98 lines
2.1 KiB
Go
98 lines
2.1 KiB
Go
// Copyright (c) HashiCorp, Inc.
|
|
// SPDX-License-Identifier: MPL-2.0
|
|
|
|
package pipebootstrap
|
|
|
|
import (
|
|
"bytes"
|
|
"flag"
|
|
"os"
|
|
"time"
|
|
|
|
"github.com/mitchellh/cli"
|
|
|
|
"github.com/hashicorp/consul/command/flags"
|
|
)
|
|
|
|
func New(ui cli.Ui) *cmd {
|
|
c := &cmd{UI: ui}
|
|
c.init()
|
|
return c
|
|
}
|
|
|
|
type cmd struct {
|
|
UI cli.Ui
|
|
flags *flag.FlagSet
|
|
help string
|
|
}
|
|
|
|
func (c *cmd) init() {
|
|
c.help = flags.Usage(help, c.flags)
|
|
}
|
|
|
|
func (c *cmd) Run(args []string) int {
|
|
// Read from STDIN, write to the named pipe provided in the only positional arg
|
|
if len(args) != 1 {
|
|
c.UI.Error("Expecting named pipe path as argument")
|
|
return 1
|
|
}
|
|
|
|
// This should never be alive for very long. In case bad things happen and
|
|
// Envoy never starts limit how long we live before just exiting so we can't
|
|
// accumulate tons of these zombie children.
|
|
time.AfterFunc(10*time.Second, func() {
|
|
// Force cleanup
|
|
os.RemoveAll(args[0])
|
|
os.Exit(99)
|
|
})
|
|
|
|
var buf bytes.Buffer
|
|
if _, err := buf.ReadFrom(os.Stdin); err != nil {
|
|
c.UI.Error(err.Error())
|
|
return 1
|
|
}
|
|
|
|
// WRONLY is very important here - the open() call will block until there is a
|
|
// reader (Envoy) if we open it with RDWR though that counts as an opener and
|
|
// we will just send the data to ourselves as the first opener and so only
|
|
// valid reader.
|
|
f, err := os.OpenFile(args[0], os.O_WRONLY|os.O_APPEND, 0700)
|
|
if err != nil {
|
|
c.UI.Error(err.Error())
|
|
return 1
|
|
}
|
|
|
|
if _, err := buf.WriteTo(f); err != nil {
|
|
c.UI.Error(err.Error())
|
|
return 1
|
|
}
|
|
|
|
if err = f.Close(); err != nil {
|
|
c.UI.Error(err.Error())
|
|
return 1
|
|
}
|
|
|
|
// Use Warn to send to stderr, because all logs should go to stderr.
|
|
c.UI.Warn("Bootstrap sent, unlinking named pipe")
|
|
|
|
// Removed named pipe now we sent it. Even if Envoy has not yet read it, we
|
|
// know it has opened it and has the file descriptor since our write above
|
|
// will block until there is a reader.
|
|
os.RemoveAll(args[0])
|
|
|
|
return 0
|
|
}
|
|
|
|
func (c *cmd) Synopsis() string {
|
|
return synopsis
|
|
}
|
|
|
|
func (c *cmd) Help() string {
|
|
return c.help
|
|
}
|
|
|
|
const synopsis = "Internal shim for delivering Envoy bootstrap without writing to file system"
|
|
const help = `
|
|
Usage: should only be used internally by consul connect envoy
|
|
`
|