feat: run a terraform plan before creating workspaces with the given template parameters (#1732)

coderd/database/dump.sql

@@ -50,7 +50,8 @@ CREATE TYPE parameter_type_system AS ENUM (
 
 CREATE TYPE provisioner_job_type AS ENUM (
     'template_version_import',
-    'workspace_build'
+    'workspace_build',
+    'template_version_dry_run'
 );
 
 CREATE TYPE provisioner_storage_method AS ENUM (

coderd/database/migrations/000099_provisioner_job_type_dry_run.down.sql

@@ -0,0 +1,9 @@
+-- It's not possible to drop enum values from enum types, so the UP has "IF NOT
+-- EXISTS".
+
+-- Delete all jobs that use the new enum value.
+DELETE FROM
+    provisioner_jobs
+WHERE
+    type = 'template_version_dry_run'
+;

coderd/database/migrations/000099_provisioner_job_type_dry_run.up.sql

@@ -0,0 +1,2 @@
+ALTER TYPE provisioner_job_type
+ADD VALUE IF NOT EXISTS 'template_version_dry_run';

coderd/database/models.go

@@ -179,6 +179,7 @@ type ProvisionerJobType string
 const (
 	ProvisionerJobTypeTemplateVersionImport ProvisionerJobType = "template_version_import"
 	ProvisionerJobTypeWorkspaceBuild        ProvisionerJobType = "workspace_build"
+	ProvisionerJobTypeTemplateVersionDryRun ProvisionerJobType = "template_version_dry_run"
 )
 
 func (e *ProvisionerJobType) Scan(src interface{}) error {