Add support for globs in resource names (#21)

* Code cleanup. Add more tests.

* Document and improve the code. Fixes #17

README.md

@@ -80,13 +80,18 @@ Usage:
   kubectl-slice [flags]
 
 Examples:
-kubectl-slice -f foo.yaml -o ./ -i Pod,Namespace
+  kubectl-slice -f foo.yaml -o ./ --include-kind Pod,Namespace
+  kubectl-slice -f foo.yaml -o ./ --exclude-kind Pod
+  kubectl-slice -f foo.yaml -o ./ --exclude-name *-svc
+  kubectl-slice -f foo.yaml --exclude-name *-svc --stdout
 
 Flags:
       --dry-run                if true, no files are created, but the potentially generated files will be printed as the command output
-  -e, --exclude-kind strings   kinds to exclude in the output (singular, case insensitive); if empty, all Kubernetes object kinds are excluded
+      --exclude-kind strings   resource kind to exclude in the output (singular, case insensitive, glob supported)
+      --exclude-name strings   resource name to exclude in the output (singular, case insensitive, glob supported)
   -h, --help                   help for kubectl-slice
-  -i, --include-kind strings   kinds to include in the output (singular, case insensitive); if empty, all Kubernetes object kinds are included
+      --include-kind strings   resource kind to include in the output (singular, case insensitive, glob supported)
+      --include-name strings   resource name to include in the output (singular, case insensitive, glob supported)
   -f, --input-file string      the input file used to read the initial macro YAML file; if empty or "-", stdin is used
   -o, --output-dir string      the output directory used to output the splitted files
   -s, --skip-non-k8s           if enabled, any YAMLs that don't contain at least an "apiVersion", "kind" and "metadata.name" will be excluded from the split
@@ -113,10 +118,10 @@ Flags:
     * If the rendered file name includes a path separator, subfolders under `--output-dir` will be created.
     * If a file already exists in `--output-directory` under this generated file name, their contents will be replaced.
 * `--exclude-kind`:
-  * A case-insensitive, comma-separated list of Kubernetes object kinds to exclude from the output.
+  * A case-insensitive, comma-separated list of Kubernetes object kinds to exclude from the output. Globs are supported.
   * You can also repeat the parameter multiple times to achieve the same effect (`--exclude-kind pod --exclude-kind deployment`)
 * `--include-kind`:
-  * A case-insensitive, comma-separated list of Kubernetes object kinds to include in the output. Any other Kubernetes object kinds will be excluded.
+  * A case-insensitive, comma-separated list of Kubernetes object kinds to include in the output. Globs are supported. Any other Kubernetes object kinds will be excluded.
   * You can also repeat the parameter multiple times to achieve the same effect (`--include-kind pod --include-kind deployment`)
 * `--skip-non-k8s`:
   * If enabled, any YAMLs that don't contain at least an `apiVersion`, `kind` and `metadata.name` will be excluded from the split
@@ -127,6 +132,12 @@ Flags:
   * If this flag is not present, resources are outputted following the order in which they were found in the YAML file.
 * `--stdout`:
   * If enabled, no resource is written to disk and all resources are printed to `stdout` instead, useful if you want to pipe the output of `kubectl-slice` to another command or to itself. File names are still generated, but used as reference and prepended at the top of each file in the multi-YAML output. Other than that, the file name template has no effect -- it won't create any subfolders, for example.
+* `--include-name`:
+  * A case-insensitive, comma-separated list of Kubernetes object names to include in the output. Globs are supported. Any other Kubernetes object names will be excluded.
+  * You can also repeat the parameter multiple times to achieve the same effect (`--include-name foo --include-name bar`)
+* `--exclude-name`:
+  * A case-insensitive, comma-separated list of Kubernetes object names to exclude from the output. Globs are supported.
+  * You can also repeat the parameter multiple times to achieve the same effect (`--exclude-name foo --exclude-name bar`)
 
