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How to patch a field of an object in an array using the Sanity JavaScript client

7 replies
Last updated: May 29, 2023
Hey guys !I'm trying to patch a field of an object in an array with the js client, but I don't see how it's possible in a clean way.
Let's says I have something like this :

    "_id": 'aFuiYGWUw0SSAvMnYQafry',
    "entries": [
            "_key": "BjDASDLOMkBsqk1tqRecKu"
            ...other keys and values
            "_key": "E0vulMwINU3H9ETBqXnRT7",
            ..oher keys and values
            "subentries": [
                    "data": "saved datas",
                    "_key": "6b8c867d-36b9-4eff-97e0-9fd5be6c6ee4"
                => insert data here
For now, the only solution I found was to fetch the entire document, edit the result in JS and patch with the full data.
• It is not very clean, and need another request
• I lost some fields value, even if I checked that all data was there
Any better idea ?
May 24, 2023, 10:22 PM
user Q
, just I'm not sure yet what you're looking for...
Have a look at the first example on this doc page for patches -- it's not requesting any other records to do the `patch`; you'd just send this mutation query through the client, no?
You might need another query to get the values to fill in, but isn't that natural?

Clean if needed, for me anyway, but it could well be I'm missing what's really your concern here, so far....

Best, (Removed Name)
May 25, 2023, 3:45 AM
Let’s say I want to replace the value of a field in the second object of an array. I don’t see how I can use the index or the key there to updte a specific target without touching the others
May 25, 2023, 7:21 AM
Well, a patch lets you focus on just one object and one field in it, if you want, doesn't it?
I'm viewing this that you are targeting that object in the patch, not the array holding it, which shouldn't need touching?
May 25, 2023, 7:26 AM
hm, I think I got it :I was looking for a condition like this :
{ "set": { "body[_type==\"cta\"].text": "Do the thing!" } }

  "mutations": [
      "patch": {
        "id": "aFuiYGWUw0SSAvMnYQafry",
        "set": {
          "entries"[_key==\"E0vulMwINU3H9ETBqXnRT7\"] : {
            "insert": {
              "after": "subentries[-1]",
              "items": ["=> insert data here"]
I will try this later, thanks
user Q
May 25, 2023, 8:11 AM
Most welcome, (Removed Name), and glad you saw into it :)
May 25, 2023, 8:12 AM
Hey ! just to confirm I was on the right path, this works like a charm (js client)
            [`entries[_key==\"${entryId}\"].subentries`]: []
        .append(`entries[_key==\"${entryId}\"].subentries`, [{
            _key: uuid(),
            ...=> data here
May 28, 2023, 11:01 PM
Good man :) Looks like you covered the angles nicely, and this will be good for others to find. Take care, (Removed Name), (Removed Name) (we're having a long weekend over here, so things will be quiet)
May 29, 2023, 4:01 AM

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