Merge pull request #1070 from rhatdan/format

Add --format option to skopeo inspect

cmd/skopeo/inspect.go

@@ -4,8 +4,12 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"os"
 	"strings"
+	"text/tabwriter"
+	"text/template"
 
+	"github.com/containers/common/pkg/report"
 	"github.com/containers/common/pkg/retry"
 	"github.com/containers/image/v5/docker"
 	"github.com/containers/image/v5/image"
@@ -23,6 +27,7 @@ type inspectOptions struct {
 	global    *globalOptions
 	image     *imageOptions
 	retryOpts *retry.RetryOptions
+	format    string
 	raw       bool // Output the raw manifest instead of parsing information about the image
 	config    bool // Output the raw config blob instead of parsing information about the image
 }
@@ -46,12 +51,15 @@ Supported transports:
 See skopeo(1) section "IMAGE NAMES" for the expected format
 `, strings.Join(transports.ListNames(), ", ")),
 		RunE: commandAction(opts.run),
-		Example: `skopeo inspect docker://docker.io/fedora`,
+		Example: `skopeo inspect docker://registry.fedoraproject.org/fedora
+  skopeo inspect --config docker://docker.io/alpine
+  skopeo inspect  --format "Name: {{.Name}} Digest: {{.Digest}}" docker://registry.access.redhat.com/ubi8`,
 	}
 	adjustUsage(cmd)
 	flags := cmd.Flags()
 	flags.BoolVar(&opts.raw, "raw", false, "output raw manifest or configuration")
 	flags.BoolVar(&opts.config, "config", false, "output configuration")
+	flags.StringVarP(&opts.format, "format", "f", "", "Format the output to a Go template")
 	flags.AddFlagSet(&sharedFlags)
 	flags.AddFlagSet(&imageFlags)
 	flags.AddFlagSet(&retryFlags)
@@ -63,6 +71,7 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 		rawManifest []byte
 		src         types.ImageSource
 		imgInspect  *types.ImageInspectInfo
+		data        []interface{}
 	)
 	ctx, cancel := opts.global.commandTimeoutContext()
 	defer cancel()
@@ -70,6 +79,9 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 	if len(args) != 1 {
 		return errors.New("Exactly one argument expected")
 	}
+	if opts.raw && opts.format != "" {
+		return errors.New("raw output does not support format option")
+	}
 	imageName := args[0]
 
 	if err := reexecIfNecessaryForImages(imageName); err != nil {
@@ -106,12 +118,13 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 		if err != nil {
 			return fmt.Errorf("Error writing manifest to standard output: %v", err)
 		}
+
 		return nil
 	}
 
 	img, err := image.FromUnparsedImage(ctx, sys, image.UnparsedInstance(src, nil))
 	if err != nil {
-		return fmt.Errorf("Error parsing manifest for image: %v", err)
+		return errors.Wrapf(err, "Error parsing manifest for image")
 	}
 
