Add exec type and fix up a few other things
* Add exec type * Switch erroneous use of fmt to log instead * Check for edge existence for safety before using * Avoid recalling etcd channel maker * Clean up logging output
This commit is contained in:
James Shubin
333
exec.go
Normal file
333
exec.go
Normal file
@@ -0,0 +1,333 @@
|
||||
// Mgmt
|
||||
// Copyright (C) 2013-2016+ James Shubin and the project contributors
|
||||
// Written by James Shubin <james@shubin.ca> and the project contributors
|
||||
//
|
||||
// This program is free software: you can redistribute it and/or modify
|
||||
// it under the terms of the GNU Affero General Public License as published by
|
||||
// the Free Software Foundation, either version 3 of the License, or
|
||||
// (at your option) any later version.
|
||||
//
|
||||
// This program is distributed in the hope that it will be useful,
|
||||
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
// GNU Affero General Public License for more details.
|
||||
//
|
||||
// You should have received a copy of the GNU Affero General Public License
|
||||
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
package main
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"bytes"
|
||||
"log"
|
||||
"os/exec"
|
||||
"strings"
|
||||
)
|
||||
|
||||
type ExecType struct {
|
||||
BaseType `yaml:",inline"`
|
||||
State string `yaml:"state"` // state: exists/present?, absent, (undefined?)
|
||||
Cmd string `yaml:"cmd"` // the command to run
|
||||
Shell string `yaml:"shell"` // the (optional) shell to use to run the cmd
|
||||
Timeout int `yaml:"timeout"` // the cmd timeout in seconds
|
||||
WatchCmd string `yaml:"watchcmd"` // the watch command to run
|
||||
WatchShell string `yaml:"watchshell"` // the (optional) shell to use to run the watch cmd
|
||||
IfCmd string `yaml:"ifcmd"` // the if command to run
|
||||
IfShell string `yaml:"ifshell"` // the (optional) shell to use to run the if cmd
|
||||
PollInt int `yaml:"pollint"` // the poll interval for the ifcmd
|
||||
isStateOK bool // whether the state is okay based on events or not
|
||||
}
|
||||
|
||||
func NewExecType(name, cmd, shell string, timeout int, watchcmd, watchshell, ifcmd, ifshell string, pollint int, state string) *ExecType {
|
||||
// FIXME if path = nil, path = name ...
|
||||
return &ExecType{
|
||||
BaseType: BaseType{
|
||||
Name: name,
|
||||
events: make(chan Event),
|
||||
vertex: nil,
|
||||
},
|
||||
Cmd: cmd,
|
||||
Shell: shell,
|
||||
Timeout: timeout,
|
||||
WatchCmd: watchcmd,
|
||||
WatchShell: watchshell,
|
||||
IfCmd: ifcmd,
|
||||
IfShell: ifshell,
|
||||
PollInt: pollint,
|
||||
State: state,
|
||||
}
|
||||
}
|
||||
|
||||
func (obj *ExecType) GetType() string {
|
||||
return "Exec"
|
||||
}
|
||||
|
||||
// validate if the params passed in are valid data
|
||||
// FIXME: where should this get called ?
|
||||
func (obj *ExecType) Validate() bool {
|
||||
if obj.Cmd == "" { // this is the only thing that is really required
|
||||
return false
|
||||
}
|
||||
|
||||
// if we have a watch command, then we don't poll with the if command!
|
||||
if obj.WatchCmd != "" && obj.PollInt > 0 {
|
||||
return false
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
// wraps the scanner output in a channel
|
||||
func (obj *ExecType) BufioChanScanner(scanner *bufio.Scanner) (chan string, chan error) {
|
||||
ch, errch := make(chan string), make(chan error)
|
||||
go func() {
|
||||
for scanner.Scan() {
|
||||
ch <- scanner.Text() // blocks here ?
|
||||
if e := scanner.Err(); e != nil {
|
||||
errch <- e // send any misc errors we encounter
|
||||
//break // TODO ?
|
||||
}
|
||||
}
|
||||
close(ch)
|
||||
errch <- scanner.Err() // eof or some err
|
||||
close(errch)
|
||||
}()
|
||||
return ch, errch
|
||||
}
|
||||
|
||||
// Exec watcher
|
||||
func (obj *ExecType) Watch() {
|
||||
if obj.IsWatching() {
|
||||
return
|
||||
}
|
||||
obj.SetWatching(true)
|
||||
defer obj.SetWatching(false)
|
||||
|
||||
var send = false // send event?
|
||||
bufioch, errch := make(chan string), make(chan error)
|
||||
//vertex := obj.GetVertex() // stored with SetVertex
|
||||
|
||||
if obj.WatchCmd != "" {
|
||||
var cmdName string
|
||||
var cmdArgs []string
|
||||
if obj.WatchShell == "" {
|
||||
// call without a shell
|
||||
// FIXME: are there still whitespace splitting issues?
