List Objects v2 Handler failed to parse xml

Question

Hello,

I am using a Snowflake integration with S3 to load files.  When I attempt to do a copy from the bucket location I get the following error:

Failure using stage area in [AWS_S3] after multiple attempts. Cause: [Failed to parse XML document with handler class com.amazonaws.services.s3.model.transform.XmlResponsesSaxParser$ListObjectsV2Handler]. This is usually due to a temporary failure condition with the cloud provider. Try again.

I am trying to understand the root cause of this issue.  The bucket in question has millions of paths with a partition strategy for each id.  ({bucket_name}/production/{system}/{id}/{file}).

I've reached out to Snowflake support and from their internal logs they are seeing this error:

AWS exception is transient, exception type=org.xml.sax.SAXParseException. ex = Character reference "" is an invalid XML character.

I have been able to successfully list other paths within the same bucket, however I am unable to in our production path.  I believe this can be due to the number of objects in the bucket and a failure in our bucket partition strategy.  At this point I am scoping out the project and seeing if I should recommend a change in our partition strategy, or if this could simply be related to the name of directory in the path.

Thank you for taking the time to help with this question!

Answer

The error about the invalid XML character (`Character reference "" is an invalid XML character`), suggests that the issue is with the data (likely object names or metadata) in your *S3 bucket* rather than a direct issue with *Snowflake* or the *AWS infrastructure*. *XML* parsing errors usually happen when the *XML document* (in this case, the response from an *S3 API call*) contains characters or sequences that are not allowed in *XML documents*. The `` is a representation of a control character in the *XML*, which is not allowed in *XML 1.0 documents*.

#### Recomendation
Before recommending a change in your partition strategy, it's crucial to identify if the issue is widespread or isolated to a few objects. If isolated, simply correcting the problematic object names or metadata may suffice. However, if the issue is indicative of a broader problem with how data is partitioned or named, then revising the partitioning strategy to ensure scalability and compliance with best practices for object naming in *S3* might be necessary.

List Objects v2 Handler failed to parse xml

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