Hello and welcome to this video on using Inject and Debug nodes in Muse Automator.   
The Inject node lets you create and send messages into a flow either manually with a click or on a schedule.  It’s perfect for testing functions, formatting payloads, or simulating devices and events.
The Debug node displays the outputs of nodes, like msg.payload, or the entire message object in the Debug sidebar.  The Debug node is your window into what’s really happening inside your flow.
We will start by building a simple flow with just an inject and a debug node.   Click and drag in an inject node from the node pallet on the left and drop it on your canvas.  Now we will drag in a Debug node and drop that onto the canvas.
Next, wire these two nodes together by clicking and dragging the output of the inject node over to the input of the debug node.   Please note that it is not necessary to connect to a controller for this simple example, so a controller node is not necessary.   
Deploy the project so that the flow we just created is running.   Select the Debug Messages tab in the right sidebar; this is where messages from your debug node will be displayed.  You can also press the trash can icon in the debug messages sidebar to clear any existing messages.  
Click the button on the left of the inject node to inject the message into your flow, and you will see a message appear in your debug sidebar.   We’ll look deeper into these messages shortly; the only important thing for now is that a message appears.
Now that we have a basic message being sent to our debug sidebar, let’s explore these nodes a little more closely.   Double-click the Inject node to open the settings for that node.   We can start by using the Name field to give the node a friendly name.   
It is important to make sure that each node has a unique and easily identifiable name.   This is especially important as the size and complexity of your projects increases.   No one wants to open up every single node to find out what it does.
Next, select the down arrow next to msg.payload to choose which data type to use.  There are multiple data type options to choose from, but for this example we will use string and enter ‘Hello World’ in the field.  We will also use the string data type for msg.topic and enter the string ‘Training’.  

 
Looking at the bottom of the Inject node settings, you will see some options that we will not be using in this video, but you will want to be aware of.   The +add button allows you to add more message properties to your message.   
“Inject once after” is used to automatically send a message when the flow is deployed or the program starts.   It also has a configurable delay.   The Repeat option allows you to configure your message to repeat based on a variety of different interval types.
Now, press the Inject Now button and you will see the Hello World message in your debug sidebar, but notice that you do not see msg.topic displayed.  This is because by default the debug node only displays msg.payload but we can configure this node to show the data that we want.   Close the inject node settings by pressing the Done button and open the debug node settings by double clicking on the debug node.  
The Output section allows you to adjust what data is displayed in the debug sidebar.   For this example, we are going to choose the ‘complete msg object’ option, and we will check both the debug window and node status options.  We will also use the Name field to give this debug node a friendly name of “From Inject”.  This makes it easier to find in the debug sidebar when you have multiple debug nodes displaying data.   Now we can press Done on the debug node settings, press Deploy and clear the existing debug messages with the trash can icon.  
Next, press the button on the Inject node to send our message.  You will now see that string we configured for msg.payload is displayed under the debug node; this is from the node status checkbox.  In the debug sidebar, it will show the friendly name of the debug node we configured which received the message and the message data has more information than before.  Click the arrow next to the debug data to expand the message object to show all properties.  
With the object expanded you can now see both msg.payload and msg.topic object properties and their values.