5 Commits (e2d73e78ad8a01dc486b23f90dc9bd1c8a09ba34)

Author	SHA1	Message	Date
Paddy	5127f1ef8b	command: Unmanaged providers ... This adds supports for "unmanaged" providers, or providers with process lifecycles not controlled by Terraform. These providers are assumed to be started before Terraform is launched, and are assumed to shut themselves down after Terraform has finished running. To do this, we must update the go-plugin dependency to v1.3.0, which added support for the "test mode" plugin serving that powers all this. As a side-effect of not needing to manage the process lifecycle anymore, Terraform also no longer needs to worry about the provider's binary, as it won't be used for anything anymore. Because of this, we can disable the init behavior that concerns itself with downloading that provider's binary, checking its version, and otherwise managing the binary. This is all managed on a per-provider basis, so managed providers that Terraform downloads, starts, and stops can be used in the same commands as unmanaged providers. The TF_REATTACH_PROVIDERS environment variable is added, and is a JSON encoding of the provider's address to the information we need to connect to it. This change enables two benefits: first, delve and other debuggers can now be attached to provider server processes, and Terraform can connect. This allows for attaching debuggers to provider processes, which before was difficult to impossible. Second, it allows the SDK test framework to host the provider in the same process as the test driver, while running a production Terraform binary against the provider. This allows for Go's built-in race detector and test coverage tooling to work as expected in provider tests. Unmanaged providers are expected to work in the exact same way as managed providers, with one caveat: Terraform kills provider processes and restarts them once per graph walk, meaning multiple times during most Terraform CLI commands. As unmanaged providers can't be killed by Terraform, and have no visibility into graph walks, unmanaged providers are likely to have differences in how their global mutable state behaves when compared to managed providers. Namely, unmanaged providers are likely to retain global state when managed providers would have reset it. Developers relying on global state should be aware of this.	6 years ago
Martin Atkins	958ea4f7d1	internal/providercache: Handle built-in providers ... Built-in providers are special providers that are distributed as part of Terraform CLI itself, rather than being installed separately. They always live in the terraform.io/builtin/... namespace so it's easier to see that they are special, and currently there is only one built-in provider named "terraform". Previous commits established the addressing scheme for built-in providers. This commit makes the installer aware of them to the extent that it knows not to try to install them the usual way and it's able to report an error if the user requests a built-in provider that doesn't exist or tries to impose a particular version constraint for a built-in provider. For the moment the tests for this are the ones in the "command" package because that's where the existing testing infrastructure for this functionality lives. A later commit should add some more focused unit tests here in the internal/providercache package, too.	6 years ago
Martin Atkins	c4fb22863c	command/init: Support -plugin-dir again ... This is a slightly different approach than we used to take for this option: rather than disabling the installer and causing all future commands to look elsewhere for plugins, we'll now leave the installer enabled by constrain it to only look at the given directories. This is overall simpler because it doesn't require any special tracking of the plugin directories for subsequent commands. Instead, the selections file generated by the installer will record the versions it selected from the specified directories, and we'll link them in to the local cache just as we would normally so that other commands don't need to do anything special to select the right plugins in either case.	6 years ago
Martin Atkins	549aede792	Remove terraform.ResourceProvider, use providercache.Installer instead ... Back when we first introduced provider versioning in Terraform 0.10, we did the provider version resolution in terraform.NewContext because we weren't sure yet how exactly our versioning model was going to play out (whether different versions could be selected per provider configuration, for example) and because we were building around the limitations of our existing filesystem-based plugin discovery model. However, the new installer codepath is new able to do all of the selections up front during installation, so we don't need such a heavy inversion of control abstraction to get this done: the command package can select the exact provider versions and pass their factories directly to terraform.NewContext as a simple static map. The result of this commit is that CLI commands other than "init" are now able to consume the local cache directory and selections produced by the installation process in "terraform init", passing all of the selected providers down to the terraform.NewContext function for use in implementing the main operations. This commit is just enough to get the providers passing into the terraform.Context. There's still plenty more to do here, including to repair all of the tests this change has additionally broken.	6 years ago
Martin Atkins	754b7ebb65	command: Expose providercache package objects for use elsewhere ... These new functions allow command implementations to get hold of the providercache objects and installation source object derived from the current CLI configuration.	6 years ago