Adds initial support for resource methods (via a new `Call` gRPC method similar to `Invoke`), with support for authoring methods from Node.js, and calling methods from Python.
Resources are serialized as their URN, ID, and package version. Each
Pulumi package is expected to register itself with the SDK. The package
will be invoked to construct appropriate instances of rehydrated
resources. Packages are distinguished by their name and their version.
This is the foundation of cross-process resources.
Related to #2430.
Co-authored-by: Mikhail Shilkov <github@mikhail.io>
Co-authored-by: Luke Hoban <luke@pulumi.com>
Co-authored-by: Levi Blackstone <levi@pulumi.com>
These changes add support for provider-side previews of create and
update operations, which allows resource providers to supply output
property values for resources that are being created or updated during a
preview.
If a plugin supports provider-side preview, its create/update methods
will be invoked during previews with the `preview` property set to true.
It is the responsibility of the provider to fill in any output
properties that are known before returning. It is a best practice for
providers to only fill in property values that are guaranteed to be
identical if the preview were instead an update (i.e. only those output
properties whose values can be conclusively determined without
actually performing the create/update operation should be populated).
Providers that support previews must accept unknown values in their
create and update methods.
If a plugin does not support provider-side preview, the inputs to a
create or update operation will be propagated to the outputs as they are
today.
Fixes#4992.
These changes add initial support for the construction of remote
components. For now, this support is limited to the NodeJS SDK;
follow-up changes will implement support for the other SDKs.
Remote components are component resources that are constructed and
managed by plugins rather than by Pulumi programs. In this sense, they
are a bit like cloud resources, and are supported by the same
distribution and plugin loading mechanisms and described by the same
schema system.
The construction of a remote component is initiated by a
`RegisterResourceRequest` with the new `remote` field set to `true`.
When the resource monitor receives such a request, it loads the plugin
that implements the component resource and calls the `Construct`
method added to the resource provider interface as part of these
changes. This method accepts the information necessary to construct the
component and its children: the component's name, type, resource
options, inputs, and input dependencies. It is responsible for
dispatching to the appropriate component factory to create the
component, then returning its URN, resolved output properties, and
output property dependencies. The dependency information is necessary to
support features such as delete-before-replace, which rely on precise
dependency information for custom resources.
These changes also add initial support for more conveniently
implementing resource providers in NodeJS. The interface used to
implement such a provider is similar to the dynamic provider interface
(and may be unified with that interface in the future).
An example of a NodeJS program constructing a remote component resource
also implemented in NodeJS can be found in
`tests/construct_component/nodejs`.
This is the core of #2430.
These changes add a new method to the resource provider gRPC interface,
`GetSchema`, that allows consumers of these providers to extract
JSON-serialized schema information for the provider's types, resources,
and functions.
These changes restore a more-correct version of the behavior that was
disabled with #3014. The original implementation of this behavior was
done in the SDKs, which do not have access to the complete inputs for a
resource (in particular, default values filled in by the provider during
`Check` are not exposed to the SDK). This lack of information meant that
the resolved output values could disagree with the typings present in
a provider SDK. Exacerbating this problem was the fact that unknown
values were dropped entirely, causing `undefined` values to appear in
unexpected places.
By doing this in the engine and allowing unknown values to be
represented in a first-class manner in the SDK, we can attack both of
these issues.
Although this behavior is not _strictly_ consistent with respect to the
resource model--in an update, a resource's output properties will come
from its provider and may differ from its input properties--this
behavior was present in the product for a fairly long time without
significant issues. In the future, we may be able to improve the
accuracy of resource outputs during a preview by allowing the provider
to dry-run CRUD operations and return partially-known values where
possible.
These changes also introduce new APIs in the Node and Python SDKs
that work with unknown values in a first-class fashion:
- A new parameter to the `apply` function that indicates that the
callback should be run even if the result of the apply contains
unknown values
- `containsUnknowns` and `isUnknown`, which return true if a value
either contains nested unknown values or is exactly an unknown value
- The `Unknown` type, which represents unknown values
The primary use case for these APIs is to allow nested, properties with
known values to be accessed via the lifted property accessor even when
the containing property is not fully know. A common example of this
pattern is the `metadata.name` property of a Kubernetes `Namespace`
object: while other properties of the `metadata` bag may be unknown,
`name` is often known. These APIs allow `ns.metadata.name` to return a
known value in this case.
