groupbydynamic.md

GroupBy Operator

Overview

Divides an Observable into a dynamic set of Observables that each emit GroupedObservable from the original Observable, organized by key.

GroupByDynamic differs from GroupBy for two reasons:

• We don't need to pass a fixed set length.
• The distribution function is a func(rxgo.Item) string instead of a func(rxgo.Item) int. The rationale is because of possible collisions. For example, if our distribution function produces 128-bit UUIDs, there is a collision risk if such a UUID has to be casted into an int.

Example

count := 3
observable := rxgo.Range(0, 10).GroupByDynamic(func(item rxgo.Item) string {
    return strconv.Itoa(item.V.(int) % count)
}, rxgo.WithBufferedChannel(10))

for i := range observable.Observe() {
    groupedObservable := i.V.(rxgo.GroupedObservable)
    fmt.Printf("New observable: %d\n", groupedObservable.Key)

    for i := range groupedObservable.Observe() {
        fmt.Printf("item: %v\n", i.V)
    }
}

Output:

New observable: 0
item: 0
item: 3
item: 6
item: 9
New observable: 1
item: 1
item: 4
item: 7
item: 10
New observable: 2
item: 2
item: 5
item: 8

Options

• WithBufferedChannel

• WithContext

• WithObservationStrategy

• WithErrorStrategy

• WithPublishStrategy