feat: Add coder_provisioner resource for attributes from the host (#36

)

* feat: Add `coder_host` resource for attributes from the host

Our [Docker template](https://github.com/coder/coder/blob/main/examples/templates/docker/main.tf#L16-L60) exposes variables
which are easily obtainable from the host. By adding this resource, we allow simple setups that depend on host
architecture to work without input from the user.

* Update internal/provider/provider.go

Co-authored-by: Ben Potter <me@bpmct.net>

Co-authored-by: Ben Potter <me@bpmct.net>

docs/data-sources/provisioner.md

@@ -0,0 +1,24 @@
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "coder_provisioner Data Source - terraform-provider-coder"
+subcategory: ""
+description: |-
+  Use this data source to get information about the Coder provisioner.
+---
+
+# coder_provisioner (Data Source)
+
+Use this data source to get information about the Coder provisioner.
+
+
+
+<!-- schema generated by tfplugindocs -->
+## Schema
+
+### Read-Only
+
+- `arch` (String) The architecture of the host. This exposes `runtime.GOARCH` (see https://pkg.go.dev/runtime#pkg-constants).
+- `id` (String) The ID of this resource.
+- `os` (String) The operating system of the host. This exposes `runtime.GOOS` (see https://pkg.go.dev/runtime#pkg-constants).
+
+

internal/provider/provider.go

@@ -7,6 +7,7 @@ import (
 	"net/url"
 	"os"
 	"reflect"
+	"runtime"
 	"strings"
 
 	"github.com/google/uuid"
@@ -150,6 +151,28 @@ func New() *schema.Provider {
 					},
 				},
 			},
+			"coder_provisioner": {
+				Description: "Use this data source to get information about the Coder provisioner.",
+				ReadContext: func(c context.Context, rd *schema.ResourceData, i interface{}) diag.Diagnostics {
+					rd.SetId(uuid.NewString())
+					rd.Set("os", runtime.GOOS)
+					rd.Set("arch", runtime.GOARCH)
+
+					return nil
+				},
+				Schema: map[string]*schema.Schema{
+					"os": {
+						Type:        schema.TypeString,
+						Computed:    true,
+						Description: "The operating system of the host. This exposes `runtime.GOOS` (see https://pkg.go.dev/runtime#pkg-constants).",
+					},
+					"arch": {
+						Type:        schema.TypeString,
+						Computed:    true,
+						Description: "The architecture of the host. This exposes `runtime.GOARCH` (see https://pkg.go.dev/runtime#pkg-constants).",
+					},
+				},
+			},
 		},
 		ResourcesMap: map[string]*schema.Resource{
 			"coder_agent": {

internal/provider/provider_test.go

@@ -1,6 +1,7 @@
 package provider_test
 
 import (
+	"runtime"
 	"testing"
 
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/resource"
@@ -52,6 +53,33 @@ func TestWorkspace(t *testing.T) {
 	})
 }
 
+func TestProvisioner(t *testing.T) {
+	resource.Test(t, resource.TestCase{
+		Providers: map[string]*schema.Provider{
+			"coder": provider.New(),
+		},
+		IsUnitTest: true,
+		Steps: []resource.TestStep{{
+			Config: `
+			provider "coder" {
+			}
+			data "coder_provisioner" "me" {
+			}`,
+			Check: func(state *terraform.State) error {
+				require.Len(t, state.Modules, 1)
+				require.Len(t, state.Modules[0].Resources, 1)
+				resource := state.Modules[0].Resources["data.coder_provisioner.me"]
+				require.NotNil(t, resource)
+
+				attribs := resource.Primary.Attributes
+				require.Equal(t, runtime.GOOS, attribs["os"])
+				require.Equal(t, runtime.GOARCH, attribs["arch"])
+				return nil
+			},
+		}},
+	})
+}
+
 func TestAgent(t *testing.T) {
 	t.Parallel()
 	resource.Test(t, resource.TestCase{