This change adds a GetRequiredPlugins RPC method to the language
host, enabling us to query it for its list of plugin requirements.
This is language-specific because it requires looking at the set
of dependencies (e.g., package.json files).
It also adds a call up front during any update/preview operation
to compute the set of plugins and require that they are present.
These plugins are populated in the cache and will be used for all
subsequent plugin-related operations during the engine's activity.
We now cache the language plugins, so that we may load them
eagerly too, which we never did previously due to the fact that
we needed to pass the monitor address at load time. This was a
bit bizarre anyhow, since it's really the Run RPC function that
needs this information. So, to enable caching and eager loading
-- which we need in order to invoke GetRequiredPlugins -- the
"phone home" monitor RPC address is passed at Run time.
In a subsequent change, we will switch to faulting in the plugins
that are missing -- rather than erroring -- in addition to
supporting the `pulumi plugin install` CLI command.
This change introduces a workspace.GetPluginPath function that probes
the central workspace cache of plugins for a matching plugin binary that
matches the desired kind, name, and, optionally, version. It also permits
overriding this with $PATH for developer scenarios.
The analyzer, language, and resource plugin logic now uses this function
for deciding which binary path to load at runtime.
This change implements basic plugin management, but we do not yet
actually use the plugins for anything (that comes next).
Plugins are stored in `~/.pulumi/plugins`, and are expected to be
in the format `pulumi-<KIND>-<NAME>-v<VERSION>[.exe]`. The KIND is
one of `analyzer`, `language`, or `resource`, the NAME is a hyphen-
delimited name (e.g., `aws` or `foo-bar`), and VERSION is the
plugin's semantic version (e.g., `0.9.11`, `1.3.7-beta.a736cf`, etc).
This commit includes four new CLI commands:
* `pulumi plugin` is the top-level plugin command. It does nothing
but show the help text for associated child commands.
* `pulumi plugin install` can be used to install plugins manually.
If run with no additional arguments, it will compute the set of
plugins used by the current project, and download them all. It
may be run to explicitly download a single plugin, however, by
invoking it as `pulumi plugin install KIND NAME VERSION`. For
example, `pulumi plugin install resource aws v0.9.11`. By default,
this command uses the cloud backend in the usual way to perform the
download, although a separate URL may be given with --cloud-url,
just like all other commands that interact with our backend service.
* `pulumi plugin ls` lists all plugins currently installed in the
plugin cache. It displays some useful statistics, like the size
of the plugin, when it was installed, when it was last used, and
so on. It sorts the display alphabetically by plugin name, and
for plugins with multiple versions, it shows the newest at the top.
The command also summarizes how much disk space is currently being
consumed by the plugin cache. There are no filtering capabilities yet.
* `pulumi plugin prune` will delete plugins from the cache. By
default, when run with no arguments, it will delete everything.
It may be run with additional arguments, KIND, NAME, and VERSION,
each one getting more specific about what it will delete. For
instance, `pulumi plugin prune resource aws` will delete all AWS
plugin versions, while `pulumi plugin prune resource aws <0.9`
will delete all AWS plugins before version 0.9. Unless --yes is
passed, the command will confirm the deletion with a count of how
many plugins will be affected by the command.
We do not yet actually download plugins on demand yet. That will
come in a subsequent change.
