// Wrapper for minicli.ProcessCommand for commands that use meshage.
// Specifically, for `mesh send all ...`, runs the subcommand locally and
// across meshage, combining the results from the two channels into a single
// channel. This is useful if you want to get the output of a command from all
// nodes in the cluster without having to run a command locally and over
// meshage.
func runCommandGlobally(cmd *minicli.Command) chan minicli.Responses {
// Keep the original CLI input
original := cmd.Original
record := cmd.Record
cmd, err := minicli.Compilef("mesh send %s .record %t %s", Wildcard, record, original)
if err != nil {
log.Fatal("cannot run `%v` globally -- %v", original, err)
}
cmd.Record = record
cmdLock.Lock()
var wg sync.WaitGroup
out := make(chan minicli.Responses)
cmd, err = cliPreprocessor(cmd)
if err != nil {
log.Errorln(err)
out <- minicli.Responses{
&minicli.Response{
Host: hostname,
Error: err.Error(),
},
}
close(out)
return out
}
// Run the command (should be `mesh send all ...` and the subcommand which
// should run locally).
ins := []chan minicli.Responses{
minicli.ProcessCommand(cmd),
minicli.ProcessCommand(cmd.Subcommand),
}
// De-mux ins into out
for _, in := range ins {
wg.Add(1)
go func(in chan minicli.Responses) {
defer wg.Done()
for v := range in {
out <- v
}
}(in)
}
// Wait until everything has been read before closing the chan and
// releasing the lock.
go func() {
defer cmdLock.Unlock()
defer close(out)
wg.Wait()
}()
return out
}
// runCommands is RunCommands without locking cmdLock.
func runCommands(cmd ...*minicli.Command) <-chan minicli.Responses {
out := make(chan minicli.Responses)
// Preprocess all the commands so that if there's an error, we haven't
// already started to run some of the commands.
for i := range cmd {
if err := cliPreprocessor(cmd[i]); err != nil {
log.Errorln(err)
// Send the error from a separate goroutine because nothing will
// receive from this channel until we return. Otherwise, we will
// cause a deadlock.
go func() {
out <- errResp(err)
close(out)
}()
return out
}
}
// Completed preprocessing run commands serially and forward all the
// responses to out
go func() {
defer close(out)
for _, c := range cmd {
forward(minicli.ProcessCommand(c), out)
}
}()
return out
}
// Wrapper for minicli.ProcessCommand. Ensures that the command execution lock
// is acquired before running the command.
func runCommand(cmd *minicli.Command) chan minicli.Responses {
cmdLock.Lock()
// Forward the responses and unlock when all are passed through
localChan := make(chan minicli.Responses)
go func() {
defer cmdLock.Unlock()
cmd, err := cliPreprocessor(cmd)
if err != nil {
log.Errorln(err)
localChan <- minicli.Responses{
&minicli.Response{
Host: hostname,
Error: err.Error(),
},
}
close(localChan)
return
}
for resp := range minicli.ProcessCommand(cmd) {
localChan <- resp
}
close(localChan)
}()
return localChan
}
func cliRead(c *minicli.Command, respChan chan minicli.Responses) {
resp := &minicli.Response{Host: hostname}
file, err := os.Open(c.StringArgs["file"])
if err != nil {
resp.Error = err.Error()
respChan <- minicli.Responses{resp}
return
}
defer file.Close()
scanner := bufio.NewScanner(file)
for scanner.Scan() {
var cmd *minicli.Command
command := scanner.Text()
log.Debug("read command: %v", command) // commands don't have their newlines removed
cmd, err = minicli.CompileCommand(command)
if err != nil {
break
}
// No command was returned, must have been a blank line or a comment
// line. Either way, don't try to run a nil command.
if cmd == nil {
continue
}
// HAX: Make sure we don't have a recursive read command
if hasCommand(cmd, "read") {
err = errors.New("cannot run nested `read` commands")
break
}
for resp := range minicli.ProcessCommand(cmd, true) {
respChan <- resp
// Stop processing at the first error if there is one response.
// TODO: What should we do if the command was mesh send and there
// is a mixture of success and failure?
if len(resp) == 1 && resp[0].Error != "" {
break
}
}
}
if err != nil {
resp.Error = err.Error()
respChan <- minicli.Responses{resp}
}
if err := scanner.Err(); err != nil {
resp.Error = err.Error()
respChan <- minicli.Responses{resp}
}
}
func main() {
flag.Parse()
logSetup()
// register CLI handlers
for i := range cliHandlers {
err := minicli.Register(&cliHandlers[i])
if err != nil {
log.Fatal("invalid handler, `%v` -- %v", cliHandlers[i].HelpShort, err)
}
}
var err error
hostname, err = os.Hostname()
if err != nil {
log.Fatal("unable to get hostname: %v", hostname)
}
rond, err = ron.NewServer(*f_port, *f_path)
if err != nil {
log.Fatal("unable to create server: %v", err)
}
for {
line, err := goreadline.Readline("rond$ ", true)
if err != nil {
return
}
command := string(line)
log.Debug("got from stdin: `%s`", line)
cmd, err := minicli.Compile(command)
if err != nil {
log.Error("%v", err)
continue
}
// No command was returned, must have been a blank line or a comment
// line. Either way, don't try to run a nil command.
