修改数据库名后Azure Function Cosmos DB触发器启动报错求助

问题场景 #

在Windows 11系统上使用Azure Cosmos DB模拟器，通过Azure Function的Cosmos DB触发器监听容器变更。修改触发器的数据库名称参数后，启动Function时出现启动失败错误。

错误日志 #

[2023-12-26T17:16:04.200Z] Starting the listener for prefix='', monitoredContainer='business_docs_02', monitoredDatabase='cosmicworks_02', leaseContainer='leases_docs', leaseDatabase='cosmicworks_02', functionId='Host.Functions.MyCoFunc2' failed. Exception: System.InvalidOperationException: This builder instance has already been used to build a processor. Create a new instance to build another.
[2023-12-26T17:16:04.205Z]    at Microsoft.Azure.Cosmos.ChangeFeedProcessorBuilder.Build()
[2023-12-26T17:16:04.211Z]    at Microsoft.Azure.WebJobs.Extensions.CosmosDB.CosmosDBTriggerListener`1.StartProcessorAsync() in D:\a\_work\1\s\src\WebJobs.Extensions.CosmosDB\Trigger\CosmosDBTriggerListener.cs:line 140
[2023-12-26T17:16:04.214Z]    at Microsoft.Azure.WebJobs.Extensions.CosmosDB.CosmosDBTriggerListener`1.StartAsync(CancellationToken cancellationToken) in D:\a\_work\1\s\src\WebJobs.Extensions.CosmosDB\Trigger\CosmosDBTriggerListener.cs:line 96.
[2023-12-26T17:16:04.216Z] The listener for function 'Functions.MyCoFunc2' was unable to start.
[2023-12-26T17:16:04.217Z] The listener for function 'Functions.MyCoFunc2' was unable to start. Microsoft.Azure.Cosmos.Client: This builder instance has already been used to build a processor. Create a new instance to build another.

触发器配置代码 #

public void Run([CosmosDBTrigger(
            databaseName: "cosmicworks_02",
            containerName: "business_docs_02",
            Connection = "DBConnectionString",
            LeaseContainerName = "leases_docs",
            CreateLeaseContainerIfNotExists = true
            )] IReadOnlyList<MyDocument> input)

解决方案 #

• 避免共享CosmosClient实例：确保每个CosmosDBTrigger使用独立的CosmosClient实例。如果在依赖注入中注册了单例CosmosClient，改为使用客户端工厂模式，每次创建新实例供触发器使用，防止ChangeFeedProcessorBuilder被重复调用。
• 清理租约容器数据：修改数据库名称后，旧租约容器（leases_docs）中可能残留了对应旧数据库的租约记录，导致启动冲突。手动删除租约容器内的所有文档，或者直接删除租约容器，让触发器自动重建。
• 更新依赖包版本：检查Microsoft.Azure.WebJobs.Extensions.CosmosDB包的版本，旧版本可能存在Builder复用的bug。升级到最新稳定版后重启Function。
• 重启宿主和模拟器：Function宿主进程可能缓存了旧的Builder实例，重启Function宿主和Cosmos DB模拟器，清除缓存后重新启动。

内容的提问来源于stack exchange，提问作者toto'