 	if opts.config && opts.raw {
@@ -124,7 +137,7 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 		}
 		_, err = stdout.Write(configBlob)
 		if err != nil {
-			return fmt.Errorf("Error writing configuration blob to standard output: %v", err)
+			return errors.Wrapf(err, "Error writing configuration blob to standard output")
 		}
 		return nil
 	} else if opts.config {
@@ -135,9 +148,19 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 		}, opts.retryOpts); err != nil {
 			return errors.Wrapf(err, "Error reading OCI-formatted configuration data")
 		}
-		err = json.NewEncoder(stdout).Encode(config)
+		if report.IsJSON(opts.format) || opts.format == "" {
+			var out []byte
+			out, err = json.MarshalIndent(config, "", "    ")
+			if err == nil {
+				fmt.Fprintf(stdout, "%s\n", string(out))
+			}
+		} else {
+			row := "{{range . }}" + report.NormalizeFormat(opts.format) + "{{end}}"
+			data = append(data, config)
+			err = printTmpl(row, data)
+		}
 		if err != nil {
-			return fmt.Errorf("Error writing OCI-formatted configuration data to standard output: %v", err)
+			return errors.Wrapf(err, "Error writing OCI-formatted configuration data to standard output")
 		}
 		return nil
 	}
@@ -164,7 +187,7 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 	}
 	outputData.Digest, err = manifest.Digest(rawManifest)
 	if err != nil {
-		return fmt.Errorf("Error computing manifest digest: %v", err)
+		return errors.Wrapf(err, "Error computing manifest digest")
 	}
 	if dockerRef := img.Reference().DockerReference(); dockerRef != nil {
 		outputData.Name = dockerRef.Name()
@@ -182,15 +205,35 @@ func (opts *inspectOptions) run(args []string, stdout io.Writer) (retErr error)
 			// In addition, AWS ECR rejects it with 403 (Forbidden) if the "ecr:ListImages"
 			// action is not allowed.
 			if !strings.Contains(err.Error(), "401") && !strings.Contains(err.Error(), "403") {
-				return fmt.Errorf("Error determining repository tags: %v", err)
+				return errors.Wrapf(err, "Error determining repository tags")
 			}
 			logrus.Warnf("Registry disallows tag list retrieval; skipping")
 		}
 	}
+	if report.IsJSON(opts.format) || opts.format == "" {
 		out, err := json.MarshalIndent(outputData, "", "    ")
+		if err == nil {
+			fmt.Fprintf(stdout, "%s\n", string(out))
+		}
+		return err
+	}
+	row := "{{range . }}" + report.NormalizeFormat(opts.format) + "{{end}}"
+	data = append(data, outputData)
+	return printTmpl(row, data)
+}
+
+func inspectNormalize(row string) string {
+	r := strings.NewReplacer(
+		".ImageID", ".Image",
+	)
+	return r.Replace(row)
+}
+
+func printTmpl(row string, data []interface{}) error {
+	t, err := template.New("skopeo inspect").Parse(row)
 	if err != nil {
 		return err
 	}
-	fmt.Fprintf(stdout, "%s\n", string(out))
+	w := tabwriter.NewWriter(os.Stdout, 8, 2, 2, ' ', 0)
-	return nil
+	return t.Execute(w, data)
 }

completions/bash/skopeo

@@ -75,6 +75,7 @@ _skopeo_inspect() {
      --authfile
      --creds
      --cert-dir
+     --format
      --retry-times
      --registry-token
      "

docs/skopeo-inspect.1.md

@@ -4,38 +4,58 @@
 skopeo\-inspect - Return low-level information about _image-name_ in a registry.
 
 ## SYNOPSIS
-**skopeo inspect** [**--raw**] [**--config**] _image-name_
+**skopeo inspect** [*options*] _image-name_
+
+## DESCRIPTION
 
 Return low-level information about _image-name_ in a registry
 
-  **--raw** output raw manifest, default is to format in JSON
+_image-name_ name of image to retrieve information about
 
-  _image-name_ name of image to retrieve information about
+## OPTIONS
 
-  **--config** output configuration in OCI format, default is to format in JSON
+**--authfile** _path_
 
-  _image-name_ name of image to retrieve configuration for
+Path of the authentication file. Default is ${XDG\_RUNTIME\_DIR}/containers/auth.json, which is set using `skopeo login`.
+If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using `docker login`.
 
-  **--config** **--raw** output configuration in raw format
+**--cert-dir** _path_
 
-  _image-name_ name of image to retrieve configuration for
+Use certificates at _path_ (\*.crt, \*.cert, \*.key) to connect to the registry.
 
-  **--authfile** _path_
+**--config**
 
-  Path of the authentication file. Default is ${XDG\_RUNTIME\_DIR}/containers/auth.json, which is set using `skopeo login`.
+Output configuration in OCI format, default is to format in JSON format.
-  If the authorization state is not found there, $HOME/.docker/config.json is checked, which is set using `docker login`.
 
-  **--creds** _username[:password]_ for accessing the registry.
+**--creds** _username[:password]_
 
-  **--cert-dir** _path_ Use certificates at _path_ (\*.crt, \*.cert, \*.key) to connect to the registry.
+Username and password for accessing the registry.
 
-  **--retry-times**  the number of times to retry, retry wait time will be exponentially increased based on the number of failed attempts.
+**--format**, **-f**=*format*
 
-  **--tls-verify** _bool-value_ Require HTTPS and verify certificates when talking to container registries (defaults to true).
+Format the output using the given Go template.
+The keys of the returned JSON can be used as the values for the --format flag (see examples below).
 
