Add tests of multicluster install command (#7111)

Currently there are no tests of the output of the multicluster install command unlike the install and viz install commands. This makes it error prone to hard to validate changes. This is motivated by the addition of an ha mode to the multicluster components discussed in #7082. This change adds two test cases and refactors the install command to look like viz install making it easily testable. This means in practice that the body of the command is moved into an install function. Here we extract external data, eg. values, and delegates the values to a render function that handles the actual rendering. This is a non-functional change and the output used for the install_default.golden file is based of the main branch to validate this. Signed-off-by: Crevil <[email protected]> (cherry picked from commit fddfb74) Signed-off-by: Oliver Gould <[email protected]>
linkerd · Apr 14, 2022 · 1bc71f3 · 1bc71f3
1 parent 3daec14
commit 1bc71f3
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Showing 5 changed files with 922 additions and 83 deletions.
diff --git a/multicluster/cmd/install.go b/multicluster/cmd/install.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"os"
 	"path"
 	"time"
@@ -68,89 +69,7 @@ A full list of configurable values can be found at https://github.com/linkerd/li
 				APIAddr:               apiAddr,
 				RetryDeadline:         time.Now().Add(wait),
 			})
-
-			values, err := buildMulticlusterInstallValues(cmd.Context(), options)
-
-			if err != nil {
-				return err
-			}
-
-			// Render raw values and create chart config
-			rawValues, err := yaml.Marshal(values)
-			if err != nil {
-				return err
-			}
-
-			files := []*chartloader.BufferedFile{
-				{Name: chartutil.ChartfileName},
-				{Name: "templates/namespace.yaml"},
-				{Name: "templates/gateway.yaml"},
-				{Name: "templates/proxy-admin-policy.yaml"},
-				{Name: "templates/gateway-policy.yaml"},
-				{Name: "templates/psp.yaml"},
-				{Name: "templates/remote-access-service-mirror-rbac.yaml"},
-				{Name: "templates/link-crd.yaml"},
-				{Name: "templates/service-mirror-policy.yaml"},
-			}
-
-			var partialFiles []*loader.BufferedFile
-			for _, template := range charts.L5dPartials {
-				partialFiles = append(partialFiles,
-					&loader.BufferedFile{Name: template},
-				)
-			}
-
-			// Load all multicluster install chart files into buffer
-			if err := charts.FilesReader(static.Templates, helmMulticlusterDefaultChartName+"/", files); err != nil {
-				return err
-			}
-
-			// Load all partial chart files into buffer
-			if err := charts.FilesReader(partials.Templates, "", partialFiles); err != nil {
-				return err
-			}
-
-			// Create a Chart obj from the files
-			chart, err := loader.LoadFiles(append(files, partialFiles...))
-			if err != nil {
-				return err
-			}
-
-			// Store final Values generated from values.yaml and CLI flags
-			err = yaml.Unmarshal(rawValues, &chart.Values)
-			if err != nil {
-				return err
-			}
-
-			// Create values override
-			valuesOverrides, err := valuesOptions.MergeValues(nil)
-			if err != nil {
-				return err
-			}
-
-			vals, err := chartutil.CoalesceValues(chart, valuesOverrides)
-			if err != nil {
-				return err
-			}
-
-			// Attach the final values into the `Values` field for rendering to work
-			renderedTemplates, err := engine.Render(chart, map[string]interface{}{"Values": vals})
-			if err != nil {
-				return err
-			}
-
-			// Merge templates and inject
-			var buf bytes.Buffer
-			for _, tmpl := range chart.Templates {
-				t := path.Join(chart.Metadata.Name, tmpl.Name)
-				if _, err := buf.WriteString(renderedTemplates[t]); err != nil {
-					return err
-				}
-			}
-			stdout.Write(buf.Bytes())
-			stdout.Write([]byte("---\n"))
-
-			return nil
+			return install(cmd.Context(), stdout, options, valuesOptions)
 		},
 	}
 
@@ -178,6 +97,94 @@ A full list of configurable values can be found at https://github.com/linkerd/li
 	return cmd
 }
 
