Apache Pig - Convert bytearray(json) to bag or maps?

Apache Pig - Convert bytearray(json) to bag or maps?

Here X contains one column named 'metadata' of type bytearray. But the actual content is a JSON i.e. the d is a JSON (keys as sId & cId) as shown below:

grunt> describe X
X: {metadata: bytearray}
grunt> dump X
({"sId":"003_w","cId":"k"})
({"sId":"001_rf","cId":"r"})
({"sId":"001_rf","cId":"r"})
({"sId":"004_rf","cId":"r"})

Any idea how can I generate cId & sId as separate chararray columns?