Merge pull request #2 from ynab/db/reply-in-thread-support

add ts output + support for sending threaded replies when posting

README.md

@@ -12,10 +12,20 @@ GitHub Action that posts a message to a Slack channel
 
 **Required** The channel name to post to (example: `#general`)
 
+#### `thread_ts`
+
+**Optional** The timestamp ID of the parent message to reply to (e.g., the `ts` output from a previous Slack message call)
+
 ### `text`
 
 **Required** The message text to post
 
+## Outputs
+
+### `ts`
+
+The timestamp ID of the message (can be used to make subsequent Slack messages a threaded reply)
+
 ## Example usage
 
 ```yaml

action.yml

@@ -6,17 +6,28 @@ inputs:
     required: false
   channel:
     description: "The channel name to post to"
-    required: true    
+    required: true
+  thread_ts:
+    description: "The timestamp ID of the parent message to reply to"
+    required: false
   text:
     description: "The message text to post"
     required: true
+outputs:
+  ts:
+    description: "The timestamp ID of the message that was just posted"
 branding:
   icon: 'tag'
   color: 'blue'
 runs:
   using: 'composite'
   steps:
     - run: |
-        curl --silent --show-error -X POST -H "Authorization: Bearer ${{ env.SLACK_BOT_TOKEN || inputs.token }}" -H "Content-Type: application/json" --url https://slack.com/api/chat.postMessage \
-          -d "{\"channel\": \"${{ inputs.channel }}\", \"text\":\"${{ inputs.text }}\"}"
+        {
+          echo "ts=<<EOF"
+          curl --silent --show-error -X POST -H "Authorization: Bearer ${{ env.SLACK_BOT_TOKEN || inputs.token }}" -H "Content-Type: application/json; charset=utf-8" --url https://slack.com/api/chat.postMessage \
+            -d "{\"channel\": \"${{ inputs.channel }}\", \"thread_ts\":\"${{ inputs.thread_ts }}\", \"text\":\"${{ inputs.text }}\"}" \
+            | jq --raw-output '.ts'
+          echo "EOF"
+        } >> "$GITHUB_OUTPUT"
       shell: bash