|
||||
split := strings.Fields(obj.WatchCmd)
|
||||
cmdName = split[0]
|
||||
//d, _ := os.Getwd() // TODO: how does this ever error ?
|
||||
//cmdName = path.Join(d, cmdName)
|
||||
cmdArgs = split[1:len(split)]
|
||||
} else {
|
||||
cmdName = obj.Shell // usually bash, or sh
|
||||
cmdArgs = []string{"-c", obj.WatchCmd}
|
||||
}
|
||||
cmd := exec.Command(cmdName, cmdArgs...)
|
||||
//cmd.Dir = "" // look for program in pwd ?
|
||||
|
||||
cmdReader, err := cmd.StdoutPipe()
|
||||
if err != nil {
|
||||
log.Printf("%v[%v]: Error creating StdoutPipe for Cmd: %v", obj.GetType(), obj.GetName(), err)
|
||||
log.Fatal(err) // XXX: how should we handle errors?
|
||||
}
|
||||
scanner := bufio.NewScanner(cmdReader)
|
||||
|
||||
defer cmd.Wait() // XXX: is this necessary?
|
||||
defer cmd.Process.Kill() // TODO: is this necessary?
|
||||
if err := cmd.Start(); err != nil {
|
||||
log.Printf("%v[%v]: Error starting Cmd: %v", obj.GetType(), obj.GetName(), err)
|
||||
log.Fatal(err) // XXX: how should we handle errors?
|
||||
}
|
||||
|
||||
bufioch, errch = obj.BufioChanScanner(scanner)
|
||||
}
|
||||
|
||||
for {
|
||||
select {
|
||||
case text := <-bufioch:
|
||||
obj.SetState(typeNil)
|
||||
|
||||
// each time we get a line of output, we loop!
|
||||
log.Printf("%v[%v]: Watch output: %s", obj.GetType(), obj.GetName(), text)
|
||||
if text != "" {
|
||||
send = true
|
||||
}
|
||||
|
||||
case err := <-errch:
|
||||
obj.SetState(typeNil) // XXX ?
|
||||
if err == nil { // EOF
|
||||
// FIXME: add an "if watch command ends/crashes"
|
||||
// restart or generate error option
|
||||
log.Printf("%v[%v]: Reached EOF", obj.GetType(), obj.GetName())
|
||||
return
|
||||
}
|
||||
log.Printf("%v[%v]: Error reading input?: %v", obj.GetType(), obj.GetName(), err)
|
||||
log.Fatal(err)
|
||||
// XXX: how should we handle errors?
|
||||
|
||||
case event := <-obj.events:
|
||||
obj.SetState(typeNil)
|
||||
if ok := obj.ReadEvent(&event); !ok {
|
||||
return // exit
|
||||
}
|
||||
send = true
|
||||
|
||||
case _ = <-TimeAfterOrBlock(obj.ctimeout):
|
||||
obj.SetState(typeConvergedTimeout)
|
||||
obj.converged <- true
|
||||
continue
|
||||
}
|
||||
|
||||
// do all our event sending all together to avoid duplicate msgs
|
||||
if send {
|
||||
send = false
|
||||
obj.isStateOK = false // something made state dirty
|
||||
obj.Process(obj) // XXX: rename this function
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// TODO: expand the IfCmd to be a list of commands
|
||||
func (obj *ExecType) StateOK() bool {
|
||||
|
||||
// if there is a watch command, but no if command, run based on state
|
||||
if b := obj.isStateOK; obj.WatchCmd != "" && obj.IfCmd == "" {
|
||||
obj.isStateOK = true // reset
|
||||
//if !obj.isStateOK { obj.isStateOK = true; return false }
|
||||
return b
|
||||
|
||||
// if there is no watcher, but there is an onlyif check, run it to see
|
||||
} else if obj.IfCmd != "" { // && obj.WatchCmd == ""
|
||||
// there is a watcher, but there is also an if command
|
||||
//} else if obj.IfCmd != "" && obj.WatchCmd != "" {
|
||||
|
||||
if obj.PollInt > 0 { // && obj.WatchCmd == ""
|
||||
// XXX have the Watch() command output onlyif poll events...
|
||||
// XXX we can optimize by saving those results for returning here
|
||||
// return XXX
|
||||
}
|
||||
|
||||
var cmdName string
|
||||
var cmdArgs []string
|
||||
if obj.IfShell == "" {
|
||||
// call without a shell
|
||||
// FIXME: are there still whitespace splitting issues?
|
||||
split := strings.Fields(obj.IfCmd)
|
||||
cmdName = split[0]
|
||||
//d, _ := os.Getwd() // TODO: how does this ever error ?
