open-nomad/client/consul_template.go
Alex Dadgar 74a736155c Always disable renew_token for CT config
This PR makes Nomad always disable token renewal even if Vault is
disabled. The problem was when there was a vault token in the
environment variable and Nomad/Vault integration was disabled, the
template runner would still try to renew the token.
2016-11-10 15:16:08 -08:00

479 lines
12 KiB
Go

package client
import (
"fmt"
"os"
"path/filepath"
"strings"
"sync"
"time"
ctconf "github.com/hashicorp/consul-template/config"
"github.com/hashicorp/consul-template/manager"
"github.com/hashicorp/consul-template/signals"
"github.com/hashicorp/consul-template/watch"
multierror "github.com/hashicorp/go-multierror"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/client/driver/env"
"github.com/hashicorp/nomad/nomad/structs"
)
const (
// hostSrcOption is the Client option that determines whether the template
// source may be from the host
hostSrcOption = "template.allow_host_source"
)
var (
// testRetryRate is used to speed up tests by setting consul-templates retry
// rate to something low
testRetryRate time.Duration = 0
)
// TaskHooks is an interface which provides hooks into the tasks life-cycle
type TaskHooks interface {
// Restart is used to restart the task
Restart(source, reason string)
// Signal is used to signal the task
Signal(source, reason string, s os.Signal) error
// UnblockStart is used to unblock the starting of the task. This should be
// called after prestart work is completed
UnblockStart(source string)
// Kill is used to kill the task because of the passed error. If fail is set
// to true, the task is marked as failed
Kill(source, reason string, fail bool)
}
// TaskTemplateManager is used to run a set of templates for a given task
type TaskTemplateManager struct {
// templates is the set of templates we are managing
templates []*structs.Template
// lookup allows looking up the set of Nomad templates by their consul-template ID
lookup map[string][]*structs.Template
// hooks is used to signal/restart the task as templates are rendered
hook TaskHooks
// runner is the consul-template runner
runner *manager.Runner
// signals is a lookup map from the string representation of a signal to its
// actual signal
signals map[string]os.Signal
// shutdownCh is used to signal and started goroutine to shutdown
shutdownCh chan struct{}
// shutdown marks whether the manager has been shutdown
shutdown bool
shutdownLock sync.Mutex
}
func NewTaskTemplateManager(hook TaskHooks, tmpls []*structs.Template,
config *config.Config, vaultToken, taskDir string,
taskEnv *env.TaskEnvironment) (*TaskTemplateManager, error) {
// Check pre-conditions
if hook == nil {
return nil, fmt.Errorf("Invalid task hook given")
} else if config == nil {
return nil, fmt.Errorf("Invalid config given")
} else if taskDir == "" {
return nil, fmt.Errorf("Invalid task directory given")
} else if taskEnv == nil {
return nil, fmt.Errorf("Invalid task environment given")
}
tm := &TaskTemplateManager{
templates: tmpls,
hook: hook,
shutdownCh: make(chan struct{}),
}
// Parse the signals that we need
for _, tmpl := range tmpls {
if tmpl.ChangeSignal == "" {
continue
}
sig, err := signals.Parse(tmpl.ChangeSignal)
if err != nil {
return nil, fmt.Errorf("Failed to parse signal %q", tmpl.ChangeSignal)
}
if tm.signals == nil {
tm.signals = make(map[string]os.Signal)
}
tm.signals[tmpl.ChangeSignal] = sig
}
// Build the consul-template runner
runner, lookup, err := templateRunner(tmpls, config, vaultToken, taskDir, taskEnv)
if err != nil {
return nil, err
}
tm.runner = runner
tm.lookup = lookup
go tm.run()
return tm, nil
}
// Stop is used to stop the consul-template runner
func (tm *TaskTemplateManager) Stop() {
tm.shutdownLock.Lock()
defer tm.shutdownLock.Unlock()
if tm.shutdown {
return
}
close(tm.shutdownCh)
tm.shutdown = true
// Stop the consul-template runner
if tm.runner != nil {
