Pass --keep-history when so instructed [#24]

README.md

@@ -65,6 +65,7 @@ drone-helm3 is largely backwards-compatible with drone-helm. There are some know
 * You'll need to migrate the deployments in the cluster [helm-v2-to-helm-v3](https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/).
 * EKS is not supported. See [#5](https://github.com/pelotech/drone-helm3/issues/5) for more information.
 * The `prefix` setting is no longer supported. If you were relying on the `prefix` setting with `secrets: [...]`, you'll need to switch to the `from_secret` syntax.
+* During uninstallations, the release history is purged by default. Use `keep_history: true` to return to the old behavior.
 * Several settings no longer have any effect. The plugin will produce warnings if any of these are present:
     * `purge` -- this is the default behavior in Helm 3
     * `recreate_pods`

docs/parameter_reference.md

@@ -54,6 +54,7 @@ Uninstallations are triggered when the `helm_command` setting is "uninstall" or
 | kubernetes_token       | string   | yes      | Token for authenticating to Kubernetes. |
 | service_account        | string   |          | Service account for authenticating to Kubernetes. Default is `helm`. |
 | kubernetes_certificate | string   |          | Base64 encoded TLS certificate used by the Kubernetes cluster's certificate authority. |
+| keep_history           | boolean  |          | Pass `--keep-history` to `helm uninstall`, to retain the release history. |
 | dry_run                | boolean  |          | Pass `--dry-run` to `helm uninstall`. |
 | timeout                | duration |          | Timeout for any *individual* Kubernetes operation. The uninstallation's full runtime may exceed this duration. |
 | skip_tls_verify        | boolean  |          | Connect to the Kubernetes cluster without checking for a valid TLS certificate. Not recommended in production. |

internal/helm/config.go

@@ -38,6 +38,7 @@ type Config struct {
 	DryRun             bool     `split_words:"true"`                 // Pass --dry-run to applicable helm commands
 	Wait               bool     ``                                   // Pass --wait to applicable helm commands
 	ReuseValues        bool     `split_words:"true"`                 // Pass --reuse-values to `helm upgrade`
+	KeepHistory        bool     `split_words:"true"`                 // Pass --keep-history to `helm uninstall`
 	Timeout            string   ``                                   // Argument to pass to --timeout in applicable helm commands
 	Chart              string   ``                                   // Chart argument to use in applicable helm commands
 	Release            string   ``                                   // Release argument to use in applicable helm commands

internal/helm/plan.go

@@ -122,6 +122,7 @@ var uninstall = func(cfg Config) []Step {
 	steps = append(steps, &run.Uninstall{
 		Release:     cfg.Release,
 		DryRun:      cfg.DryRun,
+		KeepHistory: cfg.KeepHistory,
 	})
 
 	return steps

internal/helm/plan_test.go

@@ -198,6 +198,7 @@ func (suite *PlanTestSuite) TestUninstall() {
 		DryRun:         true,
 		Timeout:        "think about what you did",
 		Release:        "jetta_id_love_to_change_the_world",
+		KeepHistory:    true,
 	}
 
 	steps := uninstall(cfg)
@@ -222,6 +223,7 @@ func (suite *PlanTestSuite) TestUninstall() {
 	expected = &run.Uninstall{
 		Release:     "jetta_id_love_to_change_the_world",
 		DryRun:      true,
+		KeepHistory: true,
 	}
 	suite.Equal(expected, actual)
 }

internal/run/uninstall.go

@@ -8,6 +8,7 @@ import (
 type Uninstall struct {
 	Release     string
 	DryRun      bool
+	KeepHistory bool
 	cmd         cmd
 }
 
@@ -36,6 +37,9 @@ func (u *Uninstall) Prepare(cfg Config) error {
 	if u.DryRun {
 		args = append(args, "--dry-run")
 	}
+	if u.KeepHistory {
+		args = append(args, "--keep-history")
+	}
 
 	args = append(args, u.Release)
 

internal/run/uninstall_test.go

@@ -81,6 +81,21 @@ func (suite *UninstallTestSuite) TestPrepareDryRunFlag() {
 	suite.Equal(expected, suite.actualArgs)
 }
 
+func (suite *UninstallTestSuite) TestPrepareKeepHistoryFlag() {
+	u := Uninstall{
+		Release:     "perturbator_sentient",
+		KeepHistory: true,
+	}
+	cfg := Config{}
+
+	suite.mockCmd.EXPECT().Stdout(gomock.Any()).AnyTimes()
+	suite.mockCmd.EXPECT().Stderr(gomock.Any()).AnyTimes()
+
+	suite.NoError(u.Prepare(cfg))
+	expected := []string{"uninstall", "--keep-history", "perturbator_sentient"}
+	suite.Equal(expected, suite.actualArgs)
+}
+
 func (suite *UninstallTestSuite) TestPrepareNamespaceFlag() {
 	u := Uninstall{
 		Release: "carly_simon_run_away_with_me",