Record Restorer¶

This stage parses the data records that pass through this stage, filter records that match with the input data of the current batch. The calculation logic of this stage is as follows:

This stage retrieves the cached data from Redis, and output the data records after renaming. This stage has a dependency on the Record Capturer stage.
This stage cannot guarantee idempotence of the calculation results due to failure retries caused by any reasons, such as cluster node exceptions.

Configuration¶

The configuration tabs for this stage are General, Basic, Input/Output, and CacheConfig.

General¶

Name	Required?	Description
Name	Yes	The name of the stage.
Description	No	The description of the stage.
Stage Library	Yes	The streaming operator library to which the stage belongs.
Required Fields	No	The fields that the data records must contain. If the specified fields are not included, the record will be filtered out.
Preconditions	No	The conditions that must be satisfied by the data records. Records that do not meet the conditions will be filtered out. For example, `${record:value('/value') > 0}`. For the syntax of EL expressions, see `Expression Language https://docs.streamsets.com/portal/datacollector/latest/help/datacollector/UserGuide/Expression_Language/ExpressionLanguage_overview.html>`__.
On Record Error	Yes	The processing method for error data. Discard: Error data will be discarded and ignored Send to Error: Error messages will be reported Stop Pipeline: The pipeline will be stopped

Basic¶

Name	Required?	Description
Quality Filter	No	Filter the data according to the data quality. Only records that meet the quality conditions will be processed by this stage.

Input/Output¶

Name	Required?	Description
Input Point	Yes	Specify the input point that triggers the reading of the cached data, using the format {modelId}::{pointId}.
Restore Point	Yes	Specify the point data to be retrieved from the cache, using the format {modelId}::{pointId}.
Output Point	Yes	Specify the output point used for renaming the cached data, using the format {modelId}::{pointId}.

CacheConfig¶

Name

Required?

Description

Cache Type

Yes

Select the storage type for cache data. Options are Redis and Local storage.

Redis: The advantage is that the cached data will not be lost after the stream processing pipeline is paused, restarted, or retried. The disadvantage is that the data processing speed is slow and that it is sensitive to network performance. It is recommended that the network delay should be less than 1ms. Otherwise, the data processing performance will be affected.
Local: The advantage is that the data processing speed is fast. The disadvantage is that the cached data will be lost after the stream processing pipeline is paused, restarted, or retried.

Output Results¶

The data records of the specified device and point will be retrieved from the cache and output after renaming.

Output Example¶

../../../_images/record_restorer_result1.png