tm.runner.Stop()
}
}
// run is the long lived loop that handles errors and templates being rendered
func (tm *TaskTemplateManager) run() {
// Runner is nil if there is no templates
if tm.runner == nil {
// Unblock the start if there is nothing to do
tm.hook.UnblockStart("consul-template")
return
}
// Start the runner
go tm.runner.Start()
// Track when they have all been rendered so we don't signal the task for
// any render event before hand
var allRenderedTime time.Time
// Handle the first rendering
// Wait till all the templates have been rendered
WAIT:
for {
select {
case <-tm.shutdownCh:
return
case err, ok := <-tm.runner.ErrCh:
if !ok {
continue
}
tm.hook.Kill("consul-template", err.Error(), true)
case <-tm.runner.TemplateRenderedCh():
// A template has been rendered, figure out what to do
events := tm.runner.RenderEvents()
// Not all templates have been rendered yet
if len(events) < len(tm.lookup) {
continue
}
for _, event := range events {
// This template hasn't been rendered
if event.LastWouldRender.IsZero() {
continue WAIT
}
}
break WAIT
}
}
allRenderedTime = time.Now()
tm.hook.UnblockStart("consul-template")
// If all our templates are change mode no-op, then we can exit here
if tm.allTemplatesNoop() {
return
}
// A lookup for the last time the template was handled
numTemplates := len(tm.templates)
handledRenders := make(map[string]time.Time, numTemplates)
for {
select {
case <-tm.shutdownCh:
return
case err, ok := <-tm.runner.ErrCh:
if !ok {
continue
}
tm.hook.Kill("consul-template", err.Error(), true)
case <-tm.runner.TemplateRenderedCh():
// A template has been rendered, figure out what to do
var handling []string
signals := make(map[string]struct{})
restart := false
var splay time.Duration
events := tm.runner.RenderEvents()
for id, event := range events {
// First time through
if allRenderedTime.After(event.LastDidRender) || allRenderedTime.Equal(event.LastDidRender) {
handledRenders[id] = allRenderedTime
continue
}
// We have already handled this one
if htime := handledRenders[id]; htime.After(event.LastDidRender) || htime.Equal(event.LastDidRender) {
continue
}
// Lookup the template and determine what to do
tmpls, ok := tm.lookup[id]
if !ok {
tm.hook.Kill("consul-template", fmt.Sprintf("consul-template runner returned unknown template id %q", id), true)
return
}
for _, tmpl := range tmpls {
switch tmpl.ChangeMode {
case structs.TemplateChangeModeSignal:
signals[tmpl.ChangeSignal] = struct{}{}
case structs.TemplateChangeModeRestart:
restart = true
case structs.TemplateChangeModeNoop:
continue
}
if tmpl.Splay > splay {
splay = tmpl.Splay
}
}
handling = append(handling, id)
}
if restart || len(signals) != 0 {
if splay != 0 {
select {
case <-time.After(time.Duration(splay)):
case <-tm.shutdownCh:
return
}
}
// Update handle time
for _, id := range handling {
handledRenders[id] = events[id].LastDidRender
}
if restart {
tm.hook.Restart("consul-template", "template with change_mode restart re-rendered")
} else if len(signals) != 0 {
var mErr multierror.Error
for signal := range signals {
err := tm.hook.Signal("consul-template", "template re-rendered", tm.signals[signal])
if err != nil {
multierror.Append(&mErr, err)
}
}
if err := mErr.ErrorOrNil(); err != nil {
flat := make([]os.Signal, 0, len(signals))
for signal := range signals {
flat = append(flat, tm.signals[signal])
}
tm.hook.Kill("consul-template", fmt.Sprintf("Sending signals %v failed: %v", flat, err), true)
}
}
}
}
}
}
// allTemplatesNoop returns whether all the managed templates have change mode noop.
func (tm *TaskTemplateManager) allTemplatesNoop() bool {
for _, tmpl := range tm.templates {
if tmpl.ChangeMode != structs.TemplateChangeModeNoop {
return false
}
}
return true
}
// templateRunner returns a consul-template runner for the given templates and a
// lookup by destination to the template. If no templates are given, a nil
// template runner and lookup is returned.