-  **--no-creds** _bool-value_ Access the registry anonymously.
+**--no-creds**
 
-  **--registry-token** _Bearer token_ for accessing the registry.
+Access the registry anonymously.
+
+**--raw**
+
+Output raw manifest or config data depending on --config option.
+The --format option is not supported with --raw option.
+
+**--registry-token** _Bearer token_
+
+Registry token for accessing the registry.
+
+**--retry-times**
+
+The number of times to retry; retry wait time will be exponentially increased based on the number of failed attempts.
+
+**--tls-verify**
+
+Require HTTPS and verify certificates when talking to container registries (defaults to true).
 
 ## EXAMPLES
 
@@ -66,10 +86,19 @@ $ skopeo inspect docker://docker.io/fedora
 }
 ```
 
+```
+$ /bin/skopeo inspect --config docker://registry.fedoraproject.org/fedora --format "{{ .Architecture }}"
+amd64
+```
+
+```
+$ /bin/skopeo inspect --format '{{ .Env }}' docker://registry.access.redhat.com/ubi8
+[PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin container=oci]
+```
+
 # SEE ALSO
 skopeo(1), skopeo-login(1), docker-login(1), containers-auth.json(5)
 
 ## AUTHORS
 
 Antonio Murdaca <runcom@redhat.com>, Miloslav Trmac <mitr@redhat.com>, Jhon Honce <jhonce@redhat.com>
-

vendor/github.com/containers/common/pkg/report/camelcase/LICENSE.md

@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Fatih Arslan
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/containers/common/pkg/report/camelcase/README.md

@@ -0,0 +1,58 @@
+# CamelCase [![GoDoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](http://godoc.org/github.com/fatih/camelcase) [![Build Status](http://img.shields.io/travis/fatih/camelcase.svg?style=flat-square)](https://travis-ci.org/fatih/camelcase)
+
+CamelCase is a Golang (Go) package to split the words of a camelcase type
+string into a slice of words. It can be used to convert a camelcase word (lower
+or upper case) into any type of word.
+
+## Splitting rules:
+
+1. If string is not valid UTF-8, return it without splitting as
+   single item array.
+2. Assign all unicode characters into one of 4 sets: lower case
+   letters, upper case letters, numbers, and all other characters.
+3. Iterate through characters of string, introducing splits
+   between adjacent characters that belong to different sets.
+4. Iterate through array of split strings, and if a given string
+   is upper case:
+   * if subsequent string is lower case:
+     * move last character of upper case string to beginning of
+       lower case string
+
+## Install
+
+```bash
+go get github.com/fatih/camelcase
+```
+
+## Usage and examples
+
+```go
+splitted := camelcase.Split("GolangPackage")
+
+fmt.Println(splitted[0], splitted[1]) // prints: "Golang", "Package"
+```
+
+Both lower camel case and upper camel case are supported. For more info please
+check: [http://en.wikipedia.org/wiki/CamelCase](http://en.wikipedia.org/wiki/CamelCase)
+
+Below are some example cases:
+
+```
+"" =>                     []
+"lowercase" =>            ["lowercase"]
+"Class" =>                ["Class"]
+"MyClass" =>              ["My", "Class"]
+"MyC" =>                  ["My", "C"]
+"HTML" =>                 ["HTML"]
+"PDFLoader" =>            ["PDF", "Loader"]
+"AString" =>              ["A", "String"]
+"SimpleXMLParser" =>      ["Simple", "XML", "Parser"]
+"vimRPCPlugin" =>         ["vim", "RPC", "Plugin"]
+"GL11Version" =>          ["GL", "11", "Version"]
+"99Bottles" =>            ["99", "Bottles"]
+"May5" =>                 ["May", "5"]
+"BFG9000" =>              ["BFG", "9000"]
+"BöseÜberraschung" =>     ["Böse", "Überraschung"]
+"Two  spaces" =>          ["Two", "  ", "spaces"]
+"BadUTF8\xe2\xe2\xa1" =>  ["BadUTF8\xe2\xe2\xa1"]
+```

