How to handle array of string?

[Saviio]

It looks like this module cannot to convert the data as string[]? Otherwise am I just miss something?

let's say I have some data like this:

let data = [
  {
    id: 1,
    foo: 'foo'
  },
  {
    id: 1,
    foo: 'bar'
  },
  {
    id: 2,
    foo: 'baz'
  }
]

my question is how to make a definition so that it can be used to convert the data like this below.

[
  {
    id: 1,
    foo: ['foo', 'bar']
  },
  {
   id: 2,
   foo: ['baz']
  }
]

[dvalentiate]

hmm, I hadn't considered doing that when I designed the library. I like the idea but haven't fully considered its needs and consequences.

I suspect there will be trouble with implementing a design like this because a set of unique keys is needed for each row of input.

It isn't clear to me how that a mapping would be possible if the source data had two properties that differed per id. In the following example if we wanted foo and bar to be arrays.

let data = [
  {
    id: 1,
    foo: 'foo1',
    bar: 'bar1'
  },
  {
    id: 1,
    foo: 'foo1',
    bar: 'bar2'
  },
  {
    id: 2,
    foo: 'foo2',
    bar: 'bar1'
  }
];

I'm not sure there would be a logical output.

The closest the NestHydration can do at the moment would be to have the input modified to something like the following:

let data = [
  {
    id: 1,
    foo__id: 1,
    foo__value: 'foo'
  },
  {
    id: 1,
    foo__id: 2,
    foo__value: 'bar'
  },
  {
    id: 2,
    foo__id: 3,
    foo__value: 'baz'
  }
];

which could be mapped by nestHydration to this:

let result = NestHydrationJS.nest(data);

// [
  {
    id: 1,
    foo: [
      {id: 1, value: 'foo'},
      {id: 2, value: 'bar'}
    ]
  },
  {
    id: 2,
    foo: [
      {id: 3, value: 'baz'}
    ]
  }
]

which using js array map could get the output you want:

for (let obj of result) {
  obj.foo = obj.foo.map((foo) => foo.value);
}

which would result in the desired output of

// [
  {
    id: 1,
    foo: ['foo', 'bar']
  },
  {
   id: 2,
   foo: ['baz']
  }
];

I still kinda like your idea though, and I think I will have time in the next 2 weeks to consider this further and maybe make a change that would allow for what you proposed. If you want to put a pull request forward yourself I'd certainly appreciate it.

[Saviio]

Hi,

Thanks for your reply, after I post my issue I realized nestHydration can only support the structured data mapping for now. And I just found this problem when I try to write test cases, so this is not a big deal for me currently.

And the solution you mentioned I think it can only help the simple object mapping, if I have a complex object then I have to write a lot of code to make the output right.

P.S:
here's a strange output I got when I try to figure out the problem. Maybe you can use it as this format rule of new feature.

[dvalentiate]

Update

I've come to the conclusion that this array is possible, a good idea, and can be implemented in a consistent manner.

I've implemented a filter that can run after the structure is built but came across a hiccup that makes it not a great option.

I've decided on implementing this array building option inside the core algorithm but it will take a bit of time to get to it.

[jordansoltman]

I'm a little late to the party, but for anyone else who has this issue, I have a fork that handles arrays.

https://github.com/jordansoltman/NestHydrationJS

It also handles composite keys as well. I've made a pull request to bring in the changes.