Slack Integration Guide

Send messages to Slack channels and users directly from your pipelines. This guide covers Slack App setup, connection configuration, and function creation for automated notifications.

Overview

The Slack connector enables you to:

• Send channel messages to notify teams about production events, alerts, and workflow updates
• Send direct messages to individual users for targeted notifications
• Authenticate via OAuth tokens using Bot Tokens (xoxb-) or User Tokens (xoxp-)
• Customize bot appearance with custom display names and emoji icons (Bot Token only)
• Thread replies to keep conversations organized with threaded messages
• Dynamic recipient selection with searchable channel and user dropdowns

Bot vs User Tokens

The Slack connector supports both Bot Tokens (xoxb-) and User Tokens (xoxp-). Bot tokens are recommended for most use cases — they support username and icon customization and operate independently of any user account.

Prerequisites

Before creating a Slack connection in MaestroHub, you need to:

1. Slack Workspace: Have access to a Slack workspace where you want to send messages
2. Slack App: Create a Slack App at api.slack.com/apps
3. OAuth Scopes: Configure the required API scopes for your app
4. App Installation: Install the app to your workspace and obtain an OAuth token

Slack App Setup

Step 1: Create a Slack App

1. Go to api.slack.com/apps
2. Click Create New App
3. Choose From scratch
4. Enter an app name (e.g., MaestroHub Notifications)
5. Select the workspace where the app will be installed
6. Click Create App

Step 2: Configure OAuth Scopes

Navigate to OAuth & Permissions in the left sidebar and add the following scopes:

Required Scopes

Scope	Purpose
chat:write	Send messages to channels and users

Conditional Scopes

Scope	Purpose
channels:read	List public channels (for dropdown selection in MaestroHub)
groups:read	List private channels (for dropdown selection in MaestroHub)
users:read	List workspace users (for direct message recipient selection)

Optional Scopes

Scope	Purpose
chat:write.customize	Custom bot display name and icon emoji

Scope Impact

• Without conditional scopes: You can still send messages by manually entering Channel ID or User ID
• With conditional scopes: MaestroHub can populate searchable dropdown lists of channels and users for easier configuration

Step 3: Install the App

1. Navigate to OAuth & Permissions
2. Click Install to Workspace
3. Review and authorize the requested permissions
4. Copy the Bot User OAuth Token (xoxb-...) or User OAuth Token (xoxp-...)

warning

Copy the OAuth token immediately after installation. If you add new scopes later, you must reinstall the app to your workspace and copy the updated token.

Connection Configuration

Creating a Slack Connection

Navigate to Connections → New Connection → Slack and configure the following:

Slack Connection Creation Fields

1. Profile Information

Field	Default	Description
Profile Name	-	A descriptive name for this connection profile (required, max 100 characters)
Description	-	Optional description for this Slack connection

2. OAuth Token

Field	Default	Description
OAuth Token	-	Bot Token (xoxb-...) or User Token (xoxp-...) from your Slack App (required, stored encrypted)

Token Types

• Bot Token (xoxb-): Recommended. Supports custom bot name and icon emoji. Operates independently of user accounts.
• User Token (xoxp-): Messages are sent as the authenticated user. Does not support username/icon customization.

3. Connection Labels

Field	Default	Description
Labels	-	Key-value pairs to categorize and organize this Slack connection (max 10 labels)

Example Labels

• env: prod – Environment
• service: notifications – Connection purpose
• team: operations – Responsible team

Notes

• Required Fields: Profile Name and OAuth Token must be filled.
• Security: The OAuth token is stored encrypted and masked on edit. Leave the field empty to keep the stored value.
• Rate Limit: Slack allows approximately 1 message per second (short bursts are permitted).

Function Builder

Creating Slack Functions

After saving the connection:

1. Go to Functions → New Function (or use the Functions tab in the connection editor)
2. Select the function type (Send Message, Get Channels, Get Users)
3. Choose the Slack connection profile
4. Configure function parameters

Create reusable Slack functions for channel and direct messaging

Send Message Function

Purpose: Send a text message to a Slack channel or directly to a user. Ideal for automated notifications, alerts, production updates, and status messages from your pipelines.

