func watch(
client *consulapi.Client,
prefix string,
path string,
token string,
pairCh chan<- consulapi.KVPairs,
errCh chan<- error,
quitCh <-chan struct{}) {
// Create the root for KVs, if necessary
mkdirp.Mk(path, 0777)
// Get the initial list of k/v pairs. We don't do a retryableList
// here because we want a fast fail if the initial request fails.
opts := &consulapi.QueryOptions{Token: token}
pairs, meta, err := client.KV().List(prefix, opts)
if err != nil {
errCh <- err
return
}
// Send the initial list out right away
pairCh <- pairs
// Loop forever (or until quitCh is closed) and watch the keys
// for changes.
curIndex := meta.LastIndex
for {
select {
case <-quitCh:
return
default:
}
pairs, meta, err = retryableList(
func() (consulapi.KVPairs, *consulapi.QueryMeta, error) {
opts = &consulapi.QueryOptions{WaitIndex: curIndex, Token: token}
return client.KV().List(prefix, opts)
})
if err != nil {
// This happens when the connection to the consul agent dies. Build in a retry by looping after a delay.
log.Warn("Error communicating with consul agent.")
continue
}
pairCh <- pairs
log.WithFields(log.Fields{
"curIndex": curIndex,
"lastIndex": meta.LastIndex,
}).Debug("Potential index update observed")
curIndex = meta.LastIndex
}
}
func main() {
reader := bufio.NewReader(os.Stdin)
fmt.Println("aiw3/maps 0.1.1")
fmt.Print("Please type which kind of files you want to download [client/server]: ")
cur_type, err := reader.ReadString('\n')
cur_type = strings.Trim(cur_type, "\n\r")
if err != nil {
fmt.Println(err)
os.Exit(1)
}
if cur_type != "client" && cur_type != "server" {
fmt.Println("Invalid type")
os.Exit(1)
}
fmt.Println("Loading packages list...")
resp, err := http.Get("https://cloudrack.io/aiw3/maps.json")
if err != nil {
fmt.Printf("Error while downloading map data; %s", err)
os.Exit(1)
}
defer resp.Body.Close()
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
fmt.Printf("Error while downloading map data; %s", err)
os.Exit(1)
}
var maps Maps
err = json.Unmarshal(body, &maps)
if err != nil {
fmt.Printf("Error while parsing map data; %s", err)
os.Exit(1)
}
fmt.Println("Verifying repository's integrity...")
for _, pkg := range maps.Packages {
for name, _ := range pkg.Files {
if _, exists := maps.Files[name]; !exists {
fmt.Printf("Invalid repository; File %s does not exist (required by %s).\n", name, pkg.Id)
os.Exit(1)
}
}
}
fmt.Println("Choose the map to install:")
for i, pkg := range maps.Packages {
fmt.Printf("[%d] %s (%s)\n", i, pkg.Name, pkg.Id)
}
fmt.Printf("[%d] All files (both client and server)\n", len(maps.Packages))
fmt.Print("Type in the ID of the map you want to install: ")
input, err := reader.ReadString('\n')
if err != nil {
fmt.Println(err)
os.Exit(1)
}
i, err := strconv.Atoi(strings.Trim(input, "\r\n"))
if err != nil {
fmt.Println(err)
os.Exit(1)
}
if i > len(maps.Packages) || i < 0 {
fmt.Println("Package does not exist.")
os.Exit(1)
}
if i < len(maps.Packages) {
pkg := maps.Packages[i]
for name, side := range pkg.Files {
if side == "shared" || side == cur_type {
abs, err := filepath.Abs(name)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
if utility.FileExists(abs) {
fmt.Println(name + " already exists")
continue
}
dir := filepath.Dir(abs)
err = mkdirp.Mk(dir, 755)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
fmt.Printf("Downloading %s\n", name)
var cmd *exec.Cmd
if runtime.GOOS == "windows" {
cmd = exec.Command("megatools/megadl", "--path="+dir, maps.Files[name])
} else {
cmd = exec.Command("megadl", "--path="+dir, maps.Files[name])
}
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
err = cmd.Run()
if err != nil {
fmt.Println(err)
os.Exit(1)
}
}
}
} else {
for name, url := range maps.Files {
abs, err := filepath.Abs(name)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
if utility.FileExists(abs) {
fmt.Println(name + " already exists")
continue
}
dir := filepath.Dir(abs)
err = mkdirp.Mk(dir, 755)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
fmt.Printf("Downloading %s\n", name)
cmd := exec.Command("megatools/megadl", "--path="+dir, url)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
err = cmd.Run()
if err != nil {
fmt.Println(err)
os.Exit(1)
}
}
}
fmt.Println("Install completed.")
