broken data on load app

[aldobel]

Hi, congratulations on the library, I hope you continue to carry out the project. First, I hope the documentation will be completed, as there are still a few features missing. however, the problem that I expose (perhaps due to my inexperience), after I save an object in the database {name: 'name', url: 'url', playlist: [{}]}, when I reopen the app, in the playlist I see:
{name: 'name', url: 'url', playlist: [object Object], [object Object], [object Object]}, and I cannot retrieve the data.
I hope for a resolution. Thanks

[Hieu Nguyen (Jack)]

Welcome, @aldobel.

Did you wrap the fetch function inside onLoaded event?

For example:

componentDidMout() {
  yourdb.onLoaded(this.fetchPlaylists)
}

fetchPlaylists = () => {
  // fetch playlist code
}

[aldobel]

Thanks for the reply. Unfortunately I have already tried with this code:

useEffect(() => {
    Liste.onLoaded(() => setValueListe(lis()));
  }, []);

  const lis = () => {
    Liste.data();
  };

but the answer is always this:

[
    {
        "id": "61a69ac2f0MKO9fk0009p6bJ",
        "namePlaylist": "Lista",
        "urlPlaylist": "url",
        "live": "[object Object],[object Object],[object Object],[object Object],[object Object]",
    }
]

[Hieu Nguyen (Jack)]

Can you show your data schema? Do you use reference data type for live?

(Note that it doesn't support nested objects at the moment)

[aldobel]

This is my Schema:

export class listSchema {
  name = "Liste";
  props = {
    namePlaylist: "string",
    urlPlaylist: "string",
    live: [],
  };
}

I must therefore specify the object that will go live, for example:

export class listSchema {
  name = "Liste";
  props = {
    namePlaylist: "string",
    urlPlaylist: "string",
    live: [{
       name: 'string',
       info: '?string'
    }],
  };
}

Thanks!

[Hieu Nguyen (Jack)]

Ok, since vasern isn't support nested object yet, you'll need to have another schema and use it as a reference. For example

class Item {
... // Schema code
}

export class listSchema {
  name = "Liste";
  props = {
    namePlaylist: "string",
    urlPlaylist: "string",
    // [] is for list/array
    // # is for reference
    live: "[]#Item"
  };
}

[aldobel]

I just did this, but I don't know if I got something wrong:

class Item {
  name = "Item";
  props = {
    group: "?string",
    url: "?string",
    name: "?string",
    logo: "?string",
  };
}

export class listSchema {
  name = "Liste";
  props = {
    namePlaylist: "string",
    urlPlaylist: "string",
    live: "[]#Item",
  };
}

const VasernDB = new Vasern({
  schemas: [listSchema],
  version: 1,
});

Now he gives me:

{
"id": "61a7b6b8gprd0pSF000tXqjv",
"namePlaylist": "Lista 2",
"urlPlaylist": "url",
"live_id": ["" ],
}

[Hieu Nguyen (Jack)]

This version of Vasern is still a bit handy:

1. You need to pass all schema when creating a new Vasern instance
2. When getting the results, a list of references ([]#Item in this case) will only return ids of the item. You'll need to manually get items from the Item collection using the filter function

The following code should works

class ItemSchema {
  name = "Item";
  props = {
    group: "?string",
    url: "?string",
    name: "?string",
    logo: "?string",
  };
}

class ListSchema {
  name = "List";
  props = {
    name: "string",
    url: "string",
    items: "[]#Item",
  };
}

const VasernDB = new Vasern({
  schemas: [ListSchema, ItemSchema], // all schema here
  version: 1,
});

const { List, Item } = VasernDB;

// Insert items and create a list
const insertItems = Item.insert([{...}]);
const insertedLists = List.insert({ 
  name: "List 1",
  url: "list/url",
  items: insertedItems
})

// Get data
VasernDB.onLoaded(() => {
  const firstList = List.data()[0];

  // Need to get items from Item collection using filter
  const firstListItems = Item.filter(item => firstList.items.indexOf(item.id) !== -1).data();
  console.log({ list: firstList, items: firstListItems })
})

By the way, Vasern is still pretty much a work-in-progress and I haven't been able to work on Vasern for some time. I'd highly recommend using an alternative (WatermelonDB, Realm, etc)

[aldobel]

Ok, as soon as I can I try and let you know. A thousand thanks