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Update PR comments

Update PR comments #10

Workflow file for this run

name: Update PR comments
on:
# This number should correspond to the IGNORE_RUNS_OLDER_THAN value below.
# When setting up for the first time, use "on: push" instead of "on: schedule"
# and set IGNORE_RUNS_OLDER_THAN to a very high number until it runs once.
workflow_run:
workflows:
- Node CI for Boostlet
types:
- completed
jobs:
pr_updater:
runs-on: ubuntu-latest
steps:
- name: main
env:
GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
WORKFLOW_NAME: "Node CI for Boostlet"
# the name of the artifact whose content comment published by PR. Must have a single markdown file inside.
MSG_ARTIFACT_NAME: "pr_message"
# How far back to look for finished runs, in minutes.
# Set to 10-20 minutes higher than cron's job frequency set above.
IGNORE_RUNS_OLDER_THAN: 30
# How far back to look for updated pull requests, in minutes.
# Should be bigger than IGNORE_RUNS_OLDER_THAN by the maximum time a pull request jobs may take
IGNORE_PRS_OLDER_THAN: 80
run: |
#
# Strategy:
# * get all recently updated pull requests
# * get all recent workflow runs
# * match pull requests and their current SHA with the last workflow run for the same SHA
# * for each found match of <pull-request-number> and <workflow-run-id> :
# * download artifact from the workflow run -- expects a single file with markdown content
# * look through existing PR comments to see if we have posted a comment before
# (uses a hidden magical header to identify our comment)
# * either create or update the comment with the new text (if changed)
#
export GITHUB_API="https://api.github.com/repos/$GITHUB_REPOSITORY"
export COMMENT_MAGIC_HEADER='<!--'" Do not edit. This comment will be auto-updated with artifact '$MSG_ARTIFACT_NAME' created by action '$WORKFLOW_NAME' -->"
# A useful wrapper around CURL
crl() {
curl --silent --show-error --location --retry 1 "${@:2}" \
-H "Accept: application/vnd.github.antiope-preview+json, application/vnd.github.v3+json" \
"$1"
}
auth_crl() {
crl "$1" -H "authorization: Bearer $GITHUB_TOKEN" "${@:2}"
}
#
# Parse current pull requests
#
# Get all pull requests, most recently updated first
# (this way we don't need to page through all of them)
# Filter out PRs that are older than $IGNORE_PRS_OLDER_THAN minutes
# Result is an object, mapping a "key" to the pull request number:
# {
# "nyurik/openmaptiles/nyurik-patch-1/4953dd2370b9988a7832d090b5e47b3cd867f594": 6,
# ...
# }
PULL_REQUESTS_RAW="$( crl "$GITHUB_API/pulls?sort=updated&direction=desc" )"
if ! PULL_REQUESTS="$(jq --arg IGNORE_PRS_OLDER_THAN "$IGNORE_PRS_OLDER_THAN" '
map(
# Only select unlocked pull requests updated within last $IGNORE_PRS_OLDER_THAN minutes
select(.locked==false
and (now - (.updated_at|fromdate)) / 60 < ($IGNORE_PRS_OLDER_THAN | tonumber))
# Prepare for "from_entries" by creating a key/value object
# The key is a combination of repository name, branch name, and latest SHA
| { key: (.head.repo.full_name + "/" + .head.ref + "/" + .head.sha), value: .number }
)
| from_entries
' <( echo "$PULL_REQUESTS_RAW" ) )"; then
echo "Error parsing pull requests"
echo "$PULL_REQUESTS_RAW"
exit 1
fi
# Count how many pull requests we should process, and exit early if there are none
PR_COUNT="$(jq 'length' <( echo "$PULL_REQUESTS" ) )"
if [ "$PR_COUNT" -eq 0 ]; then
echo "There are no pull requests updated in the last $IGNORE_PRS_OLDER_THAN minutes. Exiting."
exit
else
echo "$PR_COUNT pull requests have been updated in the last $IGNORE_PRS_OLDER_THAN minutes"
echo "$PULL_REQUESTS" | jq -r 'keys|.[]|" * " + .'
fi
#
# Resolve workflow name into workflow ID
#
WORKFLOW_ID="$(crl "$GITHUB_API/actions/workflows" \
| jq --arg WORKFLOW_NAME "$WORKFLOW_NAME" '
.workflows[] | select(.name == $WORKFLOW_NAME) | .id
')"
if [ -z "$WORKFLOW_ID" ]; then
echo "Unable to find workflow '$WORKFLOW_NAME' in $GITHUB_REPOSITORY"
exit 1
else
echo "Resolved workflow '$WORKFLOW_NAME' to ID $WORKFLOW_ID"
fi
#
# Match pull requests with the workflow runs
#
# Get all workflow runs that were triggered by pull requests
WORKFLOW_PR_RUNS="$(crl "$GITHUB_API/actions/workflows/${WORKFLOW_ID}/runs?event=pull_request")"
# For each workflow run, match it with the pull request to get the PR number
# A match is based on "source repository + branch + SHA" key
# In rare cases (e.g. force push to an older revision), there could be more than one match
# for a given PR number, so just use the most recent one.
# Result is a table (list of lists) - each row with PR number, JOB ID, and the above key
PR_JOB_MAP="$(jq --arg IGNORE_RUNS_OLDER_THAN "$IGNORE_RUNS_OLDER_THAN" '
