failed to read stream, no exist StreamNotFoundError: stream not found

Question

根据文档：

https://developers.eventstore.com/clients/grpc/reading-events.html#reading-backwards-1

下：检查流是否存在

const events = client.readStream("user", {
  direction: FORWARDS,
  fromRevision: BigInt(10),
  maxCount: 20,
});

try {
  for await (const resolvedEvent of events) {
    console.log(resolvedEvent.event?.data);
  }
} catch (error) {
  if (error instanceof StreamNotFoundError) {
    return;
  }

  throw error;
}

我确实得到了：

failed to read stream, no exist StreamNotFoundError: user not found

他们的教程对我来说似乎已经过时了。

问：有没有办法检查 2022 年事件存储中是否存在流（如果不存在，则可能添加？）？

编辑 2：

在尝试之后，它仍然显示提供的答案： node:events:505 扔呃； // 未处理的 'error' 事件 ^

StreamNotFoundError: user not found
    at ReadStream._transform (game\node_modules\@eventstore\db-client\dist\streams\utils\ReadStream.js:50:32)

Answer 1

这里的问题似乎是您正在尝试检查流是否存在在它已经完成调用之后。

将 client.readStream() 移到 try/catch 中可能会有所帮助，直接等待，然后根据需要循环。这至少缩小了出错的范围，并且在 for 循环开始之前就失败了。

try {
// Moved down into try block!
  const events = await client.readStream("user", {
    direction: FORWARDS,
    fromRevision: BigInt(10),
    maxCount: 20,
  });

  for (const resolvedEvent of events) {
    console.log(resolvedEvent.event?.data);
  }
  ...
} catch (error) {...}

Answer 2

我不确定你的数据库中有什么，但我很快复制了示例代码并且它按预期工作

const {EventStoreDBClient, FORWARDS, StreamNotFoundError, START} = require("@eventstore/db-client");

async function main() {
    const CLOUD_ID = "ca1loplo0aepjgt215o0";
    const client   = EventStoreDBClient.connectionString`esdb+discover://${CLOUD_ID}.mesdb.eventstore.cloud`;

    const events = client.readStream("doesntexist", {
        direction:    FORWARDS,
        fromRevision: START,
        maxCount:     20,
    });

    try {
        for await (const resolvedEvent of events) {
            console.log(resolvedEvent.event?.data);
        }
    } catch (error) {
        if (error instanceof StreamNotFoundError) {
            console.log("Stream not found");
            return;
        }

        throw error;
    }
}

main().then(() => console.log("done"));

当我运行它时，我得到：

Stream not found
done

failed to read stream, no exist StreamNotFoundError: stream not found

failed to read stream, no exist StreamNotFoundError: stream not found

javascript

database

eventstoredb