Use viper to read create template params from a config

[sarataha]

Closes #2227

What changed?
Added viper to read create template params from a config file instead of setting them manually.

Why was this change made?
The command requires writing many parameters when running it.

How was this change implemented?

How did you validate the change?
Manually + unit tests.

Release notes

Documentation Changes

[foot]

✨ and with tests! ✨

[foot]

spf13/viper#411 :(, Had a quick play w/ StringToString but we end up with case-insensitive keys here which is a shame. This might be the best we can do without writing lots of parsing stuff.

[sarataha]

Not sure if we could extract these parameters from the template file and compare its lower case version to the received parameter and swap the keys, and if it's actually necessary 😅

[foot]

e.g.

diff --git a/cmd/gitops/app/create/templates/cmd.go b/cmd/gitops/app/create/templates/cmd.go
index 5b78dba1..2c32f796 100644
--- a/cmd/gitops/app/create/templates/cmd.go
+++ b/cmd/gitops/app/create/templates/cmd.go
@@ -22,10 +22,10 @@ import (
 )
 
 type Config struct {
-	ParameterValues []string `mapstructure:"values"`
-	Export          bool     `mapstructure:"export"`
-	OutputDir       string   `mapstructure:"output-dir"`
-	TemplateFile    string   `mapstructure:"template-file"`
+	ParameterValues map[string]string `mapstructure:"values"`
+	Export          bool              `mapstructure:"export"`
+	OutputDir       string            `mapstructure:"output-dir"`
+	TemplateFile    string            `mapstructure:"template-file"`
 }
 
 var config Config
@@ -49,7 +49,7 @@ var CreateCommand = &cobra.Command{
 
 func init() {
 	flags := CreateCommand.Flags()
-	flags.StringSlice("values", []string{}, "Set parameter values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)")
+	flags.StringToString("values", map[string]string{}, "Set parameter values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)")
 	flags.Bool("export", false, "export in YAML format to stdout")
 	flags.String("output-dir", "", "write YAML format to file")
 	flags.String("template-file", "", "template file to use")
@@ -102,18 +102,9 @@ func templatesCmdRunE() func(*cobra.Command, []string) error {
 		}
 
 		ctx := context.Background()
-		vals := make(map[string]string)
-
-		// parse parameter values
-		for _, v := range config.ParameterValues {
-			kv := strings.SplitN(v, "=", 2)
-			if len(kv) == 2 {
-				vals[kv[0]] = kv[1]
-			}
-		}
 
 		getFilesRequest := server.GetFilesRequest{
-			ParameterValues: vals,
+			ParameterValues: config.ParameterValues,
 			TemplateName:    parsedTemplate.Name,
 			TemplateKind:    parsedTemplate.Kind,
 		}
diff --git a/cmd/gitops/app/create/templates/cmd_test.go b/cmd/gitops/app/create/templates/cmd_test.go
index e95e4cf1..6a3294f9 100644
--- a/cmd/gitops/app/create/templates/cmd_test.go
+++ b/cmd/gitops/app/create/templates/cmd_test.go
@@ -106,9 +106,14 @@ func Test_initializeConfig(t *testing.T) {
 
 	assert.Equal(t, config.TemplateFile, "template.yaml")
 
-	expectedParams := []string{
-		"CLUSTER_NAME=test-cluster", "RESOURCE_NAME=test-resource", "NAMESPACE=test-namespace",
-		"GIT_REPO_NAMESPACE=test-git-repo-namespace", "GIT_REPO_NAME=test-git-repo-name", "PATH=../clusters/out.yaml"}
+	expectedParams := map[string]string{
+		"CLUSTER_NAME":       "test-cluster",
+		"RESOURCE_NAME":      "test-resource",
+		"NAMESPACE":          "test-namespace",
+		"GIT_REPO_NAMESPACE": "test-git-repo-namespace",
+		"GIT_REPO_NAME":      "test-git-repo-name",
+		"PATH":               "../clusters/out.yaml",
+	}
 
 	if diff := cmp.Diff(expectedParams, config.ParameterValues); diff != "" {
 		t.Fatalf("result didn't match expected:\n%s", diff)
diff --git a/cmd/gitops/app/create/templates/testdata/config.yaml b/cmd/gitops/app/create/templates/testdata/config.yaml
index ef47dd7e..a4b9ee85 100644
--- a/cmd/gitops/app/create/templates/testdata/config.yaml
+++ b/cmd/gitops/app/create/templates/testdata/config.yaml
@@ -1,8 +1,8 @@
 template-file: template.yaml
 values:
-  - CLUSTER_NAME=test-cluster
-  - RESOURCE_NAME=test-resource
-  - NAMESPACE=test-namespace
-  - GIT_REPO_NAMESPACE=test-git-repo-namespace
-  - GIT_REPO_NAME=test-git-repo-name
-  - PATH=../clusters/out.yaml
\ No newline at end of file
+  CLUSTER_NAME: test-cluster
+  RESOURCE_NAME: test-resource
+  NAMESPACE: test-namespace
+  GIT_REPO_NAMESPACE: test-git-repo-namespace
+  GIT_REPO_NAME: test-git-repo-name
+  PATH: ../clusters/out.yaml

Fails with:

Error: must specify template file
--- FAIL: Test_initializeConfig (0.00s)
    /Users/simon/weave/weave-gitops-enterprise/cmd/gitops/app/create/templates/cmd_test.go:119: result didn't match expected:
          map[string]string{
        - 	"CLUSTER_NAME":       "test-cluster",
        - 	"GIT_REPO_NAME":      "test-git-repo-name",
        - 	"GIT_REPO_NAMESPACE": "test-git-repo-namespace",
        - 	"NAMESPACE":          "test-namespace",
        - 	"PATH":               "../clusters/out.yaml",
        - 	"RESOURCE_NAME":      "test-resource",
        + 	"cluster_name":       "test-cluster",
        + 	"git_repo_name":      "test-git-repo-name",
        + 	"git_repo_namespace": "test-git-repo-namespace",
        + 	"namespace":          "test-namespace",
        + 	"path":               "../clusters/out.yaml",
        + 	"resource_name":      "test-resource",
          }
FAIL
coverage: 42.0% of statements
FAIL	github.com/weaveworks/weave-gitops-enterprise/cmd/gitops/app/create/templates	0.450s
FAIL

[foot]

So still LGTM! 🎉