kubernetes/pkg/proxy/config/file.go
2014-06-06 16:40:48 -07:00

112 lines
3.2 KiB
Go

/*
Copyright 2014 Google Inc. All rights reserved.
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.
*/
// Reads the configuration from the file. Example file for two services [nodejs & mysql]
//{"Services": [
// {
// "Name":"nodejs",
// "Port":10000,
// "Endpoints":["10.240.180.168:8000", "10.240.254.199:8000", "10.240.62.150:8000"]
// },
// {
// "Name":"mysql",
// "Port":10001,
// "Endpoints":["10.240.180.168:9000", "10.240.254.199:9000", "10.240.62.150:9000"]
// }
//]
//}
package config
import (
"bytes"
"encoding/json"
"io/ioutil"
"log"
"reflect"
"time"
"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
)
// TODO: kill this struct.
type ServiceJSON struct {
Name string
Port int
Endpoints []string
}
type ConfigFile struct {
Services []ServiceJSON
}
type ConfigSourceFile struct {
serviceChannel chan ServiceUpdate
endpointsChannel chan EndpointsUpdate
filename string
}
func NewConfigSourceFile(filename string, serviceChannel chan ServiceUpdate, endpointsChannel chan EndpointsUpdate) ConfigSourceFile {
config := ConfigSourceFile{
filename: filename,
serviceChannel: serviceChannel,
endpointsChannel: endpointsChannel,
}
go config.Run()
return config
}
func (impl ConfigSourceFile) Run() {
log.Printf("Watching file %s", impl.filename)
var lastData []byte
var lastServices []api.Service
var lastEndpoints []api.Endpoints
for {
data, err := ioutil.ReadFile(impl.filename)
if err != nil {
log.Printf("Couldn't read file: %s : %v", impl.filename, err)
} else {
var config ConfigFile
err = json.Unmarshal(data, &config)
if err != nil {
log.Printf("Couldn't unmarshal configuration from file : %s %v", data, err)
} else {
if !bytes.Equal(lastData, data) {
lastData = data
// Ok, we have a valid configuration, send to channel for
// rejiggering.
newServices := make([]api.Service, len(config.Services))
newEndpoints := make([]api.Endpoints, len(config.Services))
for i, service := range config.Services {
newServices[i] = api.Service{JSONBase: api.JSONBase{ID: service.Name}, Port: service.Port}
newEndpoints[i] = api.Endpoints{Name: service.Name, Endpoints: service.Endpoints}
}
if !reflect.DeepEqual(lastServices, newServices) {
serviceUpdate := ServiceUpdate{Op: SET, Services: newServices}
impl.serviceChannel <- serviceUpdate
lastServices = newServices
}
if !reflect.DeepEqual(lastEndpoints, newEndpoints) {
endpointsUpdate := EndpointsUpdate{Op: SET, Endpoints: newEndpoints}
impl.endpointsChannel <- endpointsUpdate
lastEndpoints = newEndpoints
}
}
}
}
time.Sleep(5 * time.Second)
}
}