 ## Why `kubectl-slice`?
 
@@ -143,5 +154,4 @@ Pull requests are welcomed! So far, looking for help with the following items, w
 * Adding unit tests
 * Improving the YAML file-by-file parser, right now it works by buffering line by line
 * Adding support to install through `brew`
-* Functions to allow accessing labels and annotations on a way different than the dot-notation from Go templates
 * [Adding new features marked as `enhancement`](//github.com/patrickdappollonio/kubectl-slice/issues?q=is%3Aissue+is%3Aopen+label%3Aenhancement)

app.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"fmt"
 	"os"
 
@@ -17,6 +18,26 @@ const (
 For documentation, available functions, and more, visit: https://github.com/patrickdappollonio/kubectl-slice.`
 )
 
+var examples = []string{
+	"kubectl-slice -f foo.yaml -o ./ --include-kind Pod,Namespace",
+	"kubectl-slice -f foo.yaml -o ./ --exclude-kind Pod",
+	"kubectl-slice -f foo.yaml -o ./ --exclude-name *-svc",
+	"kubectl-slice -f foo.yaml --exclude-name *-svc --stdout",
+}
+
+func generateExamples([]string) string {
+	var s bytes.Buffer
+	for pos, v := range examples {
+		s.WriteString(fmt.Sprintf("  %s", v))
+
+		if pos != len(examples)-1 {
+			s.WriteString("\n")
+		}
+	}
+
+	return s.String()
+}
+
 func root() *cobra.Command {
 	opts := slice.Options{}
 
@@ -27,7 +48,7 @@ func root() *cobra.Command {
 		Version:       version,
 		SilenceUsage:  true,
 		SilenceErrors: true,
-		Example:       `kubectl-slice -f foo.yaml -o ./ -i Pod,Namespace`,
+		Example:       generateExamples(examples),
 		RunE: func(_ *cobra.Command, args []string) error {
 			// If no input file has been provided or it's "-", then
 			// point the app to stdin
@@ -50,8 +71,10 @@ func root() *cobra.Command {
 	rootCommand.Flags().StringVarP(&opts.GoTemplate, "template", "t", slice.DefaultTemplateName, "go template used to generate the file name when creating the resource files in the output directory")
 	rootCommand.Flags().BoolVar(&opts.DryRun, "dry-run", false, "if true, no files are created, but the potentially generated files will be printed as the command output")
 	rootCommand.Flags().BoolVar(&opts.DebugMode, "debug", false, "enable debug mode")
-	rootCommand.Flags().StringSliceVarP(&opts.IncludedKinds, "include-kind", "i", nil, "kinds to include in the output (singular, case insensitive); if empty, all Kubernetes object kinds are included")
-	rootCommand.Flags().StringSliceVarP(&opts.ExcludedKinds, "exclude-kind", "e", nil, "kinds to exclude in the output (singular, case insensitive); if empty, all Kubernetes object kinds are excluded")
+	rootCommand.Flags().StringSliceVar(&opts.IncludedKinds, "include-kind", nil, "resource kind to include in the output (singular, case insensitive, glob supported)")
+	rootCommand.Flags().StringSliceVar(&opts.ExcludedKinds, "exclude-kind", nil, "resource kind to exclude in the output (singular, case insensitive, glob supported)")
+	rootCommand.Flags().StringSliceVar(&opts.IncludedNames, "include-name", nil, "resource name to include in the output (singular, case insensitive, glob supported)")
+	rootCommand.Flags().StringSliceVar(&opts.ExcludedNames, "exclude-name", nil, "resource name to exclude in the output (singular, case insensitive, glob supported)")
 	rootCommand.Flags().BoolVarP(&opts.StrictKubernetes, "skip-non-k8s", "s", false, "if enabled, any YAMLs that don't contain at least an \"apiVersion\", \"kind\" and \"metadata.name\" will be excluded from the split")
 	rootCommand.Flags().BoolVar(&opts.SortByKind, "sort-by-kind", false, "if enabled, resources are sorted by Kind, a la Helm, before saving them to disk")
 	rootCommand.Flags().BoolVar(&opts.OutputToStdout, "stdout", false, "if enabled, no resource is written to disk and all resources are printed to stdout instead")

