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在spring-data-redis-reactive中，写操作返回 redis 执行结果，这使得链接操作符非常困难。以Redis In Action的第 1 章中的示例 reddit 为例。我尝试像这样重新实现：

@Service
public class ArticleService {

    private final ReactiveStringRedisTemplate redisTemplate;

    private final long voteScore = 432L;

    public ArticleService(ReactiveStringRedisTemplate redisTemplate) {
        this.redisTemplate = redisTemplate;
    }

    public Mono<Article> createArticle(Article article) {
        long now = System.currentTimeMillis();
        Map<String, String> newArticle = new HashMap<>();
        newArticle.put("title", article.getTitle());
        newArticle.put("link", article.getLink());
        newArticle.put("poster", article.getPoster());
        newArticle.put("time", String.valueOf(now));
        newArticle.put("votes", "1");
        return redisTemplate.opsForValue()
                            .increment("article:")
                            .doOnNext(id -> redisTemplate.opsForSet().add("voted:" + id.toString(), article.getPoster()).subscribe())
                            .doOnNext(id -> redisTemplate.expire("votes:" + id.toString(), Duration.ofDays(7)).subscribe())
                            .doOnNext(id -> redisTemplate.opsForHash().putAll("article:" + id.toString(), newArticle).subscribe())
                            .doOnNext(id -> redisTemplate.opsForZSet().add("score:", "article:" + id.toString(), now + voteScore).subscribe())
                            .doOnNext(id -> redisTemplate.opsForZSet().add("time:", "article:" + id.toString(), now).subscribe())
                            .map(id -> {
                                article.setId(id);
                                article.setVotes("1");
                                return article;
                            });
    }

}

如您所见，我使用它doOnNext来避免丢失返回的 id 值increment，并且subscribe()在每个中都有一个doOnNext来确保每个 redis 操作都被执行。但我不认为这是推荐的方式。我认为应用程序应该尽量避免subscribe()并主要关注链接流。

做许多redis写操作的正确方法是什么spring-data-redis-reactive？

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1 回答 1

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避免在两者之间订阅，如果您从 WEB 界面调用，Spring 将在最后订阅流。这是一个如何实现的示例

        return redisTemplate.opsForValue()
                            .increment("article:")
                            .flatMap(id -> // Mono.zip will execute concurrently all the modifications below
                              Mono.zip(redisTemplate.opsForSet().add("voted:" + id.toString(), article.getPoster()),
                                  redisTemplate.expire("votes:" + id.toString(), Duration.ofDays(7)),
                                  redisTemplate.opsForHash().putAll("article:" + id.toString(), newArticle),
                                  redisTemplate.opsForZSet().add("score:", "article:" + id.toString(), now + voteScore),
                                  redisTemplate.opsForZSet().add("time:", "article:" + id.toString(), now)
                              )
                                  .map(tuple -> id))
                            .map(id -> {
                                article.setId(id);
                                article.setVotes("1");
                                return article;
                            });

但是您应该考虑将这些修改执行到MULTIRedis 命令中，以确保以原子方式发生https://redis.io/commands/multi。因为您没有任何验证和/或限制，所以不需要 EVAL https://redis.io/commands/eval

于 2020-10-07T00:41:33.360 回答