}
// Connects to Consul and watches a given K/V prefix and uses that to
// write to the filesystem.
func watchMappingAndExec(config *WatchConfig, mappingConfig *MappingConfig) (int, error) {
client, err := buildConsulClient(config.Consul)
if err != nil {
return 0, err
}
// If prefix starts with /, trim it.
if mappingConfig.Prefix[0] == '/' {
mappingConfig.Prefix = mappingConfig.Prefix[1:]
}
// If the config path is lacking a trailing separator, add it.
if mappingConfig.Path[len(mappingConfig.Path)-1] != os.PathSeparator {
mappingConfig.Path += string(os.PathSeparator)
}
isWindows := os.PathSeparator != '/'
// Remove an unhandled trailing quote, which presented itself on Windows when
// the given path contained spaces (requiring quotes) and also had a trailing
// backslash.
if mappingConfig.Path[len(mappingConfig.Path)-1] == 34 {
mappingConfig.Path = mappingConfig.Path[:len(mappingConfig.Path)-1]
}
// Start the watcher goroutine that watches for changes in the
// K/V and notifies us on a channel.
errCh := make(chan error, 1)
pairCh := make(chan consulapi.KVPairs)
quitCh := make(chan struct{})
// Defer close of quitCh if we're running more than once
if !config.RunOnce {
defer close(quitCh)
}
go watch(
client, mappingConfig.Prefix, mappingConfig.Path, config.Consul.Token, pairCh, errCh, quitCh)
var env map[string]string
for {
var pairs consulapi.KVPairs
// Wait for new pairs to come on our channel or an error
// to occur.
select {
case pairs = <-pairCh:
case err := <-errCh:
return 0, err
}
newEnv := make(map[string]string)
for _, pair := range pairs {
log.WithFields(log.Fields{
"key": pair.Key,
}).Debug("Key present in source")
k := strings.TrimPrefix(pair.Key, mappingConfig.Prefix)
k = strings.TrimLeft(k, "/")
newEnv[k] = string(pair.Value)
}
// If the variables didn't actually change,
// then don't do anything.
if reflect.DeepEqual(env, newEnv) {
continue
}
// Iterate over all objects in the current env. If they are not in the newEnv, they
// were deleted from Consul and should be deleted from disk.
for k := range env {
if _, ok := newEnv[k]; !ok {
log.WithFields(log.Fields{
"key": k,
}).Debug("Key no longer present locally")
// Write file to disk
keyfile := fmt.Sprintf("%s%s", mappingConfig.Path, k)
if isWindows {
keyfile = strings.Replace(keyfile, "/", "\\", -1)
}
err := os.Remove(keyfile)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Failed to remove key")
}
}
}
// Replace the env so we can detect future changes
env = newEnv
// Write the updated keys to the filesystem at the specified path
for k, v := range newEnv {
// Write file to disk
keyfile := fmt.Sprintf("%s%s", mappingConfig.Path, k)
// if Windows, replace / with windows path delimiter
if isWindows {
keyfile = strings.Replace(keyfile, "/", "\\", -1)
// mkdirp the file's path
err := mkdirp.Mk(keyfile[:strings.LastIndex(keyfile, "\\")], 0777)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Failed to create parent directory for key")
}
} else {
// mkdirp the file's path
err := mkdirp.Mk(keyfile[:strings.LastIndex(keyfile, "/")], 0777)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Failed to create parent directory for key")
}
}
f, err := os.Create(keyfile)
if err != nil {
log.WithFields(log.Fields{
"error": err,
"file": keyfile,
}).Error("Failed to create file")
continue
}
defer f.Close()
log.WithFields(log.Fields{
"length": len(v),
}).Debug("Input value length")
buff := new(bytes.Buffer)
buff.Write([]byte(v))
if len(mappingConfig.Keystore) > 0 {
decryptedValue, err := gosecret.DecryptTags([]byte(v), mappingConfig.Keystore)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Failed to decrypt value")
continue
}
log.WithFields(log.Fields{
"length": len(decryptedValue),
}).Debug("Output value length")
data := string(decryptedValue)
funcs := template.FuncMap{
// Template functions
"goDecrypt": goDecryptFunc(mappingConfig.Keystore),
}
tmpl, err := template.New("decryption").Funcs(funcs).Parse(data)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Could not parse template")
continue
}
// Run the template to verify the output.
buff = new(bytes.Buffer)
err = tmpl.Execute(buff, nil)
if err != nil {
log.WithFields(log.Fields{
"error": err,
}).Error("Could not execute template")
continue
}
}
wrote, err := f.Write(buff.Bytes())
if err != nil {
log.WithFields(log.Fields{
"error": err,
"file": keyfile,
}).Error("Failed to write to file")
continue
}
log.WithFields(log.Fields{
"length": wrote,
"file": keyfile,
}).Debug("Successfully wrote value to file")
err = f.Sync()
if err != nil {
log.WithFields(log.Fields{
"error": err,
"file": keyfile,
}).Error("Failed to sync file")
}
err = f.Close()
if err != nil {
log.WithFields(log.Fields{
"error": err,
"file": keyfile,
}).Error("Failed to close file")
}
}
// Configuration changed, run our onchange command, if one was specified.
if mappingConfig.OnChange != nil {
var cmd = exec.Command(mappingConfig.OnChange[0], mappingConfig.OnChange[1:]...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
// Always wait for the forked process to exit. We may wish to revisit this, but I think
// it's the safest approach since it avoids a case where rapid key updates DOS a system
// by slurping all proc handles.
err = cmd.Run()
if err != nil {
return 111, err
}
}
// If we are only running once, close the channel on this watcher.
if config.RunOnce {
close(quitCh)
return 0, nil
}
}
}