docs/faq.md

@@ -25,11 +25,23 @@ kubectl-slice --exclude-kind=Deployment,ReplicaSet,DaemonSet
 kubectl-slice --exclude-kind=Deployment --exclude-kind=ReplicaSet --exclude-kind=DaemonSet
 ```
 
+Additionally, you can use `--include-name` and `--exclude-name` to include or exclude resources by Kubernetes name.
+
+```bash
+kubectl-slice --exclude-name=my-deployment
+```
+
+Globs are also supported, so you can use `--include-name=foo*` to include all resources with names starting with `foo`.
+
+If a YAML resource can't be parsed to detect its name or kind, it will be included by default on any `exclude` flag.
+
+All flags are also case insensitive -- they will be converted to lowercase before applying the glob check.
+
 ## Some of the code in my YAML is an entire YAML file commented out, how do I skip it?
 
 By default, `kubectl-slice` will also slice out commented YAML file sections. If you would rather want to ensure only Kubernetes resources are sliced from the original YAML file, then there's two options:
 
-* Use `--include-kind` to only include Kubernetes resources by kind; or
+* Use `--include-kind` or `--include-name` to only include Kubernetes resources by kind or name; or
 * Use `--skip-non-k8s` to skip any non-Kubernetes resources
 
 `--include-kind` can be used so you control your entire output by specifying only the resources you want. For example, if you want to only slice out `Deployment` resources, you can use `--include-kind=Deployment`.

go.mod

@@ -9,5 +9,6 @@ require (
 
 require (
 	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/mb0/glob v0.0.0-20160210091149-1eb79d2de6c4 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 )

go.sum

@@ -175,6 +175,8 @@ github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/magiconair/properties v1.8.5/go.mod h1:y3VJvCyxH9uVvJTWEGAELF3aiYNyPKd5NZ3oSwXrF60=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
+github.com/mb0/glob v0.0.0-20160210091149-1eb79d2de6c4 h1:NK3O7S5FRD/wj7ORQ5C3Mx1STpyEMuFe+/F0Lakd1Nk=
+github.com/mb0/glob v0.0.0-20160210091149-1eb79d2de6c4/go.mod h1:FqD3ES5hx6zpzDainDaHgkTIqrPaI9uX4CVWqYZoQjY=
 github.com/miekg/dns v1.0.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
 github.com/mitchellh/cli v1.0.0/go.mod h1:hNIlj7HEI86fIcpObd7a0FcrxTWetlwJDGcceTlRvqc=
 github.com/mitchellh/go-homedir v1.0.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=

slice/errors.go

@@ -2,20 +2,21 @@ package slice
 
 import "fmt"
 
-type strictModeErr struct {
+type strictModeSkipErr struct {
 	fieldName string
 }
 
-func (s *strictModeErr) Error() string {
+func (s *strictModeSkipErr) Error() string {
 	return fmt.Sprintf(
 		"resource does not have a Kubernetes %q field or the field is invalid or empty", s.fieldName,
 	)
 }
 
-type kindSkipErr struct {
-	Kind string
+type skipErr struct {
+	name string
+	kind string
 }
 
-func (e *kindSkipErr) Error() string {
-	return fmt.Sprintf("resource kind %q is configured to be skipped", e.Kind)
+func (e *skipErr) Error() string {
+	return fmt.Sprintf("resource %s %q is configured to be skipped", e.kind, e.name)
 }

slice/errors_test.go

@@ -3,6 +3,6 @@ package slice
 import "testing"
 
 func TestErrorsInterface(t *testing.T) {
-	var _ error = &strictModeErr{}
-	var _ error = &kindSkipErr{}
+	var _ error = &strictModeSkipErr{}
+	var _ error = &skipErr{}
 }

slice/execute.go

@@ -30,25 +30,22 @@ func (s *Split) processSingleFile(file []byte) error {
 			return nil
 		}
 
-		s.fileCount++
 		return nil
 	}
 
 	// Add an empty line at the end
 	file = append(file, []byte("\n\n")...)
 
 	// Send it for processing
-	name, kind, err := s.parseYAMLManifest(file, s.fileCount, s.template)
