Add support for --api-versions in helm-diff-upgrade (#329)

* Add support for --api-versions in helm-diff-upgrade

Resolves #318

* Update helm-diff-upgrade usage in README

Author: mumoshu

README.md

@@ -118,18 +118,40 @@ Usage:
 Examples:
   helm diff upgrade my-release stable/postgresql --values values.yaml
 
+  # Set HELM_DIFF_IGNORE_UNKNOWN_FLAGS=true to ignore unknown flags
+  # It's useful when you're using `helm-diff` in a `helm upgrade` wrapper.
+  HELM_DIFF_IGNORE_UNKNOWN_FLAGS=true helm diff upgrade my-release stable/postgres --wait
+
 Flags:
-  -h, --help                   help for upgrade
-      --detailed-exitcode      return a non-zero exit code when there are changes
-      --post-renderer string   the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path
-      --reset-values           reset the values to the ones built into the chart and merge in any new values
-      --reuse-values           reuse the last release's values and merge in any new values
-      --strip-trailing-cr      strip trailing carriage return on input
-      --set stringArray        set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
-      --suppress stringArray   allows suppression of the values listed in the diff output
-  -q, --suppress-secrets       suppress secrets in the output
-  -f, --values valueFiles      specify values in a YAML file (can specify multiple) (default [])
-      --version string         specify the exact chart version to use. If this is not specified, the latest version is used
+      --allow-unreleased             enables diffing of releases that are not yet deployed via Helm
+  -a, --api-versions stringArray     Kubernetes api versions used for Capabilities.APIVersions
+  -C, --context int                  output NUM lines of context around changes (default -1)
+      --detailed-exitcode            return a non-zero exit code when there are changes
+      --devel                        use development versions, too. Equivalent to version '>0.0.0-0'. If --version is set, this is ignored.
+      --disable-openapi-validation   disables rendered templates validation against the Kubernetes OpenAPI Schema
+      --disable-validation           disables rendered templates validation against the Kubernetes cluster you are currently pointing to. This is the same validation performed on an install
+      --dry-run                      disables cluster access and show diff as if it was install. Implies --install, --reset-values, and --disable-validation
+  -h, --help                         help for upgrade
+      --include-tests                enable the diffing of the helm test hooks
+      --install                      enables diffing of releases that are not yet deployed via Helm (equivalent to --allow-unreleased, added to match "helm upgrade --install" command
+      --kubeconfig string            This flag is ignored, to allow passing of this top level flag to helm
+      --no-hooks                     disable diffing of hooks
+      --normalize-manifests          normalize manifests before running diff to exclude style differences from the output
+      --output string                Possible values: diff, simple, json, template. When set to "template", use the env var HELM_DIFF_TPL to specify the template. (default "diff")
+      --post-renderer string         the path to an executable to be used for post rendering. If it exists in $PATH, the binary will be used, otherwise it will try to look for the executable at the given path
+      --repo string                  specify the chart repository url to locate the requested chart
+      --reset-values                 reset the values to the ones built into the chart and merge in any new values
+      --reuse-values                 reuse the last release's values and merge in any new values. If '--reset-values' is specified, this is ignored
+      --set stringArray              set values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
+      --set-file stringArray         set values from respective files specified via the command line (can specify multiple or separate values with commas: key1=path1,key2=path2)
+      --set-string stringArray       set STRING values on the command line (can specify multiple or separate values with commas: key1=val1,key2=val2)
+      --show-secrets                 do not redact secret values in the output
+      --strip-trailing-cr            strip trailing carriage return on input
+      --suppress stringArray         allows suppression of the values listed in the diff output
+  -q, --suppress-secrets             suppress secrets in the output
+      --three-way-merge              use three-way-merge to compute patch and generate diff output
+  -f, --values valueFiles            specify values in a YAML file (can specify multiple) (default [])
+      --version string               specify the exact chart version to use. If this is not specified, the latest version is used
 
 Global Flags:
       --no-color   remove colors from the output

cmd/helm3.go

@@ -141,6 +141,10 @@ func (d *diffCmd) template(isUpgrade bool) ([]byte, error) {
 		flags = append(flags, "--disable-openapi-validation")
 	}
 
+	for _, a := range d.extraAPIs {
+		flags = append(flags, "--api-versions", a)
+	}
+
 	args := []string{"template", d.release, d.chart}
 	args = append(args, flags...)
 	cmd := exec.Command(os.Getenv("HELM_BIN"), args...)

cmd/upgrade.go

@@ -60,6 +60,7 @@ type diffCmd struct {
 	stripTrailingCR          bool
 	normalizeManifests       bool
 	threeWayMerge            bool
+	extraAPIs                []string
 }
 
 func (d *diffCmd) isAllowUnreleased() bool {
@@ -133,6 +134,10 @@ func newChartCommand() *cobra.Command {
 	f.StringVar(&diff.chartVersion, "version", "", "specify the exact chart version to use. If this is not specified, the latest version is used")
 	f.StringVar(&diff.chartRepo, "repo", "", "specify the chart repository url to locate the requested chart")
 	f.BoolVar(&diff.detailedExitCode, "detailed-exitcode", false, "return a non-zero exit code when there are changes")
+	// See the below links for more context on when to use this flag
+	// - https://github.com/helm/helm/blob/d9ffe37d371c9d06448c55c852c800051830e49a/cmd/helm/template.go#L184
+	// - https://github.com/databus23/helm-diff/issues/318
+	f.StringArrayVarP(&diff.extraAPIs, "api-versions", "a", []string{}, "Kubernetes api versions used for Capabilities.APIVersions")
 	f.BoolP("suppress-secrets", "q", false, "suppress secrets in the output")
 	f.BoolVar(&diff.showSecrets, "show-secrets", false, "do not redact secret values in the output")
 	f.VarP(&diff.valueFiles, "values", "f", "specify values in a YAML file (can specify multiple)")