feat(tests): Allow to provision memory driver

The memory driver is used for go tests. It can also be used from the
command-line by setting the environment variable HELM_DRIVER=memory.
In the latter case however, there was no way to pre-provision some
releases.

This commit introduces the HELM_MEMORY_DRIVER_DATA variable which
can be used to provide a colon-separated list of yaml files specifying
releases to provision automatically.

For example:
   HELM_DRIVER=memory \
   HELM_MEMORY_DRIVER_DATA=./testdata/releases.yaml \
   helm list --all-namespaces

Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca>

cmd/helm/helm.go

@@ -19,6 +19,7 @@ package main // import "helm.sh/helm/v3/cmd/helm"
 import (
 	"flag"
 	"fmt"
+	"io/ioutil"
 	"log"
 	"os"
 	"strings"
@@ -26,6 +27,7 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 	"k8s.io/klog"
+	"sigs.k8s.io/yaml"
 
 	// Import to initialize client auth plugins.
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
@@ -34,6 +36,9 @@ import (
 	"helm.sh/helm/v3/pkg/action"
 	"helm.sh/helm/v3/pkg/cli"
 	"helm.sh/helm/v3/pkg/gates"
+	kubefake "helm.sh/helm/v3/pkg/kube/fake"
+	"helm.sh/helm/v3/pkg/release"
+	"helm.sh/helm/v3/pkg/storage/driver"
 )
 
 // FeatureGateOCI is the feature gate for checking if `helm chart` and `helm registry` commands should work
@@ -78,9 +83,13 @@ func main() {
 		}
 	}
 
-	if err := actionConfig.Init(settings.RESTClientGetter(), settings.Namespace(), os.Getenv("HELM_DRIVER"), debug); err != nil {
+	helmDriver := os.Getenv("HELM_DRIVER")
+	if err := actionConfig.Init(settings.RESTClientGetter(), settings.Namespace(), helmDriver, debug); err != nil {
 		log.Fatal(err)
 	}
+	if helmDriver == "memory" {
+		loadReleasesInMemory(actionConfig)
+	}
 
 	if err := cmd.Execute(); err != nil {
 		debug("%+v", err)
@@ -106,3 +115,41 @@ func checkOCIFeatureGate() func(_ *cobra.Command, _ []string) error {
 		return nil
 	}
 }
+
+// This function loads releases into the memory storage if the
+// environment variable is properly set.
+func loadReleasesInMemory(actionConfig *action.Configuration) {
+	filePaths := strings.Split(os.Getenv("HELM_MEMORY_DRIVER_DATA"), ":")
+	if len(filePaths) == 0 {
+		return
+	}
+
+	store := actionConfig.Releases
+	mem, ok := store.Driver.(*driver.Memory)
+	if !ok {
+		// For an unexpected reason we are not dealing with the memory storage driver.
+		return
+	}
+
+	actionConfig.KubeClient = &kubefake.PrintingKubeClient{Out: ioutil.Discard}
+
+	for _, path := range filePaths {
+		b, err := ioutil.ReadFile(path)
+		if err != nil {
+			log.Fatal("Unable to read memory driver data", err)
+		}
+
+		releases := []*release.Release{}
+		if err := yaml.Unmarshal(b, &releases); err != nil {
+			log.Fatal("Unable to unmarshal memory driver data: ", err)
+		}
+
+		for _, rel := range releases {
+			if err := store.Create(rel); err != nil {
+				log.Fatal(err)
+			}
+		}
+	}
+	// Must reset namespace to the proper one
+	mem.SetNamespace(settings.Namespace())
+}

pkg/action/action.go

@@ -241,7 +241,18 @@ func (c *Configuration) Init(getter genericclioptions.RESTClientGetter, namespac
 		d.Log = log
 		store = storage.Init(d)
 	case "memory":
-		d := driver.NewMemory()
+		var d *driver.Memory
+		if c.Releases != nil {
+			if mem, ok := c.Releases.Driver.(*driver.Memory); ok {
+				// This function can be called more than once (e.g., helm list --all-namespaces).
+				// If a memory driver was already initialized, re-use it but set the possibly new namespace.
+				// We re-use it in case some releases where already created in the existing memory driver.
+				d = mem
+			}
+		}
+		if d == nil {
+			d = driver.NewMemory()
+		}
 		d.SetNamespace(namespace)
 		store = storage.Init(d)
 	default:

testdata/releases.yaml

@@ -0,0 +1,43 @@
+# This file can be used as input to create test releases:
+# HELM_MEMORY_DRIVER_DATA=./testdata/releases.yaml HELM_DRIVER=memory helm list --all-namespaces
+- name: athos
+  version: 1
+  namespace: default
+  info:
+    status: deployed
+  chart:
+    metadata:
+      name: athos-chart
+      version: 1.0.0
+      appversion: 1.1.0
+- name: porthos
+  version: 2
+  namespace: default
+  info:
+    status: deployed
+  chart:
+    metadata:
+      name: prothos-chart
+      version: 0.2.0
+      appversion: 0.2.2
+- name: aramis
+  version: 3
+  namespace: default
+  info:
+    status: deployed
+  chart:
+    metadata:
+      name: aramis-chart
+      version: 0.0.3
+      appversion: 3.0.3
+- name: dartagnan
+  version: 4
+  namespace: gascony
+  info:
+    status: deployed
+  chart:
+    metadata:
+      name: dartagnan-chart
+      version: 0.4.4
+      appversion: 4.4.4
+