Apache Nifi 简明教程

Apache NiFi - Queues

Apache NiFi 数据流连接有一个队列系统，用来处理大量的数据流入。这些队列可以处理非常大量的 FlowFile，以便处理器按顺序对其进行处理。

The Apache NiFi data flow connection has a queuing system to handle the large amount of data inflow. These queues can handle very large amount of FlowFiles to let the processor process them serially.

queuing system

上图中的队列有 1 个通过成功关系传送的 FlowFile。用户可以通过从下拉列表中选择 List queue 选项来检查 FlowFile。如果发生任何过载或错误，用户还可以通过选择 empty queue 选项清除队列，然后用户可以重新启动流程以再次在数据流中获取那些文件。

The queue in the above image has 1 flowfile transferred through success relationship. A user can check the flowfile by selecting the List queue option in the drop down list. In case of any overload or error, a user can also clear the queue by selecting the empty queue option and then the user can restart the flow to get those files again in the data flow.

list queue

队列中 FlowFile 的列表，包含位置、UUID、文件名、文件大小、队列持续时间和关系持续时间。用户可以通过单击 FlowFile 列表第一列中的信息图标来查看 FlowFile 的所有属性和内容。

The list of flowfiles in a queue, consist of position, UUID, Filename, File size, Queue Duration, and Lineage Duration. A user can see all the attributes and content of a flowfile by clicking the info icon present at the first column of the flowfile list.

flowfile details