+	meta, err := s.parseYAMLManifest(file)
 	if err != nil {
 		switch err.(type) {
-		case *kindSkipErr:
+		case *skipErr:
 			s.log.Printf("Skipping file %d: %s", s.fileCount, err.Error())
-			s.fileCount++
 			return nil
 
-		case *strictModeErr:
+		case *strictModeSkipErr:
 			s.log.Printf("Skipping file %d: %s", s.fileCount, err.Error())
-			s.fileCount++
 			return nil
 
 		default:
@@ -58,41 +55,39 @@ func (s *Split) processSingleFile(file []byte) error {
 
 	existentData, position := []byte(nil), -1
 	for pos := 0; pos < len(s.filesFound); pos++ {
-		if s.filesFound[pos].name == name {
+		if s.filesFound[pos].filename == meta.filename {
 			existentData = s.filesFound[pos].data
 			position = pos
 			break
 		}
 	}
 
 	if position == -1 {
-		s.log.Printf("Got nonexistent file. Adding it to the list: %s", name)
+		s.log.Printf("Got nonexistent file. Adding it to the list: %s", meta.filename)
 		s.filesFound = append(s.filesFound, yamlFile{
-			name: name,
-			kind: kind,
-			data: file,
+			filename: meta.filename,
+			meta:     meta.meta,
+			data:     file,
 		})
 	} else {
-		s.log.Printf("Got existent file. Appending to original buffer: %s", name)
+		s.log.Printf("Got existent file. Appending to original buffer: %s", meta.filename)
 		existentData = append(existentData, []byte("---\n\n")...)
 		existentData = append(existentData, file...)
 		s.filesFound[position] = yamlFile{
-			name: name,
-			kind: kind,
-			data: existentData,
+			filename: meta.filename,
+			meta:     meta.meta,
+			data:     existentData,
 		}
 	}
 
-	s.fileCount++
 	return nil
 }
 
 func (s *Split) scan() error {
-	s.fileCount = 0
-
 	// Since we'll be iterating over files that potentially might end up being
 	// duplicated files, we need to store them somewhere to, later, save them
 	// to files
+	s.fileCount = 0
 	s.filesFound = make([]yamlFile, 0)
 
 	// We can totally create a single decoder then decode using that, however,
@@ -125,6 +120,7 @@ func (s *Split) scan() error {
 				if err := parseFile(); err != nil {
 					return err
 				}
+				s.fileCount++
 				break
 			}
 
@@ -138,6 +134,7 @@ func (s *Split) scan() error {
 			if err := parseFile(); err != nil {
 				return err
 			}
+			s.fileCount++
 			continue
 		}
 
@@ -164,7 +161,7 @@ func (s *Split) store() error {
 	for _, v := range s.filesFound {
 		s.fileCount++
 
-		fullpath := filepath.Join(s.opts.OutputDirectory, v.name)
+		fullpath := filepath.Join(s.opts.OutputDirectory, v.filename)
 		fileLength := len(v.data)
 
 		s.log.Printf("Handling file %q: %d bytes long.", fullpath, fileLength)
@@ -185,7 +182,7 @@ func (s *Split) store() error {
 
 		default:
 			// do nothing, handling below
-			if err := writeToFile(fullpath, v.data); err != nil {
+			if err := s.writeToFile(fullpath, v.data); err != nil {
 				return err
 			}
 
@@ -226,7 +223,7 @@ func (s *Split) Execute() error {
 	return s.store()
 }
 
-func writeToFile(path string, data []byte) error {
+func (s *Split) writeToFile(path string, data []byte) error {
 	// Since a single Go Template File Name might render different folder prefixes,
 	// we need to ensure they're all created.
 	if err := os.MkdirAll(filepath.Dir(path), folderChmod); err != nil {
@@ -235,6 +232,7 @@ func writeToFile(path string, data []byte) error {
 
 	// Open the file as read/write, create the file if it doesn't exist, and if
 	// it does, truncate it.
+	s.log.Printf("Opening file path %q", path)
 	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, defaultChmod)
 	if err != nil {
 		return fmt.Errorf("unable to create/open file %q: %w", path, err)