This commit adds CLI support for resource providers to provide partial
state upon failure. For resource providers that model resource
operations across multiple API calls, the Provider RPC interface can now
accomodate saving bags of state for resource operations that failed.
This is a common pattern for Terraform-backed providers that try to do
post-creation steps on resource as part of Create or Update resource
operations.
* Delete Before Create
This commit implements the full semantics of delete before create. If a
resource is replaced and requires deletion before creation, the engine
will use the dependency graph saved in the snapshot to delete all
resources that depend on the resource being replaced prior to the
deletion of the resource to be replaced.
* Rebase against master
* CR: Simplify the control flow in makeRegisterResourceSteps
* Run Check on new inputs when re-creating a resource
* Fix an issue where the planner emitted benign but incorrect deletes of DBR-deleted resources
* CR: produce the list of dependent resources in dependency order and iterate over the list in reverse
* CR: deps->dependents, fix an issue with DependingOn where duplicate nodes could be added to the dependent set
* CR: Fix an issue where we were considering old defaults and new inputs
inappropriately when re-creating a deleted resource
* CR: save 'iter.deletes[urn]' as a local, iterate starting at cursorIndex + 1 for dependency graph
This changes two primary things about dynamic providers:
1) Always echo back the __provider upon read, even if there is a
missing read function on the dynamic provider. In fact, return
the full input state in that case.
2) Store the __provider in the output state of the dynamic resource,
in addition to the input state. My recollection of the "model"
discussion we had weeks ago was that the output properties are
mean to capture the state of a resource in its entirety; not having
this meant that refresh would marshal the outputs only, and find
on the other side of the RPC boundary that __provider was missing.
Note that an alternative to the latter fix would be to use some hybrid
of input and output state, as we used to do, by merging property maps.
This commit changes two things about our resource model:
* Stop performing Pulumi Engine-side diffing of resource state.
Instead, we defer to the resource plugins themselves to determine
whether a change was made and, if so, the extent of it. This
manifests as a simple change to the Diff function; it is done in
a backwards compatible way so that we continue with legacy diffing
for existing resource provider plugins.
* Add a Read RPC method for resource providers. It simply takes a
resource's ID and URN, plus an optional bag of further qualifying
state, and it returns the current property state as read back from
the actual live environment. Note that the optional bag of state
must at least include enough additional properties for resources
wherein the ID is insufficient for the provider to perform a lookup.
It may, however, include the full bag of prior state, for instance
in the case of a refresh operation.
This is part of pulumi/pulumi#1108.
As documented in issue #616, the inputs/defaults/outputs model we have
today has fundamental problems. The crux of the issue is that our
current design requires that defaults present in the old state of a
resource are applied to the new inputs for that resource.
Unfortunately, it is not possible for the engine to decide which
defaults remain applicable and which do not; only the provider has that
knowledge.
These changes take a more tactical approach to resolving this issue than
that originally proposed in #616 that avoids breaking compatibility with
existing checkpoints. Rather than treating the Pulumi inputs as the
provider input properties for a resource, these inputs are first
translated by `Check`. In order to accommodate provider defaults that
were chosen for the old resource but should not change for the new,
`Check` now takes the old provider inputs as well as the new Pulumi
inputs. Rather than the Pulumi inputs and provider defaults, the
provider inputs returned by `Check` are recorded in the checkpoint file.
Put simply, these changes remove defaults as a first-class concept
(except inasmuch as is required to retain the ability to read old
checkpoint files) and move the responsibilty for manging and
merging defaults into the provider that supplies them.
Fixes#616.
This change adds a new manifest section to the checkpoint files.
The existing time moves into it, and we add to it the version of
the Pulumi CLI that created it, along with the names, types, and
versions of all plugins used to generate the file. There is a
magic cookie that we also use during verification.
This is to help keep us sane when debugging problems "in the wild,"
and I'm sure we will add more to it over time (checksum, etc).
For example, after an up, you can now see this in `pulumi stack`:
```
Current stack is demo:
Last updated at 2017-12-01 13:48:49.815740523 -0800 PST
Pulumi version v0.8.3-79-g1ab99ad
Plugin pulumi-provider-aws [resource] version v0.8.3-22-g4363e77
Plugin pulumi-langhost-nodejs [language] version v0.8.3-79-g77bb6b6
Checkpoint file is /Users/joeduffy/dev/code/src/github.com/pulumi/pulumi-aws/.pulumi/stacks/webserver/demo.json
```
This addresses pulumi/pulumi#628.
A dynamic resource is a resource whose provider is implemented alongside
the resource itself. This provider may close over and use orther
resources in the implementation of its CRUD operations. The provider
itself must be stateless, as each CRUD operation for a particular
dynamic resource type may use an independent instance of the provider.
Changes to the definition of a resource's provider result in replacement
of the resource itself (rather than a simple update), as this allows the
old provider definition to delete the old resource and the new provider
definition to create an appropriate replacement.
