refactor: mattermost-notify should be a composite action, not a reusable workflow

README.md

@@ -3,15 +3,13 @@ Actions for common tasks in Holochain repositories
 
 ## Mattermost notifier action
 
-Reusable workflow: `.github/workflows/mattermost-notify.yml`
+Composite action: `mattermost-notify/action.yml`
 
 Inputs:
 - `mattermost_url`: base URL for Mattermost (defaults to `https://chat.holochain.org`)
 - `channel_id`: target Mattermost channel ID. This can be obtained by clicking the "(i)" icon at the top right of an open channel.
 - `message`: message text to post
-
-Secret:
-- `MATTERMOST_PERSONAL_ACCESS_TOKEN`: Mattermost personal access token with permission to post in the channel.
+- `mattermost_personal_access_token`: Mattermost personal access token with permission to post in the channel.
 
 Example usage:
 
@@ -23,11 +21,13 @@ on:
 
 jobs:
   notify:
-    uses: holochain/actions/.github/workflows/mattermost-notify.yml@main
-    with:
-      mattermost_url: https://chat.example.com
-      channel_id: your_channel_id
-      message: Hello from GitHub Actions
-    secrets:
-      MATTERMOST_PERSONAL_ACCESS_TOKEN: ${{ secrets.MATTERMOST_PERSONAL_ACCESS_TOKEN }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Send Mattermost message
+        uses: holochain/actions/mattermost-notify@main
+        with:
+          mattermost_url: https://chat.example.com
+          channel_id: your_channel_id
+          message: Hello from GitHub Actions
+          mattermost_personal_access_token: ${{ secrets.MATTERMOST_PERSONAL_ACCESS_TOKEN }}
 ```

mattermost-notify/action.yml

@@ -0,0 +1,29 @@
+name: Mattermost notifier
+description: Send a message to a Mattermost channel
+
+inputs:
+  mattermost_url:
+    description: Base URL for the Mattermost instance (for example, https://example.com)
+    required: false
+    default: https://chat.holochain.org
+  channel_id:
+    description: Mattermost channel ID to post to
+    required: true
+  message:
+    description: Message text to send
+    required: true
+  mattermost_personal_access_token:
+    description: Mattermost personal access token
+    required: true
+
+runs:
+  using: composite
+  steps:
+    - name: Send Mattermost message
+      shell: bash
+      env:
+        MATTERMOST_URL: ${{ inputs.mattermost_url }}
+        MATTERMOST_CHANNEL_ID: ${{ inputs.channel_id }}
+        MATTERMOST_MESSAGE: ${{ inputs.message }}
+        MATTERMOST_PERSONAL_ACCESS_TOKEN: ${{ inputs.mattermost_personal_access_token }}
+      run: "$GITHUB_ACTION_PATH/notify.sh"

mattermost-notify/notify.sh

@@ -0,0 +1,34 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+base_url="${MATTERMOST_URL%/}"
+posts_url="${base_url}/api/v4/posts"
+
+payload="$(jq -cn \
+  --arg channel_id "$MATTERMOST_CHANNEL_ID" \
+  --arg message "$MATTERMOST_MESSAGE" \
+  '{channel_id: $channel_id, message: $message}')"
+
+response_body="$(mktemp)"
+trap 'rm -f "$response_body"' EXIT
+
+response_code="$(curl \
+  --silent \
+  --show-error \
+  --connect-timeout 10 \
+  --max-time 30 \
+  --output "$response_body" \
+  --write-out "%{http_code}" \
+  --request POST "$posts_url" \
+  --header "Authorization: Bearer $MATTERMOST_PERSONAL_ACCESS_TOKEN" \
+  --header "Content-Type: application/json" \
+  --data "$payload")"
+
+if [ "$response_code" -lt 200 ] || [ "$response_code" -ge 300 ]; then
+  printf 'Mattermost API request failed with HTTP %s\n' "$response_code"
+  cat "$response_body"
+  exit 1
+fi
+
+printf 'Message sent to Mattermost channel %s\n' "$MATTERMOST_CHANNEL_ID"