javascript - 我的 Rx-js groupJoin 有什么问题

Question

以下代码:

const Rx = require('rx');

const gameRowObservable = Rx.Observable.fromArray([{
    game_id: 1,
    game_name: "game one",
}, {
    game_id: 2,
    game_name: "game two",
}]);
const playerRowObservable = Rx.Observable.fromArray([{
    game_id: 1,
    player_id: 1,
    player_name: "player one",
}, {
    game_id: 1,
    player_id: 2,
    player_name: "player two",
}, {
    game_id: 2,
    player_id: 3,
    player_name: "player three",
}, {
    game_id: 2,
    player_id: 4,
    player_name: "player four",
}]);

const rowObservable = gameRowObservable.
groupJoin(
    playerRowObservable,
    gameRow => Rx.Observable.return(gameRow.game_id),
    playerRow => Rx.Observable.return(playerRow.game_id),
    (gameRow, playerGroup) => playerGroup.toArray().map(playerGroup => Object.assign(gameRow, {
        player_list: playerGroup
    }))
).mergeAll();

rowObservable.subscribe(row => console.log(row));

产生以下结果:

{ game_id: 1, game_name: 'game one', player_list: [] }
{ game_id: 2, game_name: 'game two', player_list: [] }

我想得到这个结果:

[{
    game_id: 1,
    game_name: "game one",
    player_list: [{
        game_id: 1,
        player_id: 1,
        player_name: "player one",
    }, {
        game_id: 1,
        player_id: 2,
        player_name: "player two",
    }]
}, {
    game_id: 2,
    game_name: "game two",
    player_list: [{
        game_id: 2,
        player_id: 3,
        player_name: "player three",
    }, {
        game_id: 2,
        player_id: 4,
        player_name: "player four",
    }]
}]

所以我基本上希望每场比赛的玩家作为数组属性。我做错了什么？

Answer 1

我无法提供有效的解决方案，但我希望能帮助您走上正确的道路。

正如您在 groupJoin 的文档中看到的那样，第二个和第三个参数旨在确定持续时间，而不是确定分组所依据的属性值。

您可以通过重叠进行有效分组，即从发出 gameRowA 开始，在发出下一个 gameRow 之前发出的任何playerRow 都与 gameRowA 分组。由于您不需要任何花哨的分组，因此您的持续时间选择器只是您的源可观察量。请参阅jsbin

const rowObservable = gameRowObservable.
groupJoin(
    playerRowObservable,
    gameRow => gameRowObservable,
    playerRow => playerRowObservable,
    (gameRow, playerGroup) => playerGroup.toArray().map(playerGroup => Object.assign(gameRow, {
        player_list: playerGroup
    }))
).mergeAll();

rowObservable.subscribe(row => console.log(row));