PoC for dynamic content API response types

strapi-content-api.ts

import type { Attribute, Common, Utils } from '@strapi/types';

type IDProperty = { id: number };

type InvalidKeys<TSchemaUID extends Common.UID.Schema> = Utils.Object.KeysBy<
  Attribute.GetAll<TSchemaUID>,
  Attribute.Private | Attribute.Password
>;

export type GetValues<TSchemaUID extends Common.UID.Schema> = {
  [TKey in Attribute.GetOptionalKeys<TSchemaUID>]?: Attribute.Get<
    TSchemaUID,
    TKey
  > extends infer TAttribute extends Attribute.Attribute
    ? GetValue<TAttribute>
    : never;
} & {
  [TKey in Attribute.GetRequiredKeys<TSchemaUID>]-?: Attribute.Get<
    TSchemaUID,
    TKey
  > extends infer TAttribute extends Attribute.Attribute
    ? GetValue<TAttribute>
    : never;
} extends infer TValues
  ? // Remove invalid keys (private, password)
    Omit<TValues, InvalidKeys<TSchemaUID>>
  : never;

type RelationValue<TAttribute extends Attribute.Attribute> = TAttribute extends Attribute.Relation<
  infer _TOrigin,
  infer TRelationKind,
  infer TTarget
>
  ? Utils.Expression.MatchFirst<
      [
        [
          Utils.Expression.Extends<TRelationKind, Attribute.RelationKind.WithTarget>,
          TRelationKind extends `${string}ToMany`
            ? Omit<APIResponseCollection<TTarget>, 'meta'>
            : APIResponse<TTarget>,
        ],
      ],
      `TODO: handle other relation kind (${TRelationKind})`
    >
  : never;

type ComponentValue<TAttribute extends Attribute.Attribute> =
  TAttribute extends Attribute.Component<infer TComponentUID, infer TRepeatable>
    ? IDProperty &
        Utils.Expression.If<TRepeatable, GetValues<TComponentUID>[], GetValues<TComponentUID>>
    : never;

type DynamicZoneValue<TAttribute extends Attribute.Attribute> =
  TAttribute extends Attribute.DynamicZone<infer TComponentUIDs>
    ? Array<
        Utils.Array.Values<TComponentUIDs> extends infer TComponentUID
          ? TComponentUID extends Common.UID.Component
            ? { __component: TComponentUID } & IDProperty & GetValues<TComponentUID>
            : never
          : never
      >
    : never;

type MediaValue<TAttribute extends Attribute.Attribute> = TAttribute extends Attribute.Media<
  infer _TKind,
  infer TMultiple
>
  ? Utils.Expression.If<
      TMultiple,
      APIResponseData<'plugin::upload.file'>[],
      APIResponseData<'plugin::upload.file'>
    >
  : never;

export type GetValue<TAttribute extends Attribute.Attribute> = Utils.Expression.If<
  Utils.Expression.IsNotNever<TAttribute>,
  Utils.Expression.MatchFirst<
    [
      // Relation
      [
        Utils.Expression.Extends<TAttribute, Attribute.OfType<'relation'>>,
        RelationValue<TAttribute>,
      ],
      // DynamicZone
      [
        Utils.Expression.Extends<TAttribute, Attribute.OfType<'dynamiczone'>>,
        DynamicZoneValue<TAttribute>,
      ],
      // Component
      [
        Utils.Expression.Extends<TAttribute, Attribute.OfType<'component'>>,
        ComponentValue<TAttribute>,
      ],
      // Media
      [Utils.Expression.Extends<TAttribute, Attribute.OfType<'media'>>, MediaValue<TAttribute>],
      // Fallback
      // If none of the above attribute type, fallback to the original Attribute.GetValue (while making sure it's an attribute)
      [Utils.Expression.True, Attribute.GetValue<TAttribute, unknown>],
    ],
    unknown
  >,
  unknown
>;

interface APIResponseData<TContentTypeUID extends Common.UID.ContentType> extends IDProperty {
  attributes: GetValues<TContentTypeUID>;
}

export interface APIResponseCollectionMetadata {
  page: number;
  pageSize: number;
  pageCount: number;
  total: number;
}

export interface APIResponse<TContentTypeUID extends Common.UID.ContentType> {
  data: APIResponseData<TContentTypeUID>;
}

export interface APIResponseCollection<TContentTypeUID extends Common.UID.ContentType> {
  data: APIResponseData<TContentTypeUID>[];
  meta: APIResponseCollectionMetadata;
}

// TEST

declare function fetchOne<T extends Common.UID.ContentType>(uid: T): Promise<APIResponse<T>>;
declare function fetchMany<T extends Common.UID.ContentType>(
  uid: T
): Promise<APIResponseCollection<T>>;

fetchOne('api::restaurant.restaurant').then((res) => {
  const {
    /* ... */
  } = res.data.attributes;

  console.log(/* ... */);
});

fetchMany('api::restaurant.restaurant').then((res) => {
  res.data.forEach((entity) => {
    const {
      /* ... */
    } = entity.attributes;

    console.log(/* ... */);
  });
});