github.com/yrj2011/jx-test-infra@v0.0.0-20190529031832-7a2065ee98eb/prow/cmd/deck/pluginhelp.go (about)

     1  /*
     2  Copyright 2017 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package main
    18  
    19  import (
    20  	"encoding/json"
    21  	"fmt"
    22  	"net/http"
    23  	"sync"
    24  	"time"
    25  
    26  	"k8s.io/test-infra/prow/pluginhelp"
    27  )
    28  
    29  // cacheLife is the time that we keep a pluginhelp.Help struct before considering it stale.
    30  // We consider help valid for a minute to prevent excessive calls to hook.
    31  const cacheLife = time.Minute
    32  
    33  type helpAgent struct {
    34  	path string
    35  
    36  	sync.Mutex
    37  	help   *pluginhelp.Help
    38  	expiry time.Time
    39  }
    40  
    41  func newHelpAgent(path string) *helpAgent {
    42  	return &helpAgent{
    43  		path: path,
    44  	}
    45  }
    46  
    47  func (ha *helpAgent) getHelp() (*pluginhelp.Help, error) {
    48  	ha.Lock()
    49  	defer ha.Unlock()
    50  	if time.Now().Before(ha.expiry) {
    51  		return ha.help, nil
    52  	}
    53  
    54  	var help pluginhelp.Help
    55  	resp, err := http.Get(ha.path)
    56  	if err != nil {
    57  		return nil, fmt.Errorf("error Getting plugin help: %v", err)
    58  	}
    59  	defer resp.Body.Close()
    60  	if resp.StatusCode < 200 || resp.StatusCode > 299 {
    61  		return nil, fmt.Errorf("response has status code %d", resp.StatusCode)
    62  	}
    63  	if err := json.NewDecoder(resp.Body).Decode(&help); err != nil {
    64  		return nil, fmt.Errorf("error decoding json plugin help: %v", err)
    65  	}
    66  
    67  	ha.help = &help
    68  	ha.expiry = time.Now().Add(cacheLife)
    69  	return &help, nil
    70  }