Spring Data Redis using '+inf' to specify unlimited bounds of ZSetOperations.rangeByScore

Question

Using the Redis CLI you can query a sorted set by range with an unlimited upper bound:

zrangebyscore my_key 0 +inf

Represented by the +inf as well as an unlimited lower bound: -inf. This retrieves the range from 0 to the last member.

Spring Data Redis provides an interface to this Redis command through this method signature:

Set<V> rangeByScore(K key, double min, double max, long offset, long count);

and

Set<V> rangeByScore(K key, double min, double max);

These only allow you to supply a double as the bounds.

How do you specify +inf or -inf to the bounds of ZRANGEBYSCORE using Spring Data Redis ?

The only mention of it is in the changelog so it's supported in some way but I can't find any mention of it elsewhere.

Answer 1

Maybe you could use Double.NEGATIVE_INFINITY and Double.POSITIVE_INFINITY to represent -inf and +inf, I've tested on my machine, which works well(with spring-boot-starter-data-redis version=2.2.4.RELEASE) (They are both double values)

Answer 2

In more recent versions you can specify the range with Bound.unbounded().

Flux<V> rangeByScore(K key, Range<Double> range, Limit limit)

For example:

Range.of(Bound.inclusive(start), Bound.unbounded())

See Range class for other factory methods like leftUnbounded / rightUnbounded.

I used this with a redis version below 6.2. With 6.2+ the zrange semantics changed.