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61 lines
1.3 KiB
61 lines
1.3 KiB
package random
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import (
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"context"
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"math/rand"
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"github.com/go-kratos/kratos/v2/selector"
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"github.com/go-kratos/kratos/v2/selector/node/direct"
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)
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const (
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// Name is random balancer name
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Name = "random"
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)
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var _ selector.Balancer = (*Balancer)(nil) // Name is balancer name
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// Option is random builder option.
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type Option func(o *options)
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// options is random builder options
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type options struct{}
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// Balancer is a random balancer.
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type Balancer struct{}
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// New an random selector.
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func New(opts ...Option) selector.Selector {
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return NewBuilder(opts...).Build()
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}
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// Pick is pick a weighted node.
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func (p *Balancer) Pick(_ context.Context, nodes []selector.WeightedNode) (selector.WeightedNode, selector.DoneFunc, error) {
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if len(nodes) == 0 {
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return nil, nil, selector.ErrNoAvailable
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}
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cur := rand.Intn(len(nodes))
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selected := nodes[cur]
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d := selected.Pick()
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return selected, d, nil
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}
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// NewBuilder returns a selector builder with random balancer
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func NewBuilder(opts ...Option) selector.Builder {
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var option options
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for _, opt := range opts {
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opt(&option)
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}
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return &selector.DefaultBuilder{
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Balancer: &Builder{},
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Node: &direct.Builder{},
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}
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}
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// Builder is random builder
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type Builder struct{}
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// Build creates Balancer
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func (b *Builder) Build() selector.Balancer {
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return &Balancer{}
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}
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