GraphQL Admin API - metafieldSet for type list.single_line_text_field

[acerill]

I am trying to use the metafieldsSet mutation (https://shopify.dev/api/admin-graphql/2022-04/mutations/metafieldsSet) for a metafield of type list.single_line_text_field

When I try

value: ['test']

I get the error

Could not coerce value ["test"] to String

And when I try

value: 'test'

I get the error

Value must be an array.

I don't know what else to try or what data type should be used as a value... any suggestion is welcome!

Thanks

[KathB · Accepted solution]

Hi there,

the value needs to be entered as a json string, like so...

 

[rohit_martires]

hey i tried this by converting my array to json via JSON.stringfy(arr) but i'm getting this error 

---

"value": [
┃ "must be a single line text string."
┃ ]  

metafields = await client.post({
    path: 'metafields',
    data: {
      metafield: {
        order_id: `gid://shopify/Order/${order_id}`,
        namespace: "web_3",
        key: "gated_wallet_line_items",
        value: arr,
        type: "list.single_line_text_field",
      }
    },
    type: DataType.JSON
  });

when u check typeof arr its showing string still getting this error tho not sure what i'm doing wrong ?

[acerill]

Just a thought: you are passing type: "list.single_line_text_field" in the API, but does this metafield already have a definition (in the store settings)? Could it be that this definition is not "list.single_line_text_field"?

[rohit_martires]

no i dont have any custom metafields set for the store, btw did JSON.stringify() work for you ?

[acerill]

Yes, it worked for me... but I am using the GraphQL metafieldsSet mutation, it looks like you are using the REST API. Maybe they behave differently.

[acerill]

Oh and for the REST API, I think it's value_type, not type. That could be the issue.

[rohit_martires]

i tried both getting the same error on both rest/graphql
value_type is for the old api version i'm currently using the april_22 version.

[Sam-Deakin]

I have also had problems with this mutation when trying to create or update a metafield with a definition.

The mutation itself seems to require a string value, but passing a string value to try and set, for example, an integer metafield, throws an error because the value can't be coerced to an integer...

[rohit_martires]

if you still have this issue i posted my fix here: https://community.shopify.com/c/shopify-apis-and-sdks/admin-api-metafields-error-value-must-be-a-sin... 🙂