Support for Terraforming Fleet Teams (#18750)

This project adds support for terraforming teams in Fleet. If you have
100+ teams, managing them is is prone to error, mistakes, lost
configuration, and general pain. An industry standard tool like
terraform can unify this configuration as code.

In order to do this, I wrote a terraform provider that on one end talks
to the Fleet api, and on the other end implements an interface for
terraform. More information is in the README.

A small sample `main.tf` file is supplied.

---------

Co-authored-by: Brock Walters <[email protected]>

tools/terraform/.gitignore

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+provider_code_spec.json
+tf/terraformrc-dev-override

tools/terraform/Makefile

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+#! /usr/bin/env make
+#
+# While not very elegant as far as Makefiles go, this Makefile does
+# contain the basic commands to get you terraforming your FleetDM
+# teams. See the README for details.
+
+provider_code_spec.json: openapi.json
+	tfplugingen-openapi generate --config generator.yaml --output ./provider_code_spec.json ./openapi.json
+
+provider/team_resource_gen.go: provider_code_spec.json
+	tfplugingen-framework generate resources --input provider_code_spec.json --output ./provider --package provider
+
+.PHONY: install build test tidy gen plan apply
+
+gen: provider/team_resource_gen.go
+
+install: gen
+	go install ./...
+
+build: gen
+	go build ./...
+
+test: gen
+	@test -n "$(FLEETDM_APIKEY)" || (echo "FLEETDM_APIKEY is not set" && exit 1)
+	FLEETDM_URL='https://rbx.cloud.fleetdm.com' TF_ACC=1 go test ./...
+
+tidy:
+	go mod tidy
+
+plan: tf/terraformrc-dev-override
+	cd tf && TF_CLI_CONFIG_FILE=./terraformrc-dev-override terraform plan
+
+apply: tf/terraformrc-dev-override
+	cd tf && TF_CLI_CONFIG_FILE=./terraformrc-dev-override terraform apply -auto-approve
+
+tf/terraformrc-dev-override:
+	@echo "provider_installation { \\n\
+  dev_overrides { \\n\
+    \"fleetdm.com/tf/fleetdm\" = \"$$HOME/go/bin\" \\n\
+  } \\n\
+  direct {} \\n\
+}" > $@

tools/terraform/README.md

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+# Terraform Provider for FleetDM Teams
+
+This is a Terraform provider for managing FleetDM teams. When you have
+100+ teams in FleetDM, and manually managing them is not feasible. The
+primary setting of concern is the team's "agent options" which
+consists of some settings and command line flags. These (potentially
+dangerously) configure FleetDM all machines.
+
+## Usage
+
+All the interesting commands are in the Makefile. If you just want
+to use the thing, see `make install` and `make apply`.
+
+Note that if you run `terraform apply` in the `tf` directory, it won't
+work out of the box. That's because you need to set the 
+`TF_CLI_CONFIG_FILE` environment variable to point to a file that
+enables local development of this provider. The Makefile does this
+for you.
+
+Future work: actually publish this provider.
+
+## Development
+
+### Code Generation
+
+See `make gen`. It will create team_resource_gen.go, which defines
+the types that Terraform knows about. This is automatically run
+when you run `make install`.
+
+### Running locally
+
+See `make plan` and `make apply`.
+
+### Running Tests
+
+You probably guessed this.  See `make test`. Note that these tests
+require a FleetDM server to be running. The tests will create teams
+and delete them when they're done. The tests also require a valid
+FleetDM API token to be in the `FLEETDM_APIKEY` environment variable.
+
+### Debugging locally
+
+The basic idea is that you want to run the provider in a debugger.
+When terraform normally runs, it will execute the provider a few
+times in the course of operations. What you want to do instead is
+to run the provider in debug mode and tell terraform to contact it.
+
+To do this, you need to start the provider with the `-debug` flag
+inside a debugger. You'll also need to give it the FLEETDM_APIKEY
+environment variable. The provider will print out a big environment
+variable that you can copy and paste to your command line.
+
+When you run `terraform apply` or the like, you'll invoke it with
+that big environment variable. It'll look something like 
+
+```shell
+TF_REATTACH_PROVIDERS='{"fleetdm.com/tf/fleetdm":{"Protocol":"grpc","ProtocolVersion":6,"Pid":33644,"Test":true,"Addr":{"Network":"unix","String":"/var/folders/32/xw2p1jtd4w10hpnsyrb_4nmm0000gq/T/plugin771405263"}}}' terraform apply
+```
+
+With this magic, terraform will look to your provider that's running
+in a debugger. You get breakpoints and the goodness of a debugger.