Sync GitHub comment edits to Slack

[jbingham17]

Summary

• Triggers workflow on edited comment events (in addition to created)
• Tags each Slack message with the GitHub comment ID via Slack message metadata
• On edit, finds the matching Slack message in the thread using conversations.replies + metadata lookup, then updates it via chat.update
• Falls back to posting a new message if the original can't be found

Test plan

• Comment on this PR, then edit the comment — the Slack thread reply should update in place
• Verify new comments still post correctly as thread replies

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features

  • Slack notifications now support edited comments and will update the corresponding Slack message when possible.
  • Edited comments fall back to posting a new reply if the original message can't be located.

• Improvements

  • Richer, cleaner message formatting with a concise header and truncated preview for long comments.
  • Better comment cleaning (removes extraneous markup) and stronger thread discovery for more accurate linking.

[coderabbitai]

Caution

Review failed

The pull request is closed.

Walkthrough

The workflow .github/workflows/pr-comment-slack-notify.yml was expanded to handle both created and edited issue and review comments. Two new public inputs, EVENT_ACTION and COMMENT_ID, distinguish event type and identify the comment. Comment text is preprocessed and truncated; Slack message blocks (COMMENT_BLOCKS, header) and METADATA (including comment_id) are dynamically built. If EVENT_ACTION is edited and a thread exists, the workflow searches thread replies for matching metadata.comment_id and updates the Slack message with chat.update; otherwise it posts a new top-level message or thread reply. All Slack API calls now send blocks and metadata.

Possibly related PRs

• Sync GitHub comment edits to Slack #4 — Modifies the same workflow to add EVENT_ACTION and COMMENT_ID, build COMMENT_BLOCKS and METADATA, and implement edit-handling that finds and updates Slack messages via conversations.replies plus chat.update.

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[jbingham17]

Sizurp

[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In @.github/workflows/pr-comment-slack-notify.yml:
- Around line 162-170: The current conversations.replies call that sets REPLIES
and extracts SLACK_MSG_TS can miss the edited message in long threads due to the
200-item cap; update the logic that runs when THREAD_TS is set (the edited
branch) to perform cursor-based pagination: repeatedly call
conversations.replies with the response_metadata.next_cursor until either the
message matching COMMENT_ID is found or no cursor remains, merging/fetching each
page into REPLIES or scanning per-page for the matching
.metadata.event_payload.comment_id to set SLACK_MSG_TS; ensure the cursor query
parameter is URL-encoded when appended to the API URL and stop the loop once
SLACK_MSG_TS is determined or next_cursor is empty to avoid infinite loops.

[coderabbitai]

⚠️ Potential issue | 🟠 Major

🧩 Analysis chain

🌐 Web query:

Slack conversations.replies API pagination next_cursor limit

💡 Result:

conversations.replies uses cursor-based pagination:

• First request: pass channel, ts, and optionally limit (page size). Example: limit=200 (Slack recommends ≤200). The method’s general maximum is documented as 1000, but see the non‑Marketplace note below. [1][2]
• Next pages: read response_metadata.next_cursor from the response, then call again with cursor=<next_cursor> (and the same limit). Repeat until next_cursor is missing/null/empty string (""). [1][3]
• Don’t stop just because you got fewer than limit items—Slack may return fewer (even 0) while still providing a next_cursor. Always key off next_cursor. [2][3]
• Encoding: cursor strings often end with =; when sending as a URL query parameter, encode it (e.g., = → %3D). [3]

Important (rate-limit-driven limit change): For apps commercially distributed outside the Slack Marketplace, Slack reduced the default and maximum limit for conversations.replies to 15 and rate-limited the method to 1 request/min for certain apps/installations (see Slack’s changelog and method docs for applicability dates). [1][4]

Minimal pagination loop (pseudo):

1. cursor = null
2. call conversations.replies(channel, ts, limit, cursor?)
3. cursor = response.response_metadata.next_cursor
4. if cursor is empty → done; else repeat. [1][3]

Sources:
[1] Slack method docs: conversations.replies https://api.slack.com/methods/conversations.replies
[2] Slack Conversations API pagination notes https://api.slack.com/conversations-api
[3] Slack pagination guide https://docs.slack.dev/apis/web-api/pagination/
[4] Slack changelog (rate limit + limit=15 for non‑Marketplace) https://api.slack.com/changelog/2025-05-terms-rate-limit-update-and-faq

---

Paginate replies to avoid missing edited messages in long threads.
conversations.replies is capped at 200 (or 15 for non-Marketplace apps); if a thread exceeds that, the target message won't be found and edits will post a duplicate reply instead of updating in place. Implement cursor-based pagination using response_metadata.next_cursor.

One detail: URL-encode the cursor when passing it as a query parameter (e.g., = → %3D), since cursor strings often contain special characters.

🧭 Suggested pagination pattern

- REPLIES=$(curl -s "https://slack.com/api/conversations.replies?channel=$SLACK_CHANNEL_ID&ts=$THREAD_TS&include_all_metadata=true&limit=200" \
-   -H "Authorization: Bearer $SLACK_BOT_TOKEN")
-
- SLACK_MSG_TS=$(echo "$REPLIES" | jq -r --arg cid "$COMMENT_ID" '
-   .messages[]
-   | select(.metadata.event_payload.comment_id == $cid)
-   | .ts' | head -1)
+ SLACK_MSG_TS=""
+ CURSOR=""
+ while :; do
+   REPLIES=$(curl -s "https://slack.com/api/conversations.replies?channel=$SLACK_CHANNEL_ID&ts=$THREAD_TS&include_all_metadata=true&limit=200&cursor=$CURSOR" \
+     -H "Authorization: Bearer $SLACK_BOT_TOKEN")
+
+   SLACK_MSG_TS=$(echo "$REPLIES" | jq -r --arg cid "$COMMENT_ID" '
+     .messages[]
+     | select(.metadata.event_payload.comment_id == $cid)
+     | .ts' | head -1)
+
+   if [ -n "$SLACK_MSG_TS" ] && [ "$SLACK_MSG_TS" != "null" ]; then
+     break
+   fi
+
+   CURSOR=$(echo "$REPLIES" | jq -r '.response_metadata.next_cursor // empty')
+   [ -z "$CURSOR" ] && break
+ done

Note: Consider URL-encoding the cursor parameter if special characters cause issues.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In @.github/workflows/pr-comment-slack-notify.yml around lines 162 - 170, The
current conversations.replies call that sets REPLIES and extracts SLACK_MSG_TS
can miss the edited message in long threads due to the 200-item cap; update the
logic that runs when THREAD_TS is set (the edited branch) to perform
cursor-based pagination: repeatedly call conversations.replies with the
response_metadata.next_cursor until either the message matching COMMENT_ID is
found or no cursor remains, merging/fetching each page into REPLIES or scanning
per-page for the matching .metadata.event_payload.comment_id to set
SLACK_MSG_TS; ensure the cursor query parameter is URL-encoded when appended to
the API URL and stop the loop once SLACK_MSG_TS is determined or next_cursor is
empty to avoid infinite loops.