func (p *Provisioner) getAgentTools() (*state.Tools, error) {
tools, err := agent.ReadTools(p.dataDir, version.Current)
if err != nil {
logger.Errorf("cannot read agent tools from %q", p.dataDir)
return nil, err
}
return tools, nil
}
func (t *ToolsSuite) TestReadToolsErrors(c *C) {
vers := version.MustParseBinary("1.2.3-precise-amd64")
tools, err := agent.ReadTools(t.dataDir, vers)
c.Assert(tools, IsNil)
c.Assert(err, ErrorMatches, "cannot read URL in tools directory: .*")
dir := agent.SharedToolsDir(t.dataDir, vers)
err = os.MkdirAll(dir, 0755)
c.Assert(err, IsNil)
err = ioutil.WriteFile(filepath.Join(dir, urlFile), []byte(" \t\n"), 0644)
c.Assert(err, IsNil)
tools, err = agent.ReadTools(t.dataDir, vers)
c.Assert(tools, IsNil)
c.Assert(err, ErrorMatches, "empty URL in tools directory.*")
}
// assertToolsContents asserts that the directory for the tools
// has the given contents.
func (t *ToolsSuite) assertToolsContents(c *C, tools *state.Tools, files []*testing.TarFile) {
var wantNames []string
for _, f := range files {
wantNames = append(wantNames, f.Header.Name)
}
wantNames = append(wantNames, urlFile)
dir := agent.SharedToolsDir(t.dataDir, tools.Binary)
assertDirNames(c, dir, wantNames)
assertFileContents(c, dir, urlFile, tools.URL, 0200)
for _, f := range files {
assertFileContents(c, dir, f.Header.Name, f.Contents, 0400)
}
gotTools, err := agent.ReadTools(t.dataDir, tools.Binary)
c.Assert(err, IsNil)
c.Assert(*gotTools, Equals, *tools)
}
func (u *Upgrader) run() error {
// Let the state know the version that is currently running.
currentTools, err := agent.ReadTools(u.dataDir, version.Current)
if err != nil {
// Don't abort everything because we can't find the tools directory.
// The problem should sort itself out as we will immediately
// download some more tools and upgrade.
log.Warningf("upgrader cannot read current tools: %v", err)
currentTools = &state.Tools{
Binary: version.Current,
}
}
err = u.agentState.SetAgentTools(currentTools)
if err != nil {
return err
}
// TODO(fwereade): this whole package should be ignorant of environs,
// so it shouldn't be watching environ config (and it shouldn't be
// looking in storage): we should be able to find out what to download
// from state, exactly as we do for charms.
w := u.st.WatchEnvironConfig()
defer watcher.Stop(w, &u.tomb)
// Rather than using worker.WaitForEnviron, invalid environments are
// managed explicitly so that all configuration changes are observed
// by the loop below.
var environ environs.Environ
// TODO(rog) retry downloads when they fail.
var (
download *downloader.Download
downloadTools *state.Tools
downloadDone <-chan downloader.Status
)
// If we're killed early on (probably as a result of some other
// task dying) we allow ourselves some time to try to connect to
// the state and download a new version. We return to normal
// undelayed behaviour when:
// 1) We find there's no upgrade to do.
// 2) A download fails.
tomb := delayedTomb(&u.tomb, upgraderKillDelay)
noDelay := func() {
if tomb != &u.tomb {
tomb.Kill(nil)
tomb = &u.tomb
}
}
for {
// We wait for the tools to change while we're downloading
// so that if something goes wrong (for instance a bad URL
// hangs up) another change to the proposed tools can
// potentially fix things.
select {
case cfg, ok := <-w.Changes():
if !ok {
return watcher.MustErr(w)
}
var err error
if environ == nil {
environ, err = environs.New(cfg)
if err != nil {
log.Errorf("upgrader loaded invalid initial environment configuration: %v", err)
break
}
} else {
err = environ.SetConfig(cfg)
if err != nil {
log.Warningf("upgrader loaded invalid environment configuration: %v", err)
// continue on, because the version number is still significant.
}
}
proposed, ok := cfg.AgentVersion()
if !ok {
// This shouldn't be possible; but if it happens it's no reason
// to kill this task. Just wait for the config to change again.
continue
}
if download != nil {
// There's a download in progress, stop it if we need to.
if downloadTools.Number == proposed {
// We are already downloading the requested tools.
break
}
// Tools changed. We need to stop and restart.
download.Stop()
download, downloadTools, downloadDone = nil, nil, nil
}
// TODO: major version upgrades.
if proposed.Major != version.Current.Major {
log.Errorf("major version upgrades are not supported yet")
noDelay()
break
}
if proposed == version.Current.Number {
noDelay()
break
}
required := version.Binary{
Number: proposed,
Series: version.Current.Series,
Arch: version.Current.Arch,
}
if tools, err := agent.ReadTools(u.dataDir, required); err == nil {
// The exact tools have already been downloaded, so use them.
return u.upgradeReady(currentTools, tools)
}
tools, err := environs.FindExactTools(environ, required)
if err != nil {
log.Errorf("upgrader error finding tools for %v: %v", required, err)
if !errors.IsNotFoundError(err) {
return err
}
noDelay()
// TODO(rog): poll until tools become available.
break
}
log.Infof("upgrader downloading %q", tools.URL)
download = downloader.New(tools.URL, "")
downloadTools = tools
downloadDone = download.Done()
case status := <-downloadDone:
tools := downloadTools
download, downloadTools, downloadDone = nil, nil, nil
if status.Err != nil {
log.Errorf("upgrader download of %v failed: %v", tools.Binary, status.Err)
noDelay()
break
}
err := agent.UnpackTools(u.dataDir, tools, status.File)
status.File.Close()
if err := os.Remove(status.File.Name()); err != nil {
log.Warningf("upgrader cannot remove temporary download file: %v", err)
}
if err != nil {
log.Errorf("upgrader cannot unpack %v tools: %v", tools.Binary, err)
noDelay()
break
}
return u.upgradeReady(currentTools, tools)
case <-tomb.Dying():
if download != nil {
return fmt.Errorf("upgrader aborted download of %q", downloadTools.URL)
}
return nil
}
}
panic("not reached")
}