Merge pull request #49 from UKHomeOffice/split

A couple of features

README.md

@@ -73,11 +73,48 @@ $ kd --context=mykube --namespace=testing --file nginx-deployment.yaml
 
 You can fail an ongoing deployment if there's been a new deployment by adding `--fail-superseded` flag.
 
+
+## Templating
+
+### split
+
+`split` function is go's `strings.Split()`, it returns a `[]string`. A range function
+can also be used to iterate over returned list.
+
+```yaml
+# split.yaml
+---
+apiVersion: v1
+data:
+  foo: {{ split .LIST " "}}
+kind: ConfigMap
+metadata:
+  name: list
+```
+
+```
+$ export LIST="one,two,three"
+$ ./kd -f split.yaml -- --dry-run -o yaml
+[INFO] 2017/10/18 15:08:09 main.go:241: deploying configmap/list
+[INFO] 2017/10/18 15:08:09 main.go:248: apiVersion: v1
+data:
+  foo:
+  - one
+  - two
+  - three
+kind: ConfigMap
+metadata:
+  name: list
+```
+
 ## Configuration
 
 Configuration can be provided via cli flags and arguments as well as
 environment variables.
 
+It supports end of flags `--` parameter, any flags or arguments that are
+specified after `--` will be passed onto kubectl.
+
 ```bash
 $ kd --help
 

main.go

@@ -179,7 +179,11 @@ func run(c *cli.Context) error {
 }
 
 func render(tmpl string, vars map[string]string) (string, error) {
-	t := template.Must(template.New("template").Parse(tmpl))
+	fm := template.FuncMap{
+		"split": strings.Split,
+	}
+
+	t := template.Must(template.New("template").Funcs(fm).Parse(tmpl))
 	t.Option("missingkey=error")
 	var b bytes.Buffer
 	if err := t.Execute(&b, vars); err != nil {
@@ -338,9 +342,29 @@ func newKubeCmd(c *cli.Context, args []string) (*exec.Cmd, error) {
 		args = append([]string{"--server=" + c.String("kube-server")}, args...)
 	}
 
+	flags, err := extraFlags(c)
+	if err != nil {
+		return nil, err
+	}
+	args = append(args, flags...)
+
 	return exec.Command(kube, args...), nil
 }
 
+func extraFlags(c *cli.Context) ([]string, error) {
+	var a []string
+
+	if c.NArg() < 1 {
+		return a, nil
+	}
+
+	if c.Args()[0] == "--" {
+		return c.Args()[1:], nil
+	}
+
+	return c.Args(), nil
+}
+
 // listDirectory returns a recursive list of all files under a directory, or an error
 func listDirectory(path string) ([]string, error) {
 	var list []string