Add support for helm templates

Add support for evaluating helm templates
The interface provides a way to get a map which
contains a mapping from kubernetes kind to the
corresponding yaml file that defines a resource
of that kind. This map is then provided to the
instantiation code at instantiation time to create
in the kubernetes cluster.
P5: Use filepath.join instead of strings.join
P9: rebase with new folder structure
P10: moved the helm code into its own package.
P12: Add unit tests
     update the go.mod to use latest docker version

Issue-ID: MULTICLOUD-291
Change-Id: Ie75f5c616cc0cdc3e0ace49ff2c2f6c356a4c0d1
Signed-off-by: Kiran Kamineni <kiran.k.kamineni@intel.com>

1 files changed, 195 insertions, 0 deletions

diff --git a/src/k8splugin/internal/helm/helm_test.go b/src/k8splugin/internal/helm/helm_test.go
new file mode 100644
index 00000000..a5bcd9c8
--- /dev/null
+++ b/src/k8splugin/internal/helm/helm_test.go
@@ -0,0 +1,195 @@
+// +build unit
+
+/*
+ * Copyright 2018 Intel Corporation, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package helm
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestProcessValues(t *testing.T) {
+
+	chartDir := "../../mock_files/mock_charts/testchart1"
+	profileDir := "../../mock_files/mock_profiles/profile1"
+
+	testCases := []struct {
+		label         string
+		valueFiles    []string
+		values        []string
+		expectedHash  string
+		expectedError string
+	}{
+		{
+			label: "Process Values with Value Files Override",
+			valueFiles: []string{
+				filepath.Join(chartDir, "values.yaml"),
+				filepath.Join(profileDir, "override_values.yaml"),
+			},
+			//Hash of a combined values.yaml file that is expected
+			expectedHash:  "c18a70f426933de3c051c996dc34fd537d0131b2d13a2112a2ecff674db6c2f9",
+			expectedError: "",
+		},
+		{
+			label: "Process Values with Values Pair Override",
+			valueFiles: []string{
+				filepath.Join(chartDir, "values.yaml"),
+			},
+			//Use the same convention as specified in helm template --set
+			values: []string{
+				"service.externalPort=82",
+			},
+			//Hash of a combined values.yaml file that is expected
+			expectedHash:  "028a3521fc9f8777ea7e67a6de0c51f2c875b88ca91734999657f0ca924ddb7a",
+			expectedError: "",
+		},
+		{
+			label: "Process Values with Both Overrides",
+			valueFiles: []string{
+				filepath.Join(chartDir, "values.yaml"),
+				filepath.Join(profileDir, "override_values.yaml"),
+			},
+			//Use the same convention as specified in helm template --set
+			//Key takes precedence over the value from override_values.yaml
+			values: []string{
+				"service.externalPort=82",
+			},
+			//Hash of a combined values.yaml file that is expected
+			expectedHash:  "516fab4ab7b76ba2ff35a97c2a79b74302543f532857b945f2fe25e717e755be",
+			expectedError: "",
+		},
+	}
+
+	h := sha256.New()
+
+	for _, testCase := range testCases {
+		t.Run(testCase.label, func(t *testing.T) {
+			tc := NewTemplateClient("1.12.3", "testnamespace", "testreleasename")
+			out, err := tc.processValues(testCase.valueFiles, testCase.values)
+			if err != nil {
+				if testCase.expectedError == "" {
+					t.Fatalf("Got an error %s", err)
+				}
+				if strings.Contains(err.Error(), testCase.expectedError) == false {
+					t.Fatalf("Got unexpected error message %s", err)
+				}
+			} else {
+				//Compute the hash of returned data and compare
+				h.Write(out)
+				gotHash := fmt.Sprintf("%x", h.Sum(nil))
+				h.Reset()
+				if gotHash != testCase.expectedHash {
+					t.Fatalf("Got unexpected values.yaml %s", out)
+				}
+			}
+		})
+	}
+}
+
+func TestGenerateKubernetesArtifacts(t *testing.T) {
+
+	chartDir := "../../mock_files/mock_charts/testchart1"
+	profileDir := "../../mock_files/mock_profiles/profile1"
+
+	testCases := []struct {
+		label           string
+		chartPath       string
+		valueFiles      []string
+		values          []string
+		expectedHashMap map[string]string
+		expectedError   string
+	}{
+		{
+			label:      "Generate artifacts without any overrides",
+			chartPath:  chartDir,
+			valueFiles: []string{},
+			values:     []string{},
+			//sha256 hash of the evaluated templates in each chart
+			expectedHashMap: map[string]string{
+				"testchart1/templates/service.yaml": "bbd7257d1f6ab958680e642a8fbbbea2002ebbaa9276fb51fbd71b4b66a772cc",
+				"subcharta/templates/service.yaml":  "570389588fffdb7193ab265888d781f3d751f3a40362533344f9aa7bb93a8bb0",
+				"subchartb/templates/service.yaml":  "5654e03d922e8ec49649b4bbda9dfc9e643b3b7c9c18b602cc7e26fd36a39c2a",
+			},
+			expectedError: "",
+		},
+		{
+			label:     "Generate artifacts with overrides",
+			chartPath: chartDir,
+			valueFiles: []string{
+				filepath.Join(profileDir, "override_values.yaml"),
+			},
+			values: []string{
+				"service.externalPort=82",
+			},
+			//sha256 hash of the evaluated templates in each chart
+			expectedHashMap: map[string]string{
+				"testchart1/templates/service.yaml": "4c5aa5d38b763fe4730fc31a759c40566a99a9c51f5e0fc7f93473c9affc2ca8",
+				"subcharta/templates/service.yaml":  "570389588fffdb7193ab265888d781f3d751f3a40362533344f9aa7bb93a8bb0",
+				"subchartb/templates/service.yaml":  "5654e03d922e8ec49649b4bbda9dfc9e643b3b7c9c18b602cc7e26fd36a39c2a",
+			},
+			expectedError: "",
+		},
+	}
+
+	h := sha256.New()
+
+	for _, testCase := range testCases {
+		t.Run(testCase.label, func(t *testing.T) {
+			tc := NewTemplateClient("1.12.3", "testnamespace", "testreleasename")
+			out, err := tc.GenerateKubernetesArtifacts(testCase.chartPath, testCase.valueFiles,
+				testCase.values)
+			if err != nil {
+				if testCase.expectedError == "" {
+					t.Fatalf("Got an error %s", err)
+				}
+				if strings.Contains(err.Error(), testCase.expectedError) == false {
+					t.Fatalf("Got unexpected error message %s", err)
+				}
+			} else {
+				//Compute the hash of returned data and compare
+				for _, v := range out {
+					for _, f := range v {
+						data, err := ioutil.ReadFile(f)
+						if err != nil {
+							t.Errorf("Unable to read file %s", v)
+						}
+						h.Write(data)
+						gotHash := fmt.Sprintf("%x", h.Sum(nil))
+						h.Reset()
+
+						//Find the right hash from expectedHashMap
+						expectedHash := ""
+						for k1, v1 := range testCase.expectedHashMap {
+							if strings.Contains(f, k1) == true {
+								expectedHash = v1
+								break
+							}
+						}
+						if gotHash != expectedHash {
+							t.Fatalf("Got unexpected hash for %s", f)
+						}
+					}
+				}
+			}
+		})
+	}
+}