mirror of https://github.com/k3s-io/k3s
125 lines
3.1 KiB
Go
125 lines
3.1 KiB
Go
/*
|
|
Copyright 2015 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
// Package configz serves ComponentConfig objects from running components.
|
|
//
|
|
// Each component that wants to serve its ComponentConfig creates a Config
|
|
// object, and the program should call InstallHandler once. e.g.,
|
|
// func main() {
|
|
// boatConfig := getBoatConfig()
|
|
// planeConfig := getPlaneConfig()
|
|
//
|
|
// bcz, err := configz.New("boat")
|
|
// if err != nil {
|
|
// panic(err)
|
|
// }
|
|
// bcz.Set(boatConfig)
|
|
//
|
|
// pcz, err := configz.New("plane")
|
|
// if err != nil {
|
|
// panic(err)
|
|
// }
|
|
// pcz.Set(planeConfig)
|
|
//
|
|
// configz.InstallHandler(http.DefaultServeMux)
|
|
// http.ListenAndServe(":8080", http.DefaultServeMux)
|
|
// }
|
|
package configz
|
|
|
|
import (
|
|
"encoding/json"
|
|
"fmt"
|
|
"net/http"
|
|
"sync"
|
|
)
|
|
|
|
var (
|
|
configsGuard sync.RWMutex
|
|
configs = map[string]*Config{}
|
|
)
|
|
|
|
// Config is a handle to a ComponentConfig object. Don't create these directly;
|
|
// use New() instead.
|
|
type Config struct {
|
|
val interface{}
|
|
}
|
|
|
|
// InstallHandler adds an HTTP handler on the given mux for the "/configz"
|
|
// endpoint which serves all registered ComponentConfigs in JSON format.
|
|
func InstallHandler(m mux) {
|
|
m.Handle("/configz", http.HandlerFunc(handle))
|
|
}
|
|
|
|
type mux interface {
|
|
Handle(string, http.Handler)
|
|
}
|
|
|
|
// New creates a Config object with the given name. Each Config is registered
|
|
// with this package's "/configz" handler.
|
|
func New(name string) (*Config, error) {
|
|
configsGuard.Lock()
|
|
defer configsGuard.Unlock()
|
|
if _, found := configs[name]; found {
|
|
return nil, fmt.Errorf("register config %q twice", name)
|
|
}
|
|
newConfig := Config{}
|
|
configs[name] = &newConfig
|
|
return &newConfig, nil
|
|
}
|
|
|
|
// Delete removes the named ComponentConfig from this package's "/configz"
|
|
// handler.
|
|
func Delete(name string) {
|
|
configsGuard.Lock()
|
|
defer configsGuard.Unlock()
|
|
delete(configs, name)
|
|
}
|
|
|
|
// Set sets the ComponentConfig for this Config.
|
|
func (v *Config) Set(val interface{}) {
|
|
configsGuard.Lock()
|
|
defer configsGuard.Unlock()
|
|
v.val = val
|
|
}
|
|
|
|
// MarshalJSON marshals the ComponentConfig as JSON data.
|
|
func (v *Config) MarshalJSON() ([]byte, error) {
|
|
return json.Marshal(v.val)
|
|
}
|
|
|
|
func handle(w http.ResponseWriter, r *http.Request) {
|
|
if err := write(w); err != nil {
|
|
http.Error(w, err.Error(), http.StatusInternalServerError)
|
|
}
|
|
}
|
|
|
|
func write(w http.ResponseWriter) error {
|
|
var b []byte
|
|
var err error
|
|
func() {
|
|
configsGuard.RLock()
|
|
defer configsGuard.RUnlock()
|
|
b, err = json.Marshal(configs)
|
|
}()
|
|
if err != nil {
|
|
return fmt.Errorf("error marshaling json: %v", err)
|
|
}
|
|
w.Header().Set("Content-Type", "application/json")
|
|
w.Header().Set("X-Content-Type-Options", "nosniff")
|
|
_, err = w.Write(b)
|
|
return err
|
|
}
|