mirror of https://github.com/prometheus/prometheus
52 lines
1.5 KiB
Go
52 lines
1.5 KiB
Go
/*
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Copyright 2017 The Kubernetes Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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// Package transport provides a round tripper capable of caching HTTP responses.
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package discovery
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import (
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"net/http"
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"path/filepath"
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"github.com/gregjones/httpcache"
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"github.com/gregjones/httpcache/diskcache"
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"github.com/peterbourgon/diskv"
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)
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type cacheRoundTripper struct {
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rt *httpcache.Transport
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}
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// newCacheRoundTripper creates a roundtripper that reads the ETag on
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// response headers and send the If-None-Match header on subsequent
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// corresponding requests.
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func newCacheRoundTripper(cacheDir string, rt http.RoundTripper) http.RoundTripper {
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d := diskv.New(diskv.Options{
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BasePath: cacheDir,
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TempDir: filepath.Join(cacheDir, ".diskv-temp"),
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})
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t := httpcache.NewTransport(diskcache.NewWithDiskv(d))
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t.Transport = rt
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return &cacheRoundTripper{rt: t}
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}
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func (rt *cacheRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
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return rt.rt.RoundTrip(req)
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}
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func (rt *cacheRoundTripper) WrappedRoundTripper() http.RoundTripper { return rt.rt.Transport }
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