// runHook executes the supplied hook.Info in an appropriate hook context. If
// the hook itself fails to execute, it returns errHookFailed.
func (u *Uniter) runHook(hi hook.Info) (err error) {
// Prepare context.
if err = hi.Validate(); err != nil {
return err
}
hookName := string(hi.Kind)
relationId := -1
if hi.Kind.IsRelation() {
relationId = hi.RelationId
if hookName, err = u.relationers[relationId].PrepareHook(hi); err != nil {
return err
}
}
hctxId := fmt.Sprintf("%s:%s:%d", u.unit.Name(), hookName, u.rand.Int63())
lockMessage := fmt.Sprintf("%s: running hook %q", u.unit.Name(), hookName)
if err = u.acquireHookLock(lockMessage); err != nil {
return err
}
defer u.hookLock.Unlock()
hctx, err := u.getHookContext(hctxId, relationId, hi.RemoteUnit)
if err != nil {
return err
}
srv, socketPath, err := u.startJujucServer(hctx)
if err != nil {
return err
}
defer srv.Close()
// Run the hook.
if err := u.writeState(RunHook, Pending, &hi, nil); err != nil {
return err
}
logger.Infof("running %q hook", hookName)
ranHook := true
err = hctx.RunHook(hookName, u.charmPath, u.toolsDir, socketPath)
if IsMissingHookError(err) {
ranHook = false
} else if err != nil {
logger.Errorf("hook failed: %s", err)
u.notifyHookFailed(hookName, hctx)
return errHookFailed
}
if err := u.writeState(RunHook, Done, &hi, nil); err != nil {
return err
}
if ranHook {
logger.Infof("ran %q hook", hookName)
u.notifyHookCompleted(hookName, hctx)
} else {
logger.Infof("skipped %q hook (missing)", hookName)
}
return u.commitHook(hi)
}
func (s *RelationerSuite) assertHook(c *gc.C, expect hook.Info) {
s.BackingState.StartSync()
// We must ensure the local state dir exists first.
c.Assert(s.dir.Ensure(), gc.IsNil)
select {
case hi, ok := <-s.hooks:
c.Assert(ok, gc.Equals, true)
expect.ChangeVersion = hi.ChangeVersion
c.Assert(hi, gc.DeepEquals, expect)
c.Assert(s.dir.Write(hi), gc.Equals, nil)
case <-time.After(coretesting.LongWait):
c.Fatalf("timed out waiting for %#v", expect)
}
}
// deploy deploys the supplied charm URL, and sets follow-up hook operation state
// as indicated by reason.
func (u *Uniter) deploy(curl *corecharm.URL, reason Op) error {
if reason != Install && reason != Upgrade {
panic(fmt.Errorf("%q is not a deploy operation", reason))
}
var hi *hook.Info
if u.s != nil && (u.s.Op == RunHook || u.s.Op == Upgrade) {
// If this upgrade interrupts a RunHook, we need to preserve the hook
// info so that we can return to the appropriate error state. However,
// if we're resuming (or have force-interrupted) an Upgrade, we also
// need to preserve whatever hook info was preserved when we initially
// started upgrading, to ensure we still return to the correct state.
hi = u.s.Hook
}
if u.s == nil || u.s.OpStep != Done {
// Get the new charm bundle before announcing intention to use it.
logger.Infof("fetching charm %q", curl)
sch, err := u.st.Charm(curl)
if err != nil {
return err
}
if err = u.deployer.Stage(sch, u.tomb.Dying()); err != nil {
return err
}
// Set the new charm URL - this returns when the operation is complete,
// at which point we can refresh the local copy of the unit to get a
// version with the correct charm URL, and can go ahead and deploy
// the charm proper.
if err := u.f.SetCharm(curl); err != nil {
return err
}
if err := u.unit.Refresh(); err != nil {
return err
}
logger.Infof("deploying charm %q", curl)
if err = u.writeState(reason, Pending, hi, curl); err != nil {
return err
}
if err = u.deployer.Deploy(); err != nil {
return err
}
if err = u.writeState(reason, Done, hi, curl); err != nil {
return err
}
}
logger.Infof("charm %q is deployed", curl)
status := Queued
if hi != nil {
// If a hook operation was interrupted, restore it.
status = Pending
} else {
// Otherwise, queue the relevant post-deploy hook.
hi = &hook.Info{}
switch reason {
case Install:
hi.Kind = hooks.Install
case Upgrade:
hi.Kind = hooks.UpgradeCharm
}
}
return u.writeState(RunHook, status, hi, nil)
}
func (s *RelationerSuite) TestPrepareCommitHooks(c *gc.C) {
r := uniter.NewRelationer(s.apiRelUnit, s.dir, s.hooks)
err := r.Join()
c.Assert(err, gc.IsNil)
ctx := r.Context()
c.Assert(ctx.UnitNames(), gc.HasLen, 0)
// Check preparing an invalid hook changes nothing.
changed := hook.Info{
Kind: hooks.RelationChanged,
RemoteUnit: "u/1",
ChangeVersion: 7,
}
_, err = r.PrepareHook(changed)
c.Assert(err, gc.ErrorMatches, `inappropriate "relation-changed" for "u/1": unit has not joined`)
c.Assert(ctx.UnitNames(), gc.HasLen, 0)
c.Assert(s.dir.State().Members, gc.HasLen, 0)
// Check preparing a valid hook updates the context, but not persistent
// relation state.
joined := hook.Info{
Kind: hooks.RelationJoined,
RemoteUnit: "u/1",
}
name, err := r.PrepareHook(joined)
c.Assert(err, gc.IsNil)
c.Assert(s.dir.State().Members, gc.HasLen, 0)
c.Assert(name, gc.Equals, "ring-relation-joined")
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1"})
// Check that preparing the following hook fails as before...
_, err = r.PrepareHook(changed)
c.Assert(err, gc.ErrorMatches, `inappropriate "relation-changed" for "u/1": unit has not joined`)
c.Assert(s.dir.State().Members, gc.HasLen, 0)
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1"})
// ...but that committing the previous hook updates the persistent
// relation state...
err = r.CommitHook(joined)
c.Assert(err, gc.IsNil)
c.Assert(s.dir.State().Members, gc.DeepEquals, map[string]int64{"u/1": 0})
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1"})
// ...and allows us to prepare the next hook...
name, err = r.PrepareHook(changed)
c.Assert(err, gc.IsNil)
c.Assert(name, gc.Equals, "ring-relation-changed")
c.Assert(s.dir.State().Members, gc.DeepEquals, map[string]int64{"u/1": 0})
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1"})
// ...and commit it.
err = r.CommitHook(changed)
c.Assert(err, gc.IsNil)
c.Assert(s.dir.State().Members, gc.DeepEquals, map[string]int64{"u/1": 7})
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1"})
// To verify implied behaviour above, prepare a new joined hook with
// missing membership information, and check relation context
// membership is updated appropriately...
joined.RemoteUnit = "u/2"
joined.ChangeVersion = 3
name, err = r.PrepareHook(joined)
c.Assert(err, gc.IsNil)
c.Assert(s.dir.State().Members, gc.HasLen, 1)
c.Assert(name, gc.Equals, "ring-relation-joined")
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1", "u/2"})
// ...and so is relation state on commit.
err = r.CommitHook(joined)
c.Assert(err, gc.IsNil)
c.Assert(s.dir.State().Members, gc.DeepEquals, map[string]int64{"u/1": 7, "u/2": 3})
c.Assert(ctx.UnitNames(), gc.DeepEquals, []string{"u/1", "u/2"})
}