Hi all I have another Flow variable problem, most likely a syntax error but may be my precursor steps. Objective: I’ve set up a metafield ‘custom.shipping_weight_grams’ which I want to enter the product weight. Sounds easy but there are two scenarios: product has no variants product has var…

Your metafield is a JSON type and you provided it with text. \n 200.0 \n Make sure to remove any whitespace from your liquid around the JSON by using hyphens in your tags like {%- -%} or {{- -}} The gray arrows mean that path was not followed.

Hi there, I think you may be able to avoid that initial condition as well as the “Get product variant data” action by just using a “For each” to loop through the variants returned with the “Product created” trigger, like so: [24-57-9lpwk-z1nfe.png]

Thanks RPiii, I meant to use the productvariant update field but accidentally used the product one. I created the decision fork a couple of steps back when checking the product.hasOnlyDefaultVariant value realising the end point needed to reflect that. I also took out the getproductvariantdata step…

Hi RP I revisited your idea and the setup looked a bit different. The variable field for the Update Product Metafield step now looks like this: {{variantsForeachitem.inventoryItem.measurement.weight.value}} But it still doesn’t work, same error. The full text of the error reads: “Value must be a…

Hi Paul Thanks for your reply. I’ve tried your changes (I actually saw this from you in another discussion) but the same error persists. This is my ‘Update Product Metafield’ setup: [MGRNZ_0-1743374021852.png] and the run analysis: [MGRNZ_1-1743374082485.png]

So first, I’m a bit confused by why you are writing a “product” metafield here for each variant…the last update is going to win. Regarding the error, you didn’t read the part about JSON. You need to be entering JSON not a value. This doc has the various types and their formats: https://shopify.de…

Hi Paul I didn’t understand the significance of the solution when you first mentioned it, I thought the fix was in the liquid for the variable field. I’ve since created metafields with json type and the flow is working as it should. Thanks for your help, very much appreciated. Cheers

Value must be a stringified JSON object with a value (numeric) and unit

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RPiii March 24, 2025, 5:01pm 3

Oh, and you may need to use the Update product variant metafield action instead.

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Value must be a stringified JSON object with a value (numeric) and unit

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