[fix]Fixed position offset issue during deserialization of ArrowUtil

[Duansg]

What's changed?

Close #3871

Background

When using one-time tasks or private collectors, if a single metric collection returns multiple data entries, the Collector will call responseSyncJobData after all metrics are collected to bundle all results into a single List. ArrowUtil.serializeMetricsData then serializes this List into an Arrow stream containing multiple VectorSchemaRoot objects.Upon receiving the data, the Manager invokes ArrowUtil.deserializeMetricsData. In unpatched versions, this triggers an Unexpected end of input exception, as shown below:

Page waiting timeout

Console error

Caused by: java.io.IOException: Unexpected end of input. Missing schema.
	at org.apache.arrow.vector.ipc.ArrowStreamReader.readSchema(ArrowStreamReader.java:207)
	at org.apache.arrow.vector.ipc.ArrowReader.initialize(ArrowReader.java:178)
	at org.apache.arrow.vector.ipc.ArrowReader.ensureInitialized(ArrowReader.java:171)
	at org.apache.arrow.vector.ipc.ArrowReader.getVectorSchemaRoot(ArrowReader.java:68)
	at org.apache.hertzbeat.common.util.ArrowUtil.deserializeMultipleRoots(ArrowUtil.java:98)
	... 40 common frames omitted

Mock error

 @look org.apache.hertzbeat.common.util.ArrowUtilTest#testSerializeAndDeserializeMetricsData

Reasons

ArrowStreamReader pre-reads data during deserialization, causing positional offsets when consecutively reading multiple Arrow streams and resulting in an Unexpected end of input exception.

Modification details

1. Improved the serialization/deserialization logic of ArrowUtil by adding length-prefixed data, ensuring each Arrow stream can be read with precision.
2. Developed the reproducible test case ArrowUtilTest and passed the test.

Checklist

• I have read the Contributing Guide
• I have written the necessary doc or comment.
• I have added the necessary unit tests and all cases have passed.

Add or update API

• I have added the necessary e2e tests and all cases have passed.

After the repair

[tomsun28]

👍