In pursuit of pulumi/pulumi#2389, this commit adds the necessary changes
to the resource monitor protocol so that language hosts can communicate
exactly what version of a provider should be used when servicing an
Invoke, ReadResource, or RegisterResource. The expectation here is that,
if a language host provides a version, the engine MUST use EXACTLY that
version of a provider plugin in order to service the request.
These changes add a new flag to the various `ResourceOptions` types that
indicates that a resource should be deleted before it is replaced, even
if the provider does not require this behavior. The usual
delete-before-replace cascade semantics apply.
Fixes#1620.
This implements the new algorithm for deciding which resources must be
deleted due to a delete-before-replace operation.
We need to compute the set of resources that may be replaced by a
change to the resource under consideration. We do this by taking the
complete set of transitive dependents on the resource under
consideration and removing any resources that would not be replaced by
changes to their dependencies. We determine whether or not a resource
may be replaced by substituting unknowns for input properties that may
change due to deletion of the resources their value depends on and
calling the resource provider's Diff method.
This is perhaps clearer when described by example. Consider the
following dependency graph:
A
__|__
B C
| _|_
D E F
In this graph, all of B, C, D, E, and F transitively depend on A. It may
be the case, however, that changes to the specific properties of any of
those resources R that would occur if a resource on the path to A were
deleted and recreated may not cause R to be replaced. For example, the
edge from B to A may be a simple dependsOn edge such that a change to
B does not actually influence any of B's input properties. In that case,
neither B nor D would need to be deleted before A could be deleted.
In order to make the above algorithm a reality, the resource monitor
interface has been updated to include a map that associates an input
property key with the list of resources that input property depends on.
Older clients of the resource monitor will leave this map empty, in
which case all input properties will be treated as depending on all
dependencies of the resource. This is probably overly conservative, but
it is less conservative than what we currently implement, and is
certainly correct.
* Fix, formalize and add tests for property rewrites
The Python SDK provides two hooks for resources to override how their
properties are communicated to and from the engine. The code that
performs this transformation is subtle and, before this commit, subtly
incorrect.
This commit adds a test that verifies that the SDK correctly transforms
properties recursively according to the two transformation hooks, while
also fixing a smattering of test issues encountered when adding the new
test.
* CR feedback
### First-Class Providers
These changes implement support for first-class providers. First-class
providers are provider plugins that are exposed as resources via the
Pulumi programming model so that they may be explicitly and multiply
instantiated. Each instance of a provider resource may be configured
differently, and configuration parameters may be source from the
outputs of other resources.
### Provider Plugin Changes
In order to accommodate the need to verify and diff provider
configuration and configure providers without complete configuration
information, these changes adjust the high-level provider plugin
interface. Two new methods for validating a provider's configuration
and diffing changes to the same have been added (`CheckConfig` and
`DiffConfig`, respectively), and the type of the configuration bag
accepted by `Configure` has been changed to a `PropertyMap`.
These changes have not yet been reflected in the provider plugin gRPC
interface. We will do this in a set of follow-up changes. Until then,
these methods are implemented by adapters:
- `CheckConfig` validates that all configuration parameters are string
or unknown properties. This is necessary because existing plugins
only accept string-typed configuration values.
- `DiffConfig` either returns "never replace" if all configuration
values are known or "must replace" if any configuration value is
unknown. The justification for this behavior is given
[here](https://github.com/pulumi/pulumi/pull/1695/files#diff-a6cd5c7f337665f5bb22e92ca5f07537R106)
- `Configure` converts the config bag to a legacy config map and
configures the provider plugin if all config values are known. If any
config value is unknown, the underlying plugin is not configured and
the provider may only perform `Check`, `Read`, and `Invoke`, all of
which return empty results. We justify this behavior becuase it is
only possible during a preview and provides the best experience we
can manage with the existing gRPC interface.