In order to avoid exposing downlevel SDKs to unknown values--a change
which could break user code by exposing it to unexpected values--a
language SDK must indicate whether or not it supports first-class
unknown values as part of each `RegisterResourceRequest`.
These changes also allow us to avoid breaking user code with the new
behavior introduced by the prior commit.
Fixes#3190.
These changes add support for passing `ignoreChanges` paths to resource
providers. This is intended to accommodate providers that perform diffs
between resource inputs and resource state (e.g. all Terraform-based
providers, the k8s provider when using API server dry-runs). These paths
are specified using the same syntax as the paths used in detailed diffs.
In addition to passing these paths to providers, the existing support
for `ignoreChanges` in inputs has been extended to accept paths rather
than top-level keys. It is an error to specify a path that is missing
one or more component in the old or new inputs.
Fixes#2936, #2663.
* Plumbing the custom timeouts from the engine to the providers
* Plumbing the CustomTimeouts through to the engine and adding test to show this
* Change the provider proto to include individual timeouts
* Plumbing the CustomTimeouts from the engine through to the Provider RPC interface
* Change how the CustomTimeouts are sent across RPC
These errors were spotted in testing. We can now see that the timeout
information is arriving in the RegisterResourceRequest
```
req=&pulumirpc.RegisterResourceRequest{
Type: "aws:s3/bucket:Bucket",
Name: "my-bucket",
Parent: "urn:pulumi:dev::aws-vpc::pulumi:pulumi:Stack::aws-vpc-dev",
Custom: true,
Object: &structpb.Struct{},
Protect: false,
Dependencies: nil,
Provider: "",
PropertyDependencies: {},
DeleteBeforeReplace: false,
Version: "",
IgnoreChanges: nil,
AcceptSecrets: true,
AdditionalSecretOutputs: nil,
Aliases: nil,
CustomTimeouts: &pulumirpc.RegisterResourceRequest_CustomTimeouts{
Create: 300,
Update: 400,
Delete: 500,
XXX_NoUnkeyedLiteral: struct {}{},
XXX_unrecognized: nil,
XXX_sizecache: 0,
},
XXX_NoUnkeyedLiteral: struct {}{},
XXX_unrecognized: nil,
XXX_sizecache: 0,
}
```
* Changing the design to use strings
* CHANGELOG entry to include the CustomTimeouts work
* Changing custom timeouts to be passed around the engine as converted value
We don't want to pass around strings - the user can provide it but we want
to make the engine aware of the timeout in seconds as a float64
Thse changes make a subtle but critical adjustment to the process the
Pulumi engine uses to determine whether or not a difference exists
between a resource's actual and desired states, and adjusts the way this
difference is calculated and displayed accordingly.
Today, the Pulumi engine get the first chance to decide whether or not
there is a difference between a resource's actual and desired states. It
does this by comparing the current set of inputs for a resource (i.e.
the inputs from the running Pulumi program) with the last set of inputs
used to update the resource. If there is no difference between the old
and new inputs, the engine decides that no change is necessary without
consulting the resource's provider. Only if there are changes does the
engine consult the resource's provider for more information about the
difference. This can be problematic for a number of reasons:
- Not all providers do input-input comparison; some do input-state
comparison
- Not all providers are able to update the last deployed set of inputs
when performing a refresh
- Some providers--either intentionally or due to bugs--may see changes
in resources whose inputs have not changed
All of these situations are confusing at the very least, and the first
is problematic with respect to correctness. Furthermore, the display
code only renders diffs it observes rather than rendering the diffs
observed by the provider, which can obscure the actual changes detected
at runtime.
These changes address both of these issues:
- Rather than comparing the current inputs against the last inputs
before calling a resource provider's Diff function, the engine calls
the Diff function in all cases.
- Providers may now return a list of properties that differ between the
requested and actual state and the way in which they differ. This
information will then be used by the CLI to render the diff
appropriately. A provider may also indicate that a particular diff is
between old and new inputs rather than old state and new inputs.
Fixes#2453.
Adds a new resource option `aliases` which can be used to rename a resource. When making a breaking change to the name or type of a resource or component, the old name can be added to the list of `aliases` for a resource to ensure that existing resources will be migrated to the new name instead of being deleted and replaced with the new named resource.
There are two key places this change is implemented.
The first is the step generator in the engine. When computing whether there is an old version of a registered resource, we now take into account the aliases specified on the registered resource. That is, we first look up the resource by its new URN in the old state, and then by any aliases provided (in order). This can allow the resource to be matched as a (potential) update to an existing resource with a different URN.
The second is the core `Resource` constructor in the JavaScript (and soon Python) SDKs. This change ensures that when a parent resource is aliased, that all children implicitly inherit corresponding aliases. It is similar to how many other resource options are "inherited" implicitly from the parent.
Four specific scenarios are explicitly tested as part of this PR:
1. Renaming a resource
2. Adopting a resource into a component (as the owner of both component and consumption codebases)
3. Renaming a component instance (as the owner of the consumption codebase without changes to the component)
4. Changing the type of a component (as the owner of the component codebase without changes to the consumption codebase)
4. Combining (1) and (3) to make both changes to a resource at the same time
In our system, we model secrets as outputs with an additional bit of
metadata that says they are secret. For Read and Register resource
calls, our RPC interface says if the client side of the interface can
handle secrets being returned (i.e. the language SDK knows how to
sniff for the special signiture and resolve the output with the
special bit set).
For Invoke, we have no such model. Instead, we return a `Promise<T>`
where T's shape has just regular property fields. There's no place
for us to tack the secretness onto, since there are no Outputs.
So, for now, don't even return secret values back across the invoke
channel. We can still take them as arguments (which is good) but we
can't even return secrets as part of invoke calls. This is not ideal,
but given the way we model these sources, there's no way around
this. Fortunately, the result of these invoke calls are not stored in
the checkpoint and since the type is not Output<T> it will be clear
that the underlying value is just present in plaintext. A user that
wants to pass the result of an invoke into a resource can turn an
existing property into a secret via `pulumi.secret`.
`pulumi query` requires that language plugins know about "query mode" so
that they don't do things like try to register the default stack
resource.
To communicate that a language host should boot into query mode, we
augment the language plugin protocol to include this information.
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 take advantage of the newly-added support for returning
inputs from Read to update a resource's inputs as part of a refresh.
As a consequence, the Pulumi engine will now properly detect drift
between the actual state of a resource and the desired state described
by the program and generate appropriate update or replace steps.
As part of these changes, a resource's old inputs are now passed to the
provider when performing a refresh. The provider can take advantage of
this to maintain the accuracy of any additional data or metadata in the
resource's inputs that may need to be updated during the refresh.
This is required for the complete implementation of
https://github.com/pulumi/pulumi-terraform/pull/349. Without access to
the old inputs for a resource, TF-based providers would lose all
information about default population during a refresh.
These changes add two new methods to the provider interface and extend
the results of three others.
The new methods are `CheckConfig` and `DiffConfig`, which fill out the
set of methods required for a complete implementation of the
first-class provider design. Though these methods are optional for
backwards compatibility, they should be implemented by all future
providers for the best possible user experience.
The adjusted result types are `DiffResponse`, `ReadResponse`, and
`ErrorResourceInitFailed`. The first has been updated to include a list
of the properties that changed (if any). The latter two now include
an estimated set of inputs for the resource as well as the resource's
state. Together, these three changes enable the engine to determine the
set of inputs that should be specified by a user in order to match those
that describe the resource's current state.
This contributes to #2453, #1662, #1635, and #1718.
### 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`.
A critical part of the partial update protocol is to return a structured
error when a resource is successfully created, but fails to initialize.
This structured error contains the properties of the
partially-initialized resource, and instructs the engine to halt.
Most languages implement this by attaching "details" to the error, i.e.,
an arbitrary proto message attached to the error. The JavaScript
implementation is not mature enough to include all the facilities
required to use this, so here we must add a `Status` message, which
protobuf requires as part of its structure for returning details.
The RPC provider interface needs a way to convey back to the engine
that a resource being read no longer exists. To do this, we'll return
the ID property that was read back. If it is empty, it means the
resource is gone. If it is non-empty, we expect it to match the input.
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.
* Improve the error message arising from missing required configs for
resource providers
If the resource provider that we are speaking to is new enough, it will send
across a list of keys and their descriptions alongside an error
indicating that the provider we are configuring is missing required
config. This commit packages up the list of missing keys into an error
that can be presented nicely to the user.
* Code review feedback: renaming simplification and correcting errors in comments
* Send structured errors across RPC boundaries
This brings us closer to gRPC best practices where we send structured
errors with error codes across RPC endpoints. The new "rpcerrors"
package can wrap errors from RPC endpoints, so RPC servers can attach
some additional context as to why a request failed.
* Code review feedback:
1. Rename rpcerrors -> rpcerror, better package name
2. Rename RPCError -> Error, RPCErrorCause -> ErrorCause, names
suggested by gometalinter to improve their package-qualified names
3. Fix import organization in rpcerror.go
This change includes a bunch of refactorings I made in prep for
doing refresh (first, the command, see pulumi/pulumi#1081):
* The primary change is to change the way the engine's core update
functionality works with respect to deploy.Source. This is the
way we can plug in new sources of resource information during
planning (and, soon, diffing). The way I intend to model refresh
is by having a new kind of source, deploy.RefreshSource, which
will let us do virtually everything about an update/diff the same
way with refreshes, which avoid otherwise duplicative effort.
This includes changing the planOptions (nee deployOptions) to
take a new SourceFunc callback, which is responsible for creating
a source specific to the kind of plan being requested.
Preview, Update, and Destroy now are primarily differentiated by
the kind of deploy.Source that they return, rather than sprinkling
things like `if Destroying` throughout. This tidies up some logic
and, more importantly, gives us precisely the refresh hook we need.
* Originally, we used the deploy.NullSource for Destroy operations.
This simply returns nothing, which is how Destroy works. For some
reason, we were no longer doing this, and instead had some
`if Destroying` cases sprinkled throughout the deploy.EvalSource.
I think this is a vestige of some old way we did configuration, at
least judging by a comment, which is apparently no longer relevant.
* Move diff and diff-printing logic within the engine into its own
pkg/engine/diff.go file, to prepare for upcoming work.
* I keep noticing benign diffs anytime I regenerate protobufs. I
suspect this is because we're also on different versions. I changed
generate.sh to also dump the version into grpc_version.txt. At
least we can understand where the diffs are coming from, decide
whether to take them (i.e., a newer version), and ensure that as
a team we are monotonically increasing, and not going backwards.
* I also tidied up some tiny things I noticed while in there, like
comments, incorrect types, lint suppressions, and so on.
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 adds rudimentary delete-before-create support (see
pulumi/pulumi#450). This cannot possibly be complete until we also
implement pulumi/pulumi#624, becuase we may try to delete a resource
while it still has dependent resources (which almost certainly will
fail). But until then, we can use this to manually unwedge ourselves
for leaf-node resources that do not support old and new resources
living side-by-side.
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.
This change adds the capability for a resource provider to indicate
that, where an action carried out in response to a diff, a certain set
of properties would be "stable"; that is to say, they are guaranteed
not to change. As a result, properties may be resolved to their final
values during previewing, avoiding erroneous cascading impacts.
This avoids the ever-annoying situation I keep running into when demoing:
when adding or removing an ingress rule to a security group, we ripple
the impact through the instance, and claim it must be replaced, because
that instance depends on the security group via its name. Well, the name
is a great example of a stable property, in that it will never change, and
so this is truly unfortunate and always adds uncertainty into the demos.
Particularly since the actual update doesn't need to perform replacements.
This resolvespulumi/pulumi#330.
This change enables us to make progress on exposing data sources
(see pulumi/pulumi-terraform#29). The idea is to have an Invoke
function that simply takes a function token and arguments, performs
the function lookup and invocation, and then returns a return value.
This includes a few changes:
* The repo name -- and hence the Go modules -- changes from pulumi-fabric to pulumi.
* The Node.js SDK package changes from @pulumi/pulumi-fabric to just pulumi.
* The CLI is renamed from lumi to pulumi.
As explained in pulumi/pulumi-fabric#293, we were a little ad-hoc in
how configuration was "applied" to resource providers.
In fact, config wasn't ever communicated directly to providers; instead,
the resource providers would simply ask the engine to read random heap
locations (via tokens). Now that we're on a plan where configuration gets
handed to the program at startup, and that's that, and where generally
speaking resource providers never communicate directly with the language
runtime, we need to take a different approach.
As such, the resource provider interface now offers a Configure RPC
method that the resource planning engine will invoke at the right
times with the right subset of configuration variables filtered to
just that provider's package. This fixespulumi/pulumi#293.
This change simplifies the provider RPC interface slightly:
1) Eliminate Get. We really don't need it anymore. There are
several possibly-interesting scenarios down the road that may
demand it, but when we get there, we can consider how best to
bring this back. Furthermore, the old-style Get remains mostly
incompatible with Terraform anyway.
2) Pass URNs, not type tokens, across the RPC boundary. This gives
the provider access to more interesting information: the type,
still, but also the name (which is no longer an object property).
This is the initial step towards redefining Lumi as a library that runs
atop vanilla Node.js/V8, rather than as its own runtime.
This change is woefully incomplete but this includes some of the more
stable pieces of my current work-in-progress.
The new structure is that within the sdk/ directory we will have a client
library per language. This client library contains the object model for
Lumi (resources, properties, assets, config, etc), in addition to the
"language runtime host" components required to interoperate with the
Lumi resource monitor. This resource monitor is effectively what we call
"Lumi" today, in that it's the thing orchestrating plans and deployments.
Inside the sdk/ directory, you will find nodejs/, the Node.js client
library, alongside proto/, the definitions for RPC interop between the
different pieces of the system. This includes existing RPC definitions
for resource providers, etc., in addition to the new ones for hosting
different language runtimes from within Lumi.
These new interfaces are surprisingly simple. There is effectively a
bidirectional RPC channel between the Lumi resource monitor, represented
by the lumirpc.ResourceMonitor interface, and each language runtime,
represented by the lumirpc.LanguageRuntime interface.
The overall orchestration goes as follows:
1) Lumi decides it needs to run a program written in language X, so
it dynamically loads the language runtime plugin for language X.
2) Lumi passes that runtime a loopback address to its ResourceMonitor
service, while language X will publish a connection back to its
LanguageRuntime service, which Lumi will talk to.
3) Lumi then invokes LanguageRuntime.Run, passing information like
the desired working directory, program name, arguments, and optional
configuration variables to make available to the program.
4) The language X runtime receives this, unpacks it and sets up the
necessary context, and then invokes the program. The program then
calls into Lumi object model abstractions that internally communicate
back to Lumi using the ResourceMonitor interface.
5) The key here is ResourceMonitor.NewResource, which Lumi uses to
serialize state about newly allocated resources. Lumi receives these
and registers them as part of the plan, doing the usual diffing, etc.,
to decide how to proceed. This interface is perhaps one of the
most subtle parts of the new design, as it necessitates the use of
promises internally to allow parallel evaluation of the resource plan,
letting dataflow determine the available concurrency.
6) The program exits, and Lumi continues on its merry way. If the program
fails, the RunResponse will include information about the failure.
Due to (5), all properties on resources are now instances of a new
Property<T> type. A Property<T> is just a thin wrapper over a T, but it
encodes the special properties of Lumi resource properties. Namely, it
is possible to create one out of a T, other Property<T>, Promise<T>, or
to freshly allocate one. In all cases, the Property<T> does not "settle"
until its final state is known. This cannot occur before the deployment
actually completes, and so in general it's not safe to depend on concrete
resolutions of values (unlike ordinary Promise<T>s which are usually
expected to resolve). As a result, all derived computations are meant to
use the `then` function (as in `someValue.then(v => v+x)`).
Although this change includes tests that may be run in isolation to test
the various RPC interactions, we are nowhere near finished. The remaining
work primarily boils down to three things:
1) Wiring all of this up to the Lumi code.
2) Fixing the handful of known loose ends required to make this work,
primarily around the serialization of properties (waiting on
unresolved ones, serializing assets properly, etc).
3) Implementing lambda closure serialization as a native extension.
This ongoing work is part of pulumi/pulumi-fabric#311.
2017-09-04 11:35:20 -07:00
Renamed from sdk/go/pkg/lumirpc/provider.pb.go (Browse further)
