Loopback: "Unhandled rejection Error: The transaction is not active" when begin 10 transactions at the same time

Question

我有一个使用环回和 postgressql 的 nodejs 项目。

我有一个这样的函数handleTrade，只需启动超时 30 秒的交易，通过 id 查询交易并进行一些更新：

async function handleTrade(id) {
  const { Trade } = app.models;
  const transaction = await Trade.beginTransaction({
    timeout: 30000 // 30 seconds
  });

  try {
    console.log(`${id} - 1`);
    const trade = await Trade.findById(id, { transaction });
    console.log(`${id} - 2`);

    if (trade) {
      // Do some updates with the trade
    }
    transaction.commit();
  } catch (e) {
    console.log(`${id} - 3`, e);
    transaction.rollback();
  }
}

我有一个包含 10 个 ID 的列表，我想异步处理所有这些 ID，并在一切完成后打印 Done。

async function test(ids) {
  const promises = ids.map(id => handleTrade(id));
  await Promise.all(promises);
  console.log('Done');
  process.exit(0);
}

test([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]);

这是日志：

2 - Step 1
3 - Step 1
1 - Step 1
4 - Step 1
6 - Step 1
5 - Step 1
10 - Step 1
9 - Step 1
8 - Step 1
7 - Step 1

-- The process stuck here for 30 seconds (which is the timeout value of the transaction)

2 - Step 2
Unhandled rejection Error: The transaction is not active: 914ca760-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

9 - Step 2
1 - Step 2
3 - Step 2
6 - Step 2
4 - Step 2
5 - Step 2
10 - Step 2
8 - Step 2
Unhandled rejection Error: The transaction is not active: 914e5510-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cce71-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cce70-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cf581-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cf580-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cf582-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914cf583-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Unhandled rejection Error: The transaction is not active: 914e5511-b804-11e8-bb6c-094b32725638
    at process.nextTick (/Users/admin/Work/NIX/nix-project/engine/node_modules/loopback-datasource-juggler/lib/transaction.js:202:12)
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

7 - Step 2
Done

进程在步骤 1 后卡住了 30 秒，然后当事务超时时，它 return 错误 The transaction is not active

只有当我有 10 个 id 时才会发生这种情况，如果我只使用 9 个，运行顺利

test([1, 2, 3, 4, 5, 6, 7, 8, 9]);

// Logs
2 - Step 1
4 - Step 1
5 - Step 1
9 - Step 1
7 - Step 1
8 - Step 1
6 - Step 1
1 - Step 1
3 - Step 1
2 - Step 2
4 - Step 2
9 - Step 2
8 - Step 2
1 - Step 2
5 - Step 2
7 - Step 2
6 - Step 2
3 - Step 2
Done

如果你有任何想法，请帮助我。谢谢

Answer 1

尝试编辑您的数据源文件。

示例：我的 dataresources.json

旧：

{   
  "db": {
    "url": "${DATABASE_URL}",
    "name": "db",
    "connector": "postgresql"
  }
}

新：

{
  "db": {
    "url": "${DATABASE_URL}",
    "name": "db",
    "connector": "postgresql",
    "max": 100
  }
}

说明：你的问题主要是你运行连接池外，这会增加它。（100 只是一个示例数字，您可以将 0 更改为您的 postgresql 配置中定义的最大数字）

Loopback: "Unhandled rejection Error: The transaction is not active" when begin 10 transactions at the same time

Loopback: "Unhandled rejection Error: The transaction is not active" when begin 10 transactions at the same time

javascript

postgresql

loopback

node.js

loopbackjs