No return data from subflow

Questions
1

This flow calls out to Hudu and retrieves the list of companies. It then pairs down that list to the four that I want. Then it ends. I should be able to call it from another flow and get back the four entries I want. When I do that, the calling flow claims to have an empty array. If I pin the generated array in the calling workflow that workflow operates as expected. So I have a workaround, but I’d like to get my company lookup flow working too. I have upcoming tasks where it will be needed.

Error: No data to show - item(s) exist, but they’re empty

Not really an error.

Output of the last node in that workflow:

[
  {
    "id": 18,
    "name": "Sparkloft Media",
    "tags": "spark"
  },
  {
    "id": 5,
    "name": "ECONorthwest",
    "tags": "econw"
  },
  {
    "id": 7,
    "name": "Hood River Cherry Company",
    "tags": "hrcc"
  },
  {
    "id": 30,
    "name": "Portland Mental Health",
    "tags": "pmhw"
  }
]

Information on your n8n setup

  • Version 1.6.1
  • DB: SQLite
  • Docker on DO
  • Ubuntu 22.04.3 LTS
3

Hi @russellkg, I am sorry you’re having trouble.

Can you confirm where exactly you’re seeing the “No data to show - item(s) exist, but they’re empty” error? Which node is throwing this for you and how exactly does the JSON input of the node look like?

4

In the Execute Workflow node on the right after running the flow.

Screenshot 2023-09-19 at 11.00.55
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Here is a copy of the JSON.

[
  {}
]

Let me know if there’s anything else you need to know.

5

Hey @russellkg

I was having this issue yesterday when creating a subworkflow. If you go into your execution’s and inspect the workflow, see if the data is being sent in there. There does not seem to be a way to see the data that is sent from the main workflow (that I have found yet)

6

Hi Zac,

When I look at the last node in an execution for the subflow, I see data as described in the first message on this thread.

Or did you mean something else?

-Russ

7

So if you take a look here at my Subworkflow you will see that you get the {} showing that there is no data.

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But when you open the “Executions” Tab up the top of the canvas inside the workflow that the data is actually there. It is just not visible as it normally would be.

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I hope this helps a little while you wait :slight_smile:

8

Yeah, it’s not that.

I am seeing the data in the sub workflow, but it’s not being returned to the calling workflow.

If I pin the data shown in the subflow into the Execute a workflow node, the calling workflow works as expected.

9

Hi @russellkg, I won’t be able to run your example workflow seeing it’s using community nodes I don’t have installed and also requires credentials for an external service requiring credentials.

So this is a bit of a hit and miss, but perhaps instead of the Execute Workflow Trigger node you want to use a Webhook trigger node and a Respond to Webhook node in your sub-workflow (and then call this webhook from your parent workflow through an HTTP Request node)? This gives you a bit more control about the response handling and will also make debugging a little easier I think.

10

It appears I have resolved the issue. I basically recreated the workflow. I had some testing to do, and I didn’t want to leave it broken.

While I was testing I noticed the new flow is pulling data as expected.

So this one is done.

-Russ

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