github.com/google/cloudprober@v0.11.3/targets/endpoint/endpoint.go (about)

     1  // Copyright 2019 The Cloudprober Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package endpoint provides the type Endpoint, to be used with the
    16  // targets.Targets interface.
    17  package endpoint
    18  
    19  import (
    20  	"sort"
    21  	"strconv"
    22  	"strings"
    23  	"time"
    24  )
    25  
    26  // Endpoint represents a targets and associated parameters.
    27  type Endpoint struct {
    28  	Name        string
    29  	Labels      map[string]string
    30  	LastUpdated time.Time
    31  	Port        int
    32  }
    33  
    34  // Key returns a string key that uniquely identifies that endpoint.
    35  // Endpoint key consists of endpoint name, port and labels.
    36  func (ep *Endpoint) Key() string {
    37  	labelSlice := make([]string, len(ep.Labels))
    38  	i := 0
    39  	for k, v := range ep.Labels {
    40  		labelSlice[i] = k + ":" + v
    41  		i++
    42  	}
    43  	sort.Strings(labelSlice)
    44  
    45  	return strings.Join(append([]string{ep.Name, strconv.Itoa(ep.Port)}, labelSlice...), "_")
    46  }
    47  
    48  // Lister should implement the ListEndpoints method.
    49  type Lister interface {
    50  	// ListEndpoints returns list of endpoints (name, port tupples).
    51  	ListEndpoints() []Endpoint
    52  }
    53  
    54  // EndpointsFromNames is convenience function to build a list of endpoints
    55  // from only names. It leaves the Port field in Endpoint unset and initializes
    56  // Labels field to an empty map.
    57  func EndpointsFromNames(names []string) []Endpoint {
    58  	result := make([]Endpoint, len(names))
    59  	for i, name := range names {
    60  		result[i].Name = name
    61  		result[i].Labels = make(map[string]string)
    62  	}
    63  	return result
    64  }
    65  
    66  // NamesFromEndpoints is convenience function to build a list of names
    67  // from endpoints.
    68  func NamesFromEndpoints(endpoints []Endpoint) []string {
    69  	result := make([]string, len(endpoints))
    70  	for i, ep := range endpoints {
    71  		result[i] = ep.Name
    72  	}
    73  	return result
    74  }