pulumi/pkg/resource/deploy/source_fixed.go
joeduffy c5b7b6ef11 Bring back component outputs
This change brings back component outputs to the overall system again.
In doing so, it generally overhauls the way we do resource RPCs a bit:

* Instead of RegisterResource and CompleteResource, we call these
  BeginRegisterResource and EndRegisterResource, which begins to model
  these as effectively "asynchronous" resource requests.  This should also
  help with parallelism (https://github.com/pulumi/pulumi/issues/106).

* Flip the CLI/engine a little on its head.  Rather than it driving the
  planning and deployment process, we move more to a model where it
  simply observes it.  This is done by implementing an event handler
  interface with three events: OnResourceStepPre, OnResourceStepPost,
  and OnResourceComplete.  The first two are invoked immediately before
  and after any step operation, and the latter is invoked whenever a
  EndRegisterResource comes in.  The reason for the asymmetry here is
  that the checkpointing logic in the deployment engine is largely
  untouched (intentionally, as this is a sensitive part of the system),
  and so the "begin"/"end" nature doesn't flow through faithfully.

* Also make the engine more event-oriented in its terminology and the
  way it handles the incoming BeginRegisterResource and
  EndRegisterResource events from the language host.  This is the first
  step down a long road of incrementally refactoring the engine to work
  this way, a necessary prerequisite for parallelism.
2017-11-29 07:42:14 -08:00

55 lines
1.3 KiB
Go

// Copyright 2016-2017, Pulumi Corporation. All rights reserved.
package deploy
import (
"github.com/pulumi/pulumi/pkg/tokens"
)
// NewFixedSource returns a valid planning source that is comprised of a list of pre-computed steps.
func NewFixedSource(ctx tokens.PackageName, steps []SourceEvent) Source {
return &fixedSource{ctx: ctx, steps: steps}
}
// A fixedSource just returns from a fixed set of resource states.
type fixedSource struct {
ctx tokens.PackageName
steps []SourceEvent
}
func (src *fixedSource) Close() error {
return nil // nothing to do.
}
func (src *fixedSource) Pkg() tokens.PackageName {
return src.ctx
}
func (src *fixedSource) Info() interface{} {
return nil
}
func (src *fixedSource) Iterate(opts Options) (SourceIterator, error) {
return &fixedSourceIterator{
src: src,
current: -1,
}, nil
}
// fixedSourceIterator always returns nil, nil in response to Next, indicating that it is done.
type fixedSourceIterator struct {
src *fixedSource
current int
}
func (iter *fixedSourceIterator) Close() error {
return nil // nothing to do.
}
func (iter *fixedSourceIterator) Next() (SourceEvent, error) {
iter.current++
if iter.current >= len(iter.src.steps) {
return nil, nil
}
return iter.src.steps[iter.current], nil
}