vendor/github.com/containers/common/pkg/report/camelcase/camelcase.go

@@ -0,0 +1,91 @@
+// Package camelcase is a micro package to split the words of a camelcase type
+// string into a slice of words.
+package camelcase
+
+import (
+	"unicode"
+	"unicode/utf8"
+)
+
+// Split splits the camelcase word and returns a list of words. It also
+// supports digits. Both lower camel case and upper camel case are supported.
+// For more info please check: http://en.wikipedia.org/wiki/CamelCase
+//
+// Examples
+//
+//   "" =>                     [""]
+//   "lowercase" =>            ["lowercase"]
+//   "Class" =>                ["Class"]
+//   "MyClass" =>              ["My", "Class"]
+//   "MyC" =>                  ["My", "C"]
+//   "HTML" =>                 ["HTML"]
+//   "PDFLoader" =>            ["PDF", "Loader"]
+//   "AString" =>              ["A", "String"]
+//   "SimpleXMLParser" =>      ["Simple", "XML", "Parser"]
+//   "vimRPCPlugin" =>         ["vim", "RPC", "Plugin"]
+//   "GL11Version" =>          ["GL", "11", "Version"]
+//   "99Bottles" =>            ["99", "Bottles"]
+//   "May5" =>                 ["May", "5"]
+//   "BFG9000" =>              ["BFG", "9000"]
+//   "BöseÜberraschung" =>     ["Böse", "Überraschung"]
+//   "Two  spaces" =>          ["Two", "  ", "spaces"]
+//   "BadUTF8\xe2\xe2\xa1" =>  ["BadUTF8\xe2\xe2\xa1"]
+//
+// Splitting rules
+//
+//  1) If string is not valid UTF-8, return it without splitting as
+//     single item array.
+//  2) Assign all unicode characters into one of 4 sets: lower case
+//     letters, upper case letters, numbers, and all other characters.
+//  3) Iterate through characters of string, introducing splits
+//     between adjacent characters that belong to different sets.
+//  4) Iterate through array of split strings, and if a given string
+//     is upper case:
+//       if subsequent string is lower case:
+//         move last character of upper case string to beginning of
+//         lower case string
+func Split(src string) (entries []string) {
+	// don't split invalid utf8
+	if !utf8.ValidString(src) {
+		return []string{src}
+	}
+	entries = []string{}
+	var runes [][]rune
+	lastClass := 0
+	class := 0
+	// split into fields based on class of unicode character
+	for _, r := range src {
+		switch {
+		case unicode.IsLower(r):
+			class = 1
+		case unicode.IsUpper(r):
+			class = 2
+		case unicode.IsDigit(r):
+			class = 3
+		default:
+			class = 4
+		}
+		if class == lastClass {
+			runes[len(runes)-1] = append(runes[len(runes)-1], r)
+		} else {
+			runes = append(runes, []rune{r})
+		}
+		lastClass = class
+	}
+	// handle upper case -> lower case sequences, e.g.
+	// "PDFL", "oader" -> "PDF", "Loader"
+	for i := 0; i < len(runes)-1; i++ {
+		if unicode.IsUpper(runes[i][0]) && unicode.IsLower(runes[i+1][0]) {
+			runes[i+1] = append([]rune{runes[i][len(runes[i])-1]}, runes[i+1]...)
+			runes[i] = runes[i][:len(runes[i])-1]
+		}
+	}
+	// construct []string from results
+	for _, s := range runes {
+		if len(s) > 0 {
+			entries = append(entries, string(s))
+		}
+	}
+
+	return entries
+}

vendor/github.com/containers/common/pkg/report/doc.go

@@ -0,0 +1,46 @@
+/*
+Package report provides helper structs/methods/funcs for formatting output
+
+To format output for an array of structs:
+
+	w := report.NewWriterDefault(os.Stdout)
+	defer w.Flush()
+
+	headers := report.Headers(struct {
+		ID string
+	}{}, nil)
+	t, _ := report.NewTemplate("command name").Parse("{{range .}}{{.ID}}{{end}}")
+	t.Execute(t, headers)
+	t.Execute(t, map[string]string{
+		"ID":"fa85da03b40141899f3af3de6d27852b",
+	})
+	// t.IsTable() == false
+
+or
+
+	w := report.NewWriterDefault(os.Stdout)
+	defer w.Flush()
+
+	headers := report.Headers(struct {