### Resource Model Changes
Providers are now exposed as resources that participate in a stack's
dependency graph. Like other resources, they are explicitly created,
may have multiple instances, and may have dependencies on other
resources. Providers are referred to using provider references, which
are a combination of the provider's URN and its ID. This design
addresses the need during a preview to refer to providers that have not
yet been physically created and therefore have no ID.
All custom resources that are not themselves providers must specify a
single provider via a provider reference. The named provider will be
used to manage that resource's CRUD operations. If a resource's
provider reference changes, the resource must be replaced. Though its
URN is not present in the resource's dependency list, the provider
should be treated as a dependency of the resource when topologically
sorting the dependency graph.
Finally, `Invoke` operations must now specify a provider to use for the
invocation via a provider reference.
### Engine Changes
First-class providers support requires a few changes to the engine:
- The engine must have some way to map from provider references to
provider plugins. It must be possible to add providers from a stack's
checkpoint to this map and to register new/updated providers during
the execution of a plan in response to CRUD operations on provider
resources.
- In order to support updating existing stacks using existing Pulumi
programs that may not explicitly instantiate providers, the engine
must be able to manage the "default" providers for each package
referenced by a checkpoint or Pulumi program. The configuration for
a "default" provider is taken from the stack's configuration data.
The former need is addressed by adding a provider registry type that is
responsible for managing all of the plugins required by a plan. In
addition to loading plugins froma checkpoint and providing the ability
to map from a provider reference to a provider plugin, this type serves
as the provider plugin for providers themselves (i.e. it is the
"provider provider").
The latter need is solved via two relatively self-contained changes to
plan setup and the eval source.
During plan setup, the old checkpoint is scanned for custom resources
that do not have a provider reference in order to compute the set of
packages that require a default provider. Once this set has been
computed, the required default provider definitions are conjured and
prepended to the checkpoint's resource list. Each resource that
requires a default provider is then updated to refer to the default
provider for its package.
While an eval source is running, each custom resource registration,
resource read, and invoke that does not name a provider is trapped
before being returned by the source iterator. If no default provider
for the appropriate package has been registered, the eval source
synthesizes an appropriate registration, waits for it to complete, and
records the registered provider's reference. This reference is injected
into the original request, which is then processed as usual. If a
default provider was already registered, the recorded reference is
used and no new registration occurs.
### SDK Changes
These changes only expose first-class providers from the Node.JS SDK.
- A new abstract class, `ProviderResource`, can be subclassed and used
to instantiate first-class providers.
- A new field in `ResourceOptions`, `provider`, can be used to supply
a particular provider instance to manage a `CustomResource`'s CRUD
operations.
- A new type, `InvokeOptions`, can be used to specify options that
control the behavior of a call to `pulumi.runtime.invoke`. This type
includes a `provider` field that is analogous to
`ResourceOptions.provider`.
* Protobuf changes to record dependencies for read resources
* Add a number of tests for read resources, especially around replacement
* Place read resources in the snapshot with "external" bit set
Fixespulumi/pulumi#1521. This commit introduces two new step ops: Read
and ReadReplacement. The engine generates Read and ReadReplacement steps
when servicing ReadResource RPC calls from the language host.
* Fix an omission of OpReadReplace from the step list
* Rebase against master
* Transition to use V2 Resources by default
* Add a semantic "relinquish" operation to the engine
If the engine observes that a resource is read and also that the
resource exists in the snapshot as a non-external resource, it will not
delete the resource if the IDs of the old and new resources match.
* Typo fix
* CR: add missing comments, DeserializeDeployment -> DeserializeDeploymentV2, ID check
This change wires up the new Read RPC method in such a manner that
Pulumi programs can invoke it. This is technically not required for
refreshing state programmatically (as in pulumi/pulumi#1081), however
it's a feature we had eons ago and have wanted since (see
pulumi/pulumi#83), and will allow us to write code like
let vm = aws.ec2.Instance.get("my-vm", "i-07043cd97bd2c9cfc");
// use any property from here on out ...