+func install(ctx context.Context, w io.Writer, options *multiclusterInstallOptions, valuesOptions valuespkg.Options) error {
+	values, err := buildMulticlusterInstallValues(ctx, options)
+	if err != nil {
+		return err
+	}
+
+	// Create values override
+	valuesOverrides, err := valuesOptions.MergeValues(nil)
+	if err != nil {
+		return err
+	}
+
+	return render(w, values, valuesOverrides)
+}
+
+func render(w io.Writer, values *multicluster.Values, valuesOverrides map[string]interface{}) error {
+	files := []*chartloader.BufferedFile{
+		{Name: chartutil.ChartfileName},
+		{Name: chartutil.ValuesfileName},
+		{Name: "templates/namespace.yaml"},
+		{Name: "templates/gateway.yaml"},
+		{Name: "templates/proxy-admin-policy.yaml"},
+		{Name: "templates/gateway-policy.yaml"},
+		{Name: "templates/psp.yaml"},
+		{Name: "templates/remote-access-service-mirror-rbac.yaml"},
+		{Name: "templates/link-crd.yaml"},
+		{Name: "templates/service-mirror-policy.yaml"},
+	}
+
+	var partialFiles []*loader.BufferedFile
+	for _, template := range charts.L5dPartials {
+		partialFiles = append(partialFiles,
+			&loader.BufferedFile{Name: template},
+		)
+	}
+
+	// Load all multicluster install chart files into buffer
+	if err := charts.FilesReader(static.Templates, helmMulticlusterDefaultChartName+"/", files); err != nil {
+		return err
+	}
+
+	// Load all partial chart files into buffer
+	if err := charts.FilesReader(partials.Templates, "", partialFiles); err != nil {
+		return err
+	}
+
+	// Create a Chart obj from the files
+	chart, err := loader.LoadFiles(append(files, partialFiles...))
+	if err != nil {
+		return err
+	}
+
+	// Render raw values and create chart config
+	rawValues, err := yaml.Marshal(values)
+	if err != nil {
+		return err
+	}
+	// Store final Values generated from values.yaml and CLI flags
+	err = yaml.Unmarshal(rawValues, &chart.Values)
+	if err != nil {
+		return err
+	}
+
+	vals, err := chartutil.CoalesceValues(chart, valuesOverrides)
+	if err != nil {
+		return err
+	}
+
+	// Attach the final values into the `Values` field for rendering to work
+	renderedTemplates, err := engine.Render(chart, map[string]interface{}{"Values": vals})
+	if err != nil {
+		return err
+	}
+
+	// Merge templates and inject
+	var buf bytes.Buffer
+	for _, tmpl := range chart.Templates {
+		t := path.Join(chart.Metadata.Name, tmpl.Name)
+		if _, err := buf.WriteString(renderedTemplates[t]); err != nil {
+			return err
+		}
+	}
+	w.Write(buf.Bytes())
+	w.Write([]byte("---\n"))
+
+	return nil
+}
+
 func newMulticlusterInstallOptionsWithDefault() (*multiclusterInstallOptions, error) {
 	defaults, err := multicluster.NewInstallValues()
 	if err != nil {

diff --git a/multicluster/cmd/install_test.go b/multicluster/cmd/install_test.go
@@ -0,0 +1,46 @@
+package cmd
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	multicluster "github.com/linkerd/linkerd2/multicluster/values"
+	"github.com/linkerd/linkerd2/pkg/charts"
+)
+
+func TestRender(t *testing.T) {
+	// pin values that are changed by render functions on each test run
+	defaultValues := map[string]interface{}{}
+
+	testCases := []struct {
+		values             map[string]interface{}
+		multiclusterValues *multicluster.Values
+		goldenFileName     string
+	}{
+		{
+			nil,
+			nil,
+			"install_default.golden",
+		},
+		{
+			map[string]interface{}{
+				"enablePSP": "true",
+			},
+			nil,
+			"install_psp.golden",
+		},
+	}
+
+	for i, tc := range testCases {
+		tc := tc // pin
+		t.Run(fmt.Sprintf("%d: %s", i, tc.goldenFileName), func(t *testing.T) {
+			var buf bytes.Buffer
+			// Merge overrides with default
+			if err := render(&buf, tc.multiclusterValues, charts.MergeMaps(defaultValues, tc.values)); err != nil {
+				t.Fatalf("Failed to render templates: %v", err)
+			}
+			testDataDiffer.DiffTestdata(t, tc.goldenFileName, buf.String())
+		})
+	}
+}
diff --git a/multicluster/cmd/main_test.go b/multicluster/cmd/main_test.go
@@ -0,0 +1,23 @@
+package cmd
+
+import (
+	"flag"
+	"os"
+	"testing"
+
+	"github.com/linkerd/linkerd2/testutil"
+)
+
+var (
+	testDataDiffer testutil.TestDataDiffer
+)
+
+// TestMain parses flags before running tests
+func TestMain(m *testing.M) {
+	flag.BoolVar(&testDataDiffer.UpdateFixtures, "update", false, "update text fixtures in place")
+	prettyDiff := os.Getenv("LINKERD_TEST_PRETTY_DIFF") != ""
+	flag.BoolVar(&testDataDiffer.PrettyDiff, "pretty-diff", prettyDiff, "display the full text when diffing")
+	flag.StringVar(&testDataDiffer.RejectPath, "reject-path", "", "write results for failed tests to this path (path is relative to the test location)")
+	flag.Parse()
+	os.Exit(m.Run())
+}