Travis Patterson
57 lines
1.0 KiB
Go
57 lines
1.0 KiB
Go
package promclient
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import (
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"sort"
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"strings"
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lru "github.com/hashicorp/golang-lru"
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apiv1 "github.com/prometheus/client_golang/api/prometheus/v1"
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)
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type ProviderCache struct {
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provider promClientProvider
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cache *lru.Cache
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}
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type promClientProvider interface {
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GetClient(map[string]string) (apiv1.API, error)
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}
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func NewProviderCache(p promClientProvider) (*ProviderCache, error) {
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cache, err := lru.New(500)
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if err != nil {
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return nil, err
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}
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return &ProviderCache{
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provider: p,
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cache: cache,
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}, nil
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}
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func (c *ProviderCache) GetClient(headers map[string]string) (apiv1.API, error) {
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key := c.key(headers)
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if client, ok := c.cache.Get(key); ok {
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return client.(apiv1.API), nil
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}
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client, err := c.provider.GetClient(headers)
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if err != nil {
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return nil, err
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}
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c.cache.Add(key, client)
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return client, nil
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}
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func (c *ProviderCache) key(headers map[string]string) string {
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vals := make([]string, len(headers))
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var i int
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for _, v := range headers {
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vals[i] = v
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i++
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}
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sort.Strings(vals)
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return strings.Join(vals, "")
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}
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