Flow trigger from custom app doesn't show up in Flow

Shopify Flow
1

Hi all

I made a dev store using the dev dashboard. Then I made an extension-only app using the CLI. I added a flow trigger, following the instructions at Create a Flow trigger using the simplest possible default settings.

But as much as I try, I can’t get the trigger to show up in Flow. I tried app dev, app deploy (no errors). Uninstalled and reinstalled. Same result.
When using dev, the flowTriggerReceive mutation works fine (no errors) if called from the localhost graphiql, but gives “Errors validating schema: Invalid handle ‘trigger’.” when called from the graphiql installed in the dev store.
The trigger shows up in the dev dahsvboard app/version page, but never in the Flow app.

The files package.json, shopify.app.toml, shopify.extension.toml are as defaults/docs.

Sidekick and dev assistant have been unable to find any errors with my setup.

Any help will be much appreciated.

2

Hi Daniel,

How are you attempting to access the trigger in Flow?
I just followed the tutorial and found my trigger with these steps:
Flow app > Create workflow > Select a trigger > My app > My flow trigger

Regarding flowTriggerReceive mutation, you need to run that directly from the app that owns the trigger. In an extension-only app, you can achieve this through an Admin Action extension or an Admin Block extension.

3

Hi Paige

Thanks for your help.

When I go ‘Flow app > Create workflow > Select a trigger‘ my app doesn’t show at all. The only apps I see are Shopify, Flow and Shop.

This is on a brand new dev store (advanced plan) that I generated just for this.

The app with the trigger shows as installed in Settings > Apps, and the trigger is listed in Dev Dashboard > App > versions > active > settings.

4

Can you share your toml file config for the trigger? If you have a handle of “trigger”, it’s possible that your handle is a reserved word or something like that.

Also, are you sure that you are looking for a trigger in Flow and not an action? Triggers only show up when choosing a trigger. Sounds obvious but I’ve confused myself by looking under the action menu.

5

Sure. The toml is:

[[extensions]]
name = “custom trigger”
handle = “custom-trigger”
type = “flow_trigger”
uid = “d5e372e3-ab0a-4ff1-7ba7-ac4c69027197b74be682”
description = “Your description”

[settings]

[[settings.fields]]
type = “single_line_text_field”
key = “customer”
description = “Customer name”

You can see that it shows in the dev details, but neither flow nor graphiql can see it.

Also tried other handles (“my-unique-custom-trigger“) to avoid reserved keywords, but got the same result.

Thanks for your help

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6

@Daniel_G I am having the exact same problem right now with my app. I have tried 20 different hypothesis to get the app to show up as an “Installed App” in the Flow Actions and just cannot get it to be visible.

Seems like people have been trying to fix this issue since 2023 in the discussion forums and nobody has responded with any concrete answer.

7

It sounds like a handle mismatch or schema issue. Make sure your trigger handle matches exactly in your code and shopify.extension.toml (only lowercase letters, numbers, underscores). Also, ensure the extension is fully deployed in the dev store and your app has the right Flow permissions. Sometimes a full app deploy after reinstalling the app fixes visibility in Flow.

8

@Daniel_G, @Pat_DoMore I ran into the exact same problem, nothing worked.

By coincidence, I had a breakthrough today: when I create a new dev store, the Flow app is not installed by default. However, when I check older dev stores (from mid last year), Flow was installed by default.

In those older dev stores with Flow pre-installed, the trigger finally shows up and everything works as expected. I double-checked with two other stores - the only difference is the age of the dev store / whether Flow is pre-installed or not.

Just a guess, but it seems something broke after Shopify switched to the new development store creation process.

9

So you are saying that in dev stores where you manually installed Flow, it’s not working?

10

Yes, exactly! I don’t know if this is the root cause, but there is a difference between new dev stores (without Flow preinstalled) and older dev stores (where Flow was preinstalled) - everything else was the same in my tests.