The way this works is simply by bridging the Pulumi program via its
existing RPC connection to the engine, much like Invoke and
RegisterResource RPC requests already do, and then invoking the proper
resource provider in order to read the state. Note that some resources
cannot be uniquely identified by their ID alone, and so an extra
resource state bag may be provided with just those properties required.
This came almost for free (okay, not exactly) and will come in handy as
we start gaining experience with reading live state from resources.
This commit does two things:
1. All dependencies of a resource, both implicit and explicit, are
communicated directly to the engine when registering a resource. The
engine keeps track of these dependencies and ultimately serializes
them out to the checkpoint file upon successful deployment.
2. Once a successful deployment is done, the new `pulumi stack
graph` command reads the checkpoint file and outputs the dependency
information within in the DOT format.
Keeping track of dependency information within the checkpoint file is
desirable for a number of reasons, most notably delete-before-create,
where we want to delete resources before we have created their
replacement when performing an update.
This change implements resource protection, as per pulumi/pulumi#689.
The overall idea is that a resource can be marked as "protect: true",
which will prevent deletion of that resource for any reason whatsoever
(straight deletion, replacement, etc). This is expressed in the
program. To "unprotect" a resource, one must perform an update setting
"protect: false", and then afterwards, they can delete the resource.
For example:
let res = new MyResource("precious", { .. }, { protect: true });
Afterwards, the resource will display in the CLI with a lock icon, and
any attempts to remove it will fail in the usual ways (in planning or,
worst case, during an actual update).
This was done by adding a new ResourceOptions bag parameter to the
base Resource types. This is unfortunately a breaking change, but now
is the right time to take this one. We had been adding new settings
one by one -- like parent and dependsOn -- and this new approach will
set us up to add any number of additional settings down the road,
without needing to worry about breaking anything ever again.
This is related to protected stacks, as described in
pulumi/pulumi-service#399. Most likely this will serve as a foundational
building block that enables the coarser grained policy management.
This change simplifies the necessary RPC changes for components.
Instead of a Begin/End pair, which complicates the whole system
because now we have the opportunity of a missing End call, we will
simply let RPCs come in that append outputs to existing states.
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.
This change adds back component output properties. Doing so
requires splitting the RPC interface for creating resources in
half, with an initial RegisterResource which contains all of the
input properties, and a final CompleteResource which optionally
contains any output properties synthesized by the component.
This change switches from child lists to parent pointers, in the
way resource ancestries are represented. This cleans up a fair bit
of the old parenting logic, including all notion of ambient parent
scopes (and will notably address pulumi/pulumi#435).
This lets us show a more parent/child display in the output when
doing planning and updating. For instance, here is an update of
a lambda's text, which is logically part of a cloud timer:
* cloud:timer:Timer: (same)
[urn=urn:pulumi:malta::lm-cloud:☁️timer:Timer::lm-cts-malta-job-CleanSnapshots]
* cloud:function:Function: (same)
[urn=urn:pulumi:malta::lm-cloud:☁️function:Function::lm-cts-malta-job-CleanSnapshots]
* aws:serverless:Function: (same)
[urn=urn:pulumi:malta::lm-cloud::aws:serverless:Function::lm-cts-malta-job-CleanSnapshots]
~ aws:lambda/function:Function: (modify)
[id=lm-cts-malta-job-CleanSnapshots-fee4f3bf41280741]
[urn=urn:pulumi:malta::lm-cloud::aws:lambda/function:Function::lm-cts-malta-job-CleanSnapshots]
- code : archive(assets:2092f44) {
// etc etc etc
Note that we still get walls of text, but this will be actually
quite nice when combined with pulumi/pulumi#454.
I've also suppressed printing properties that didn't change during
updates when --detailed was not passed, and also suppressed empty
strings and zero-length arrays (since TF uses these as defaults in
many places and it just makes creation and deletion quite verbose).
Note that this is a far cry from everything we can possibly do
here as part of pulumi/pulumi#340 (and even pulumi/pulumi#417).
But it's a good start towards taming some of our output spew.
