Master n8n Error Workflows: Get Instant Email Alerts on Failures

n8nAging📅 2024-09-12

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AI Agent Architecture

┌─────────────────────────────────────────────────────────────────────┐
│                       AI AGENT FLOW                                 │
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│                                                                     │
│   ┌─────────────┐                                                   │
│   │    USER     │                                                   │
│   │   QUERY     │                                                   │
│   └──────┬──────┘                                                   │
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│   ┌──────────────────────────────────────────────────┐             │
│   │                   AI AGENT                        │             │
│   │  ┌────────────────────────────────────────────┐  │             │
│   │  │              LLM BRAIN                      │  │             │
│   │  │   1. Understand query                       │  │             │
│   │  │   2. Plan approach                          │  │             │
│   │  │   3. Select tools                           │  │             │
│   │  └────────────────────────────────────────────┘  │             │
│   │                      │                           │             │
│   │         ┌────────────┼────────────┐              │             │
│   │         ▼            ▼            ▼              │             │
│   │   ┌──────────┐ ┌──────────┐ ┌──────────┐        │             │
│   │   │  Tool 1  │ │  Tool 2  │ │  Tool 3  │        │             │
│   │   │ Web API  │ │  Files   │ │  Code    │        │             │
│   │   └──────────┘ └──────────┘ └──────────┘        │             │
│   └──────────────────────────────────────────────────┘             │
│          │                                                          │
│          ▼                                                          │
│   ┌─────────────┐                                                   │
│   │  RESPONSE   │                                                   │
│   └─────────────┘                                                   │
│                                                                     │
└─────────────────────────────────────────────────────────────────────┘

Agent Components

• Core concepts explained
• Step-by-step implementation
• Practical examples

Transcript

[00:00] Hi there, I wanted to spend a few minutes talking about error workflows in N8N. I feel like this topic gets overlooked all the time, although it's actually incredibly important for all workflows and super easy to set up. In fact, in this video, I'll show you how to create an error workflow that you can reuse in all of your workflows going forward. This means that if a workflow had to fail for whatever reason, we can automatically trigger an error workflow to handle this exception. And if I quickly

[00:30] show you this error workflow, this workflow simply starts with an error trigger, and this error trigger will have a view of the workflow that failed, the last note that executed, and other important information like the reason for the failure. After that, we can do things like send an email to ourselves, or you can also add to this workflow to send a message on Slack, or maybe you also want to send a message to Discord as an example. This guy really is the limit here, but what we'll do in this

[01:00] video is simply send an email whenever our workflow is filed, and the email will look something like this. It will contain the name of the workflow that failed, along with the date and time of the failure, the last note that was executed, and some other details about the error. Now let's get started. So within N8N, I'm going to create a new workflow, and I'll just call it "Error workflow tutorial". After that, I'm going to add a new trigger, and specifically the "On schedule" trigger, and for

[01:30] argument's sake, I'll say that this trigger runs once a day at midnight. But of course, error workflows work for any other types of automations as well. Go ahead and add one more node, and let's add the HTTP request node. Just for tutorial's sake, I'm going to use one of these placeholder APIs, therefore if you are following along, then go to "jsonplaceholder.typico.com", and scrolling down to the bottom of the page, you'll find these different resources. Let's grab the "Users" resource, and

[02:01] let's copy this entire URL. After that, add the URL to the HTTP request node. That's all we have to do. When you click on "Test step", you should receive a list of names from the JSON placeholder API. We can now test the entire workflow by clicking on "Test workflow", and we get these 10 items back. Now, we're not too worried about these items coming back, but what we want to do is break this workflow. For instance, if we open the HTTP request node, we can introduce some typo into the

[02:32] URL, and when we test this, we will receive an error message. Also, if we go back to the canvas and click on "Test workflow", you'll notice that the workflow is no longer working. This leads us to "Error workflows". Go ahead and save this workflow, and also set it to "active". Then, click on "home", and add a new workflow. Let's call this workflow "Error workflow". After that, click on "Add first step", scroll down to "other ways", and add "Error trigger".

[03:05] After that, click on "Fetch test event". This will just pull in some sample data for us. Once you've done this, go back to the canvas. Let's add a new node. Let's search for "Gmail", and within Gmail, look for the action "Send a message". On the left-hand side, we can see the data coming in from the error trigger, and what we want to do now is set up our Gmail connection, so that we can email some of this information to ourselves. Go ahead and click on "Select Credential", click on "Create new

[03:37] credential", and now we need to enter a client ID and a client secret. This might seem a little bit intimidating, but I promise you it's actually quite simple, and you only have to do this once. After this, you'll be able to use your Gmail account to send emails from all your different workflows, so it's definitely a worthwhile exercise. You should now go to Google Cloud Platform, then under "Projects", create a new project, give it any name that you want, I'll call mine "N8N YouTube

[04:08] Tutorial", then click on "Create". After the project was created, click on "Select project". Alternatively, simply select it from the drop-down over here. We only have to perform three simple steps to get this all working. Step one, go to the menu, and click on "APIs and services". Click on "Gmail API", and click on "Enable". For the second step, we need to set up our OAuth consent screen. So, on the left, click on "OAuth consent screen", select