# second input is the pull request map - use it to lookup PR numbers
input as $PULL_REQUESTS
| .workflow_runs
| map(
# Create a new object with the relevant values
{
id,
updated_at,
# create lookup key based on source repository + branch + SHA
key: (.head_repository.full_name + "/" + .head_branch + "/" + .head_sha),
# was this a successful run?
# do not include .conclusion=="success" because errors could also post messages
success: (.status=="completed")
}
# lookup PR number from $PULL_REQUESTS using the above key
| . += { pr_number: $PULL_REQUESTS[.key] }
# Remove runs that were not in the list of the PRs
| select(.pr_number)
)
# Keep just the most recent run per pull request
| group_by(.pr_number)
| map(
sort_by(.updated_at)
| last
# If the most recent run did not succeed, or if the run is too old, ignore it
| select(.success and (now - (.updated_at|fromdate)) / 60 < ($IGNORE_RUNS_OLDER_THAN | tonumber))
# Keep just the pull request number mapping to run ID
| { pr_number, id, key }
)
' <( echo "$WORKFLOW_PR_RUNS" ) <( echo "$PULL_REQUESTS" ) )"
# Count how many jobs we should process, and exit early if there are none
JOBS_COUNT="$(jq 'length' <( echo "$PR_JOB_MAP" ) )"
if [ "$JOBS_COUNT" -eq 0 ]; then
echo "There are no recent workflow job runs in the last $IGNORE_RUNS_OLDER_THAN minutes. Exiting."
exit
else
echo "$JOBS_COUNT '$WORKFLOW_NAME' jobs have been updated in the last $IGNORE_RUNS_OLDER_THAN minutes"
echo "$PR_JOB_MAP" | jq -r '.[] | " * PR #\(.pr_number) Job #\(.id) -- \(.key) "'
fi
#
# Iterate over the found pairs of PR number + run ID, and update them all
#
echo "$PR_JOB_MAP" | jq -r '.[] | [ .pr_number, .id, .key ] | @sh' | \
while read -r PR_NUMBER RUN_ID RUN_KEY; do
echo "Processing '$WORKFLOW_NAME' run #$RUN_ID for pull request #$PR_NUMBER $RUN_KEY..."
ARTIFACTS="$(crl "$GITHUB_API/actions/runs/$RUN_ID/artifacts")"
# Find the artifact download URL for the artifact with the expected name
ARTIFACT_URL="$(jq -r --arg MSG_ARTIFACT_NAME "$MSG_ARTIFACT_NAME" '
.artifacts
| map(select(.name == $MSG_ARTIFACT_NAME and .expired == false))
| first
| .archive_download_url
| select(.!=null)
' <( echo "$ARTIFACTS" ) )"
if [ -z "$ARTIFACT_URL" ]; then
echo "Unable to find an artifact named '$MSG_ARTIFACT_NAME' in workflow $RUN_ID (PR #$PR_NUMBER), skipping..."
continue
fi
echo "Downloading artifact $ARTIFACT_URL (assuming single text file per artifact)..."
if ! MESSAGE="$(auth_crl "$ARTIFACT_URL" | gunzip)"; then
echo "Unable to download or parse message from artifact '$MSG_ARTIFACT_NAME' in workflow $RUN_ID (PR #$PR_NUMBER), skipping..."
continue
fi
if [ -z "$MESSAGE" ]; then
echo "Empty message in artifact '$MSG_ARTIFACT_NAME' in workflow $RUN_ID (PR #$PR_NUMBER), skipping..."
continue
fi
# Create a message body by appending a magic header
# and stripping any starting and ending whitespace from the original message
MESSAGE_BODY="$(jq -n \
--arg COMMENT_MAGIC_HEADER "$COMMENT_MAGIC_HEADER" \
--arg MESSAGE "$MESSAGE" \
'{ body: ($COMMENT_MAGIC_HEADER + "\n" + ($MESSAGE | sub( "^[\\s\\p{Cc}]+"; "" ) | sub( "[\\s\\p{Cc}]+$"; "" ))) }' \
)"
EXISTING_PR_COMMENTS="$(crl "$GITHUB_API/issues/$PR_NUMBER/comments")"
# Get the comment URL for the first comment that begins with the magic header, or empty string
OLD_COMMENT="$(jq --arg COMMENT_MAGIC_HEADER "$COMMENT_MAGIC_HEADER" '
map(select(.body | startswith($COMMENT_MAGIC_HEADER)))
| first
| select(.!=null)
' <( echo "$EXISTING_PR_COMMENTS" ) )"
if [ -z "$OLD_COMMENT" ]; then
COMMENT_HTML_URL="$(auth_crl "$GITHUB_API/issues/$PR_NUMBER/comments" \
-X POST \
-H "Content-Type: application/json" \
--data "$MESSAGE_BODY" \
| jq -r '.html_url' )"
COMMENT_INFO="New comment $COMMENT_HTML_URL was created"
else
# Make sure the content of the message has changed
COMMENT_URL="$(jq -r '
(input | .body) as $body
| select(.body | . != $body)
| .url
' <( echo "$OLD_COMMENT" ) <( echo "$MESSAGE_BODY" ) )"
if [ -z "$COMMENT_URL" ]; then
echo "The message has already been posted from artifact '$MSG_ARTIFACT_NAME' in workflow $RUN_ID (PR #$PR_NUMBER), skipping..."
continue
fi
COMMENT_HTML_URL="$(auth_crl "$COMMENT_URL" \
-X PATCH \
-H "Content-Type: application/json" \
--data "$MESSAGE_BODY" \
| jq -r '.html_url' )"
COMMENT_INFO="Existing comment $COMMENT_HTML_URL was updated"
fi
echo "$COMMENT_INFO from workflow $WORKFLOW_NAME #$RUN_ID"
done