Accessing FlowFile content in NIFI PutS3Object Processor

Question

I am new to NIFI and want to push data from Kafka to an S3 bucket. I am using the PutS3Object processor and can push data to S3 if I hard code the Bucket value as mphdf/orderEvent, but I want to specify the buckets based on a field in the content of the FlowFile, which is in Json. So, if the Json content is this {"menu": {"type": "file","value": "File"}}, can I have the value for the Bucket property as as mphdf/$.menu.type? I have tried to do this and get the error below. I want to know if there is a way to access the FlowFile content with the PutS3Object processor and make Bucket names configurable or will I have to build my own processor?

ERROR [Timer-Driven Process Thread-10]
o.a.nifi.processors.aws.s3.PutS3Object
com.amazonaws.services.s3.model.AmazonS3Exception: The XML you
provided was not well-formed or did not validate against our
published schema (Service: Amazon S3; Status Code: 400; Error Code:
MalformedXML; Request ID: 77DF07828CBA0E5F)

Answer 1

I believe what you want to do is use an EvaluateJSONPath processor, which evaluates arbitrary JSONPath expressions against the JSON content and extracts the results to flowfile attributes. You can then reference the flowfile attribute using NiFi Expression Language in the PutS3Object configuration (see your first property Object Key which references ${filename}). In this way, you would evaluate $.menu.type and store it into an attribute menuType in the EvaluateJSONPath processor, then in PutS3Object you would have Bucket be mphdf/${menuType}.

You might have to play around with it a bit but off the top of my head I think that should work.