Cassandra 3 trigger on delete operation - triggers

Question

I'm trying to implement a trigger on Cassandra 3 to catch delete operations on a specific table by implementing
public Collection<Mutation> augment(Partition partition)
on ITrigger interface but I can't differentiate between update and delete operations.
How can I catch that the operation is a delete operation?

Answer 1

Here is how you can catch all type of deletion
public Collection<Mutation> augment(Partition partition) {
if(partition.partitionLevelDeletion().isLive()) {
UnfilteredRowIterator it = partition.unfilteredIterator();
while (it.hasNext()) {
Unfiltered unfiltered = it.next();
switch (unfiltered.kind()) {
case ROW:
Row row = (Row) unfiltered;
if (!row.deletion().isLive()) {
// Row deletion
}
for (Cell cell : row.cells()) {
if (cell.isTombstone()) {
// Cell deletion
} else {
// Insert or Update
}
}
break;
case RANGE_TOMBSTONE_MARKER:
// Range Deletion
break;
}
}
} else {
// Partition Level Deletion
}
}
Let's say we have the table :
CREATE TABLE kv (
pk int,
ck int,
d int,
PRIMARY KEY (pk, ck)
);
Here pk is the partition key and ck is the clustering key
Partition Level Deletion :
DELETE from kv WHERE pk = 1;
Range Deletion :
DELETE from kv WHERE pk = 1 AND ck > 10;
Row deletion :
DELETE from kv WHERE pk = 1 AND ck = 10;
And cell deletion :
DELETE d from kv WHERE pk = 1 AND ck = 10;