[04:40] "External", "Create", give your app a name, like "N8N YouTube Tutorial", select your support email, we can skip the logo, the app domains. Let's enter an email address for the developer contact information. Let's click on "Save and continue". We don't have to do anything under "Scopes", so scroll all the way down, and click on "Save and continue". We don't have to do anything for test users, so simply click on "Save and continue", and we don't have to do anything on the summary screen. And finally,

[05:11] we can click on "Credentials", "Create credentials", "OAuth client ID", for the application type, select "Web application", give your web app a name, like "N8N YouTube Tutorial", and under "Authorized redirect URLs", go back to "N8N" and copy this endpoint over here, and add it to "Authorized redirect URIs". Next, click on "Create", and you should now see the client ID and the client secret. Go ahead and copy the client ID, and add it to "N8N",

[05:44] and copy the client secret, and add it to "N8N" as well. Click on "Sign in with Google", select the email address that you want to use for sending the emails. If you receive this error saying that we have not completed the Google verification process, then you can simply go back to Google Cloud, and under "OAuth consent screen", we need to publish this app, so simply click on "Publish app", it's confirmed this, and now "N8N" should work. This means that if we click on "Sign in"

[06:14] again, let's select our email, we can ignore this warning, so click on "Advanced", and continue to "N8N". We can check all of these boxes, and click on "Continue". Now we can close this popup, and our Gmail account is now connected. I know that felt like a lot of setup, but it was well worth it, as you will now be able to send and receive emails from any of your workflows. Continuing with this node, let's select the resource as message, the operation as send, and for the two email, I will send

[06:46] all my errors to this email address. Now let's set up the subject line. I'm going to switch over to "Expression", and click on this button to enlarge this view. I want the subject line to be something like "Workflow" and the workflow name failed. Now obviously this needs to be dynamic, so let's grab the workflow name from the left-hand side, and add it to this string. Great, let's close this, we'll leave the email type as HTML, and let's also build up this message.

[07:18] Let's click on "Expression", click on this button to enlarge this view, and for the body, I want the following information. I want the workflow name, so I'll simply grab the name from the left. I also want the date and time of the failure, and that information is not provided on the left-hand side, but we can inject in variables by adding these double curly braces, and selecting this "now" variable, and that will give us the current timestamp within the system. This date and time doesn't seem

[07:49] correct to you, I will show you how to fix this in a minute. Also want to add information about the last node that was executed, and this is most likely the node that actually failed. For this, let's grab this last node executed value. Below this, add error detail, and let's grab the error message from the left-hand side. Lastly, I also want the error stack, which we can grab from over here as well. That seems good to me. Now, let's go ahead and test this out. Let's

[08:19] close this, let's click on "Test Step", and on the right-hand side, we can see that this was successful, and if I go over to my emails, I received a new mail, all the information is there, but it really doesn't look very good. Now, I don't know about you, but I really don't like spending a lot of time styling email templates. So what we can do to nicely format this is to copy all of this text, and then open up something like chat GPT or Claude, and then simply ask it, create an attractive HTML layout for

[08:50] the following email content, and I'll paste in all the text from N8N. Let's run this, go ahead and copy this code, and then replace all of this in N8N. Let's close this popup, let's click on "Test Step" again, and this time the email should look way better, which it does. Now, let me show you how to correct this timestamp. Effectively, each and every workflow in N8N has some sort of time zone configured against it. You can change the time zone by going to "Settings", and then change the

[09:22] time zone to your local time zone, and then save the workflow, and now the timestamps should be correct. The next step is to hook up our error workflow to our main workflow. So from the dashboard, let's go back to our main workflow. After that, pick on these three dots, go to "Settings", and find "Error Workflow", and change the value to the error workflow that you just created. I'm also going to change this timestamp while I'm here. Next, click on "Save", and whenever

[09:52] this workflow fails, our error workflow should automatically be triggered. Now, one very important thing to note is that you cannot test error workflows manually by clicking "Test Workflow". Yes, this workflow will fail, but this will not trigger your error workflow. However, an error workflow will be triggered by automatic executions. For example, to test this, I'm going to change the interval to minutes, and I'll just set it to 1, so that this workflow runs

[10:23] every minute. We can then save this workflow, and set it to active. Now, we can't activate this workflow because we first have to resolve this error, but I want this thing to fail. So I'll simply go back to the dashboard, I'll open up the workflow again, and then I'll activate it. Great! Because this workflow is now active, it will automatically run every minute. So I'll give it a minute to see if we receive our email, and after waiting a minute, I receive this email, and looking at the contents, this is 100%

[10:54] correct. The note that failed was indeed the HTTP request node, and we know the reason for the failure is because the connection to the API could not be established. So in this video, you've created a reusable error workflow that you can use in any of your projects, and you're also not limited to only sending emails. So if the email component failed, you can also post the same message to Slack, to Discord, save it to Google Sheets, or whatever you want. If you found this video useful, then please hit the like

[11:25] button and subscribe to my channel for more N8N content. Also check out these other N8N videos over here. I'll see you in the next one. Bye-bye!