func templateRunner(tmpls []*structs.Template, config *config.Config,
vaultToken, taskDir string, taskEnv *env.TaskEnvironment) (
*manager.Runner, map[string][]*structs.Template, error) {
if len(tmpls) == 0 {
return nil, nil, nil
}
runnerConfig, err := runnerConfig(config, vaultToken)
if err != nil {
return nil, nil, err
}
// Parse the templates
allowAbs := config.ReadBoolDefault(hostSrcOption, true)
ctmplMapping, err := parseTemplateConfigs(tmpls, taskDir, taskEnv, allowAbs)
if err != nil {
return nil, nil, err
}
// Set the config
flat := make([]*ctconf.ConfigTemplate, 0, len(ctmplMapping))
for ctmpl := range ctmplMapping {
local := ctmpl
flat = append(flat, &local)
}
runnerConfig.ConfigTemplates = flat
runner, err := manager.NewRunner(runnerConfig, false, false)
if err != nil {
return nil, nil, err
}
// Build the lookup
idMap := runner.ConfigTemplateMapping()
lookup := make(map[string][]*structs.Template, len(idMap))
for id, ctmpls := range idMap {
for _, ctmpl := range ctmpls {
templates := lookup[id]
templates = append(templates, ctmplMapping[ctmpl])
lookup[id] = templates
}
}
return runner, lookup, nil
}
// parseTemplateConfigs converts the tasks templates into consul-templates
func parseTemplateConfigs(tmpls []*structs.Template, taskDir string,
taskEnv *env.TaskEnvironment, allowAbs bool) (map[ctconf.ConfigTemplate]*structs.Template, error) {
// Build the task environment
// TODO Should be able to inject the Nomad env vars into Consul-template for
// rendering
taskEnv.Build()
ctmpls := make(map[ctconf.ConfigTemplate]*structs.Template, len(tmpls))
for _, tmpl := range tmpls {
var src, dest string
if tmpl.SourcePath != "" {
if filepath.IsAbs(tmpl.SourcePath) {
if !allowAbs {
return nil, fmt.Errorf("Specifying absolute template paths disallowed by client config: %q", tmpl.SourcePath)
}
src = tmpl.SourcePath
} else {
src = filepath.Join(taskDir, taskEnv.ReplaceEnv(tmpl.SourcePath))
}
}
if tmpl.DestPath != "" {
dest = filepath.Join(taskDir, taskEnv.ReplaceEnv(tmpl.DestPath))
}
ct := ctconf.ConfigTemplate{
Source: src,
Destination: dest,
EmbeddedTemplate: tmpl.EmbeddedTmpl,
Perms: ctconf.DefaultFilePerms,
Wait: &watch.Wait{},
}
ctmpls[ct] = tmpl
}
return ctmpls, nil
}
// runnerConfig returns a consul-template runner configuration, setting the
// Vault and Consul configurations based on the clients configs.
func runnerConfig(config *config.Config, vaultToken string) (*ctconf.Config, error) {
conf := &ctconf.Config{}
set := func(keys []string) {
for _, k := range keys {
conf.Set(k)
}
}
if testRetryRate != 0 {
conf.Retry = testRetryRate
conf.Set("retry")
}
// Setup the Consul config
if config.ConsulConfig != nil {
conf.Consul = config.ConsulConfig.Addr
conf.Token = config.ConsulConfig.Token
set([]string{"consul", "token"})
if config.ConsulConfig.EnableSSL {
conf.SSL = &ctconf.SSLConfig{
Enabled: true,
Verify: config.ConsulConfig.VerifySSL,
Cert: config.ConsulConfig.CertFile,
Key: config.ConsulConfig.KeyFile,
CaCert: config.ConsulConfig.CAFile,
}
set([]string{"ssl", "ssl.enabled", "ssl.verify", "ssl.cert", "ssl.key", "ssl.ca_cert"})
}
if config.ConsulConfig.Auth != "" {
parts := strings.SplitN(config.ConsulConfig.Auth, ":", 2)
if len(parts) != 2 {
return nil, fmt.Errorf("Failed to parse Consul Auth config")
}
conf.Auth = &ctconf.AuthConfig{
Enabled: true,
Username: parts[0],
Password: parts[1],
}
set([]string{"auth", "auth.username", "auth.password", "auth.enabled"})
}
}
// Setup the Vault config
// Always set these to ensure nothing is picked up from the environment
conf.Vault = &ctconf.VaultConfig{
RenewToken: false,
}
set([]string{"vault", "vault.token", "vault.renew_token"})
if config.VaultConfig != nil && config.VaultConfig.IsEnabled() {
conf.Vault.Address = config.VaultConfig.Addr
conf.Vault.Token = vaultToken
set([]string{"vault.address"})
if strings.HasPrefix(config.VaultConfig.Addr, "https") || config.VaultConfig.TLSCertFile != "" {
verify := config.VaultConfig.TLSSkipVerify == nil || !*config.VaultConfig.TLSSkipVerify
conf.Vault.SSL = &ctconf.SSLConfig{
Enabled: true,
Verify: !verify,
Cert: config.VaultConfig.TLSCertFile,
Key: config.VaultConfig.TLSKeyFile,
CaCert: config.VaultConfig.TLSCaFile,
CaPath: config.VaultConfig.TLSCaPath,
}
set([]string{"vault.ssl", "vault.ssl.enabled", "vault.ssl.verify",
"vault.ssl.cert", "vault.ssl.key", "vault.ssl.ca_cert"})
}
}
return conf, nil
}