if cmd == nil {
continue
}
for resp := range minicli.ProcessCommand(cmd) {
minipager.DefaultPager.Page(resp.String())
errs := resp.Error()
if errs != "" {
fmt.Fprintln(os.Stderr, errs)
}
}
}
}
// Wrapper for minicli.ProcessCommand for commands that use meshage.
// Specifically, for `mesh send all ...`, runs the subcommand locally and
// across meshage, combining the results from the two channels into a single
// channel. This is useful if you want to get the output of a command from all
// nodes in the cluster without having to run a command locally and over
// meshage.
func runCommandGlobally(cmd *minicli.Command, record bool) chan minicli.Responses {
cmdStr := fmt.Sprintf("mesh send %s %s", Wildcard, cmd.Original)
cmd, err := minicli.CompileCommand(cmdStr)
if err != nil {
log.Fatal("cannot run `%v` globally -- %v", cmd.Original, err)
}
cmdLock.Lock()
defer cmdLock.Unlock()
var wg sync.WaitGroup
out := make(chan minicli.Responses)
// Run the command (should be `mesh send all ...` and the subcommand which
// should run locally).
ins := []chan minicli.Responses{
minicli.ProcessCommand(cmd, record),
minicli.ProcessCommand(cmd.Subcommand, record),
}
// De-mux ins into out
for _, in := range ins {
wg.Add(1)
go func(in chan minicli.Responses) {
defer wg.Done()
for v := range in {
out <- v
}
}(in)
}
// Wait until everything has been read before closing out
go func() {
wg.Wait()
close(out)
}()
return out
}
// Wrapper for minicli.ProcessCommand. Ensures that the command execution lock
// is acquired before running the command.
func runCommand(cmd *minicli.Command) chan minicli.Responses {
cmdLock.Lock()
// Forward the responses and unlock when all are passed through
localChan := make(chan minicli.Responses)
go func() {
defer cmdLock.Unlock()
for resp := range minicli.ProcessCommand(cmd) {
localChan <- resp
}
close(localChan)
}()
return localChan
}
// Wrapper for minicli.ProcessCommand. Ensures that the command execution lock
// is acquired before running the command.
func runCommand(cmd *minicli.Command, record bool) chan minicli.Responses {
cmdLock.Lock()
defer cmdLock.Unlock()
return minicli.ProcessCommand(cmd, record)
}
// dot returns a graphviz 'dotfile' string representing the experiment topology
// from the perspective of this node.
func cliDot(c *minicli.Command) *minicli.Response {
resp := &minicli.Response{Host: hostname}
// Create the file before running any commands incase there is an error
fout, err := os.Create(c.StringArgs["filename"])
if err != nil {
resp.Error = err.Error()
return resp
}
defer fout.Close()
// TODO: Rewrite to use runCommandGlobally
cmd := minicli.MustCompile(".columns host,name,id,ip,ip6,state,vlan vm info")
writer := bufio.NewWriter(fout)
fmt.Fprintln(writer, "graph minimega {")
fmt.Fprintln(writer, `size=\"8,11\";`)
fmt.Fprintln(writer, "overlap=false;")
//fmt.Fprintf(fout, "Legend [shape=box, shape=plaintext, label=\"total=%d\"];\n", len(n.effectiveNetwork))
var expVms []*dotVM
// Get info from local hosts by invoking command directly
for resp := range minicli.ProcessCommand(cmd, false) {
expVms = append(expVms, dotProcessInfo(resp)...)
}
// Get info from remote hosts over meshage
remoteRespChan := make(chan minicli.Responses)
go func() {
meshageBroadcast(cmd, remoteRespChan)
close(remoteRespChan)
}()
for resp := range remoteRespChan {
expVms = append(expVms, dotProcessInfo(resp)...)
}
vlans := make(map[string]bool)
for _, v := range expVms {
color := stateToColor[v.State]
fmt.Fprintf(writer, "%s [style=filled, color=%s];\n", v.Text, color)
for _, c := range v.Vlans {
fmt.Fprintf(writer, "%s -- %s\n", v.Text, c)
vlans[c] = true
}
}
for k, _ := range vlans {
fmt.Fprintf(writer, "%s;\n", k)
}
fmt.Fprint(writer, "}")
err = writer.Flush()
if err != nil {
resp.Error = err.Error()
}
return resp
}