+		CID string
+	}{}, map[string]string{
+		"CID":"ID"})
+	t, _ := report.NewTemplate("command name").Parse("table {{.CID}}")
+	t.Execute(t, headers)
+	t.Execute(t,map[string]string{
+		"CID":"fa85da03b40141899f3af3de6d27852b",
+	})
+	// t.IsTable() == true
+
+Helpers:
+
+	if report.IsJSON(cmd.Flag("format").Value.String()) {
+		... process JSON and output
+	}
+
+and
+
+
+Note: Your code should not ignore errors
+*/
+package report

vendor/github.com/containers/common/pkg/report/template.go

@@ -0,0 +1,115 @@
+package report
+
+import (
+	"reflect"
+	"strings"
+	"text/template"
+
+	"github.com/containers/common/pkg/report/camelcase"
+)
+
+// Template embeds template.Template to add functionality to methods
+type Template struct {
+	*template.Template
+	isTable bool
+}
+
+// FuncMap is aliased from template.FuncMap
+type FuncMap template.FuncMap
+
+// tableReplacer will remove 'table ' prefix and clean up tabs
+var tableReplacer = strings.NewReplacer(
+	"table ", "",
+	`\t`, "\t",
+	`\n`, "\n",
+	" ", "\t",
+)
+
+// escapedReplacer will clean up escaped characters from CLI
+var escapedReplacer = strings.NewReplacer(
+	`\t`, "\t",
+	`\n`, "\n",
+)
+
+// NormalizeFormat reads given go template format provided by CLI and munges it into what we need
+func NormalizeFormat(format string) string {
+	var f string
+	// two replacers used so we only remove the prefix keyword `table`
+	if strings.HasPrefix(format, "table ") {
+		f = tableReplacer.Replace(format)
+	} else {
+		f = escapedReplacer.Replace(format)
+	}
+
+	if !strings.HasSuffix(f, "\n") {
+		f += "\n"
+	}
+	return f
+}
+
+// Headers queries the interface for field names.
+// Array of map is returned to support range templates
+// Note: unexported fields can be supported by adding field to overrides
+// Note: It is left to the developer to write out said headers
+//       Podman commands use the general rules of:
+//       1) unchanged --format includes headers
+//       2) --format '{{.ID}"        # no headers
+//       3) --format 'table {{.ID}}' # includes headers
+func Headers(object interface{}, overrides map[string]string) []map[string]string {
+	value := reflect.ValueOf(object)
+	if value.Kind() == reflect.Ptr {
+		value = value.Elem()
+	}
+
+	// Column header will be field name upper-cased.
+	headers := make(map[string]string, value.NumField())
+	for i := 0; i < value.Type().NumField(); i++ {
+		field := value.Type().Field(i)
+		// Recurse to find field names from promoted structs
+		if field.Type.Kind() == reflect.Struct && field.Anonymous {
+			h := Headers(reflect.New(field.Type).Interface(), nil)
+			for k, v := range h[0] {
+				headers[k] = v
+			}
+			continue
+		}
+		name := strings.Join(camelcase.Split(field.Name), " ")
+		headers[field.Name] = strings.ToUpper(name)
+	}
+
+	if len(overrides) > 0 {
+		// Override column header as provided
+		for k, v := range overrides {
+			headers[k] = strings.ToUpper(v)
+		}
+	}
+	return []map[string]string{headers}
+}
+
+// NewTemplate creates a new template object
+func NewTemplate(name string) *Template {
+	return &Template{template.New(name), false}
+}
+
+// Parse parses text as a template body for t
+func (t *Template) Parse(text string) (*Template, error) {
+	if strings.HasPrefix(text, "table ") {
+		t.isTable = true
+		text = "{{range .}}" + NormalizeFormat(text) + "{{end}}"
+	} else {
+		text = NormalizeFormat(text)
+	}
+
+	tt, err := t.Template.Parse(text)
+	return &Template{tt, t.isTable}, err
+}
+
+// Funcs adds the elements of the argument map to the template's function map
+func (t *Template) Funcs(funcMap FuncMap) *Template {
+	return &Template{t.Template.Funcs(template.FuncMap(funcMap)), t.isTable}
+}
+
+// IsTable returns true if format string defines a "table