
 count=$(echo "$resp" | jq '.total_count')
 if [[ "$count" -eq 0 ]]; then
-  echo "This commit was not associated with a PR"
+    status "This commit was not associated with a PR"
     exit 0
 fi
 
 # If the API returned a non-zero count, we have found a PR with that commit so we find
 # the labels from the PR
 labels=$(echo "$resp" | jq --raw-output '.items[].labels[] | .name')
-status="$?"
-if [[ "$status" -ne 0 ]]; then
-  pr_url=$(echo "$resp" | jq --raw-output '.items[].pull_request.url')
-  echo "jq exited with $status when trying to find label names. Are there labels applied to the PR ($pr_url)?"
+ret="$?"
+if [[ "$ret" -ne 0 ]]; then
+    pr_url=$(echo "$resp" | jq --raw-output '.items[].pull_request.html_url')
+    status "jq exited with $ret when trying to find label names. Are there labels applied to the PR ($pr_url)?"
     # This can be a valid error but usually this means we do not have any labels so it doesn't signal
     # cherry-picking is possible. Exit 0 for now unless we run into cases where these failures are important.
     exit 0
@@ -37,19 +94,18 @@ fi
 for label in $labels; do
     git config --local user.email "hashicorp-ci@users.noreply.github.com"
     git config --local user.name "hashicorp-ci"
-    echo "checking label: $label"
+    status "checking label: $label"
     # if the label matches docs*, it will attempt to cherry-pick to stable-website
     if [[ $label =~ docs* ]]; then
-        echo "docs"
-        git checkout stable-website || exit 1
-        git cherry-pick $CIRCLE_SHA1 || exit 1
+        status "backporting to stable-website"
+        branch="stable-website"
+        cherry_pick_with_slack_notification $branch $CIRCLE_SHA1 $pr_url
         git push origin stable-website
     # else if the label matches backport/*, it will attempt to cherry-pick to the release branch
     elif [[ $label =~ backport/* ]]; then
-        echo "backporting to $label"
+        status "backporting to $label"
         branch="${label/backport/release}.x"
-        git checkout $branch || exit 1
-        git cherry-pick $CIRCLE_SHA1 || exit 1
+        cherry_pick_with_slack_notification $branch $CIRCLE_SHA1 $pr_url
         git push origin $branch
     fi
 done