Configuration Fields

Field	Type	Required	Default	Description
Function Name	String	Yes	-	A descriptive name for this function (e.g., notify-production-alerts). Max 100 characters
Send Message To	Select	Yes	Channel	Choose whether to send the message to a Channel or a User (direct message)
Channel	String	Conditional	-	Slack channel to send the message to. Use the searchable dropdown or enter a Channel ID manually. Supports parameters: ((channelId))
User	String	Conditional	-	Slack user to send a direct message to. Use the searchable dropdown or enter a User ID manually. Supports parameters: ((userId))
Message Text	String	Yes	-	Message content to send. Supports template parameters: ((message)), ((alertDetails))
Bot Username	String	No	-	Override the bot display name (Bot Token only). Requires chat:write.customize scope
Icon Emoji	String	No	-	Override the bot icon with an emoji, e.g., :robot_face: (Bot Token only). Requires chat:write.customize scope
Thread Timestamp	String	No	-	Reply in a thread by specifying the parent message timestamp. Supports parameters: ((threadTs))

note

• Channel is required when "Send Message To" is set to Channel
• User is required when "Send Message To" is set to User
• Bot Username and Icon Emoji are only available with Bot Tokens (xoxb-)

Use Cases: Channel notifications, alert broadcasting, status updates, automated announcements, direct user alerts

Using Parameters

Use ((parameterName)) in supported fields to create dynamic, reusable messaging functions with content injected at runtime from your pipeline data.

Field	Supports Templating
Channel (manual mode)	Yes
User (manual mode)	Yes
Message Text	Yes
Bot Username	Yes
Icon Emoji	Yes
Thread Timestamp	Yes

Configuration	Description	Example
Type	Validate incoming values	string, number, boolean, datetime, json, buffer
Required	Enforce presence	Required / Optional
Default Value	Provide fallbacks	'default-channel', 'Alert'
Description	Document intent	"Target channel for notifications", "Alert message body"

Pipeline Integration

Use the Slack messaging functions you configure here as nodes inside the Pipeline Designer to send notifications and integrate team communication into your automation workflows. Drag function nodes onto the canvas, bind parameters to upstream outputs or constants, and route messages based on your business logic.

For end-to-end orchestration ideas, such as combining Slack notifications with database queries, MQTT events, REST API calls, or OPC UA data, explore the Connector Nodes page.

Common Use Cases

Production Alert Notification

Scenario: Notify the operations team immediately when a machine fault is detected.

Pipeline Flow:

1. OPC UA Read node monitors machine status tag
2. Filter node detects status = "fault"
3. Slack Send Message node sends alert to #production-alerts channel

Function Configuration:

Function: Send Message
Send To: Channel
Channel: #production-alerts
Message Text: ⚠️ *Machine Fault Detected*
  Machine: ((machineName))
  Status: ((status))
  Error Code: ((errorCode))
  Action Required: Immediate inspection

---

Quality Threshold Breach

Scenario: Send a direct message to the quality manager when a measurement goes out of tolerance.

Function Configuration:

Function: Send Message
Send To: User
User: ((qualityManagerId))
Message Text: 🔴 Quality Alert — ((partNumber))
  Measurement: ((measuredValue)) (Tolerance: ((minTolerance)) – ((maxTolerance)))
  Line: ((productionLine))
  Time: ((timestamp))

---

Shift Handover Summary

Scenario: Post an automated shift summary to a dedicated Slack channel at the end of each shift.

Function Configuration:

Function: Send Message
Send To: Channel
Channel: #shift-handover
Message Text: 📋 *Shift Summary — ((shiftName))*
  Total Production: ((totalUnits)) units
  Defects: ((defectCount))
  OEE: ((oeePercent))%
  Notes: ((operatorNotes))
Bot Username: ShiftBot
Icon Emoji: :clipboard: