* Test the Python language host end-to-end
This commit introduces an end-to-end language host testing framework for
the Python SDK, similar to what already exists for the Node SDK. The
real language host is used to run Pulumi programs written in Python
while mocking out the resource monitor.
* Add new tests
* Print out better diagnostics when the langhost fails to launch
* Use the in-tree executor for testing
* CR: Place tests and code being tested in the same directory for ease of understanding, add a README
* Turns out I misunderstood the semantics of resource registration - fix two tests so that they pass now and fix a few bugs in the test harness
* Fix a few issues with the Python language host
1. Fix an issue where the UNKNOWN sentinel was leaking into user
programs
2. Fix an issue where Protobuf types were leaking into user programs
In fixing this issues I also added a framework for writing tests against
the Python SDK.
* License headers, and adopt a more idiomatic testing pattern
* Additional idiomatic Python
* That's what I get for trying to be fancy (Travis CI python version is very old and does not respect this form)
* CR feedback: use more comprehensions, typo fix
* Break a circular dependency between resource, runtime.resource, and runtime.rpc
* Don't check in .vscode
* CR: sort inputs, rename global variable, add a test for CustomResource serialization
* Remove accidental code duplication
* Graceful RPC shutdown: CLI side
* Handle unavailable resource monitor in language hosts
* Fix a comment
* Don't commit package-lock.json
* fix mangled pylint pragma
* Rebase against master and fix Gopkg.lock
* Code review feedback
* Fix a race between closing the callerEventsOpt channel and terminating a goroutine that writes to it
* glog -> logging
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 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 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
Implement Python invoke RPC
This change implements the invoke function for resource provider
RPCs. This is required to support a customer scenario.
There are a few other minor updates:
* Rename pulumi.export to pulumi.output.
* Change register_resource to, like invoke, return the resulting
object/dictionary, instead of the set_outputs function.
* Initialize the monitor/engine RPC connections to None when not
attached to the engine, thus ensuring good error messages.
* Fix Python project/stack metadata
This change uses virtualenv to insulate us from platform differences
in our building of the Python SDK, and to create an isolated Python 2
environment. This includes meaning we don't need to worry about the
specific location and behavior of Pylint. I *think* this will work
no matter whether it's Mac, Ubuntu, ArchLinux, Windows, and so on.
We do install to the --user directory in the install target using
`pip install -e`, however, which enables the machine-wide symlinking
that we need to support various workflows.
This fixespulumi/pulumi#1007.
This change includes a lot more functionality. Enough to actually
run the webserver-py example through previews, updates, and destroys!
* Actually wire up the gRPC connections to the engine/monitor.
* Move the Node.js and Python generated Protobuf/gRPC files underneath
the actual SDK directories to simplify this generally. No more
copying during `make` and, in fact, this was required to give a smoother
experience with good packages/modules for the Python's SDK development.
* Build the Python egg during `make build`.
* Add support for program stacks. Just like with the Node.js runtime,
we will auto-parent any resources without explicit parents to a single
top-level resource component.
* Add support for component resource output properties.
* Add get_project() and get_stack() functions for retrieving the current
project and stack names.
* Properly use UNKNOWN sentinels.
* Add a set_outputs() function on Resource. This is defined by the
code-generator and allows custom logic for output property setting.
This is cleaner than the way we do this in Node.js, and gives us a
way to ensure that output properties are "real" properties, complete
with member documentation. This also gives us a hook to perform
name demangling, which the code-generator typically controls anyway.
* Add package dependencies to setuptools.py and requirements.txt.
This change gets enough of the Python SDK up and running that the
empty Python program will work. Mostly just scaffolding, but the
basic structure is now in place. The primary remaining work is to
wire up resource creation to the gRPC interfaces.
In summary:
* The basic structure is as follows:
- Everything goes into sdk/python/.
- sdk/python/cmd/pulumi-langhost-python is a Go language host
that simply knows how to spawn Python processes to run out
entrypoint in response to requests by the engine.
- sdk/python/cmd/pulumi-langhost-python-exec is a little Python
shim that is invoked by the language host to run Python programs,
and is responsible for setting up the minimal goo before we can
do so (RPC connections and the like).
- sdk/python/lib/ contains a Python Pip package suitable for PyPi.
- In there, we have two packages: the root pulumi package that
contains all of the basic Pulumi programming model abstractions,
and pulumi.runtime, which contains the implementation of
resource registration, RPC interfacing with the engine, and so on.
* Add logic in our test framework to conditionalize on the language
type and react accordingly. This will allow us to skip Yarn for
Python projects and eventually run Pip if there's a requirements.txt.
* Created the basic project structure, including all of the usual
Make targets for installing into the proper places.
* Building also runs Pylint and we are clean.
There are a few other minor things in here:
* Add an "empty" test for both Node.js and Python. These pass.
* Fix an existing bug in plugin shutdown logic. At some point, we
started waiting for stderr/stdout to flush before shutting down
the plugin; but if certain failures happen "early" during the
plugin launch process, these channels will never get initialized
and so waiting for them deadlocks.
* Recently we seem to have added logic to delete test temp
directories if a failure happened during initialization of said
temp directories. This is unfortunate, because you often need to
look at the temp directory to see what failed. We already clean
them up elsewhere after the full test completes successfully, so
I don't think we need to be doing this, and I've removed it.
Still many loose ends (config, resources, etc), but it's a start!