|
||||
//cmdName = path.Join(d, cmdName)
|
||||
cmdArgs = split[1:len(split)]
|
||||
} else {
|
||||
cmdName = obj.IfShell // usually bash, or sh
|
||||
cmdArgs = []string{"-c", obj.IfCmd}
|
||||
}
|
||||
err := exec.Command(cmdName, cmdArgs...).Run()
|
||||
if err != nil {
|
||||
// TODO: check exit value
|
||||
return true // don't run
|
||||
}
|
||||
return false // just run
|
||||
|
||||
// if there is no watcher and no onlyif check, assume we should run
|
||||
} else { // if obj.WatchCmd == "" && obj.IfCmd == "" {
|
||||
return false // just run
|
||||
}
|
||||
}
|
||||
|
||||
func (obj *ExecType) Apply() bool {
|
||||
log.Printf("%v[%v]: Apply", obj.GetType(), obj.GetName())
|
||||
var cmdName string
|
||||
var cmdArgs []string
|
||||
if obj.Shell == "" {
|
||||
// call without a shell
|
||||
// FIXME: are there still whitespace splitting issues?
|
||||
// TODO: we could make the split character user selectable...!
|
||||
split := strings.Fields(obj.Cmd)
|
||||
cmdName = split[0]
|
||||
//d, _ := os.Getwd() // TODO: how does this ever error ?
|
||||
//cmdName = path.Join(d, cmdName)
|
||||
cmdArgs = split[1:len(split)]
|
||||
} else {
|
||||
cmdName = obj.Shell // usually bash, or sh
|
||||
cmdArgs = []string{"-c", obj.Cmd}
|
||||
}
|
||||
cmd := exec.Command(cmdName, cmdArgs...)
|
||||
//cmd.Dir = "" // look for program in pwd ?
|
||||
var out bytes.Buffer
|
||||
cmd.Stdout = &out
|
||||
|
||||
if err := cmd.Start(); err != nil {
|
||||
log.Printf("%v[%v]: Error starting Cmd: %v", obj.GetType(), obj.GetName(), err)
|
||||
return false
|
||||
}
|
||||
|
||||
timeout := obj.Timeout
|
||||
if timeout == 0 { // zero timeout means no timer, so disable it
|
||||
timeout = -1
|
||||
}
|
||||
done := make(chan error)
|
||||
go func() { done <- cmd.Wait() }()
|
||||
|
||||
select {
|
||||
case err := <-done:
|
||||
if err != nil {
|
||||
log.Printf("%v[%v]: Error waiting for Cmd: %v", obj.GetType(), obj.GetName(), err)
|
||||
return false
|
||||
}
|
||||
|
||||
case <-TimeAfterOrBlock(timeout):
|
||||
log.Printf("%v[%v]: Timeout waiting for Cmd", obj.GetType(), obj.GetName())
|
||||
//cmd.Process.Kill() // TODO: is this necessary?
|
||||
return false
|
||||
}
|
||||
|
||||
// TODO: if we printed the stdout while the command is running, this
|
||||
// would be nice, but it would require terminal log output that doesn't
|
||||
// interleave all the parallel parts which would mix it all up...
|
||||
if s := out.String(); s == "" {
|
||||
log.Printf("Exec[%v]: Command output is empty!", obj.Name)
|
||||
} else {
|
||||
log.Printf("Exec[%v]: Command output is:", obj.Name)
|
||||
log.Printf(out.String())
|
||||
}
|
||||
// XXX: return based on exit value!!
|
||||
return true
|
||||
}
|
||||
|
||||
func (obj *ExecType) Compare(typ Type) bool {
|
||||
switch typ.(type) {
|
||||
case *ExecType:
|
||||
typ := typ.(*ExecType)
|
||||
if obj.Name != typ.Name {
|
||||
return false
|
||||
}
|
||||
if obj.Cmd != typ.Cmd {
|
||||
return false
|
||||
}
|
||||
if obj.Shell != typ.Shell {
|
||||
return false
|
||||
}
|
||||
if obj.Timeout != typ.Timeout {
|
||||
return false
|
||||
}
|
||||
if obj.WatchCmd != typ.WatchCmd {
|
||||
return false
|
||||
}
|
||||
if obj.WatchShell != typ.WatchShell {
|
||||
return false
|
||||
}
|
||||
if obj.IfCmd != typ.IfCmd {
|
||||
return false
|
||||
}
|
||||
if obj.PollInt != typ.PollInt {
|
||||
return false
|
||||
}
|
||||
if obj.State != typ.State {
|
||||
return false
|
||||
}
|
||||
default:
|
||||
return false
|
||||
}
|
||||
return true
|
||||
}
|
||||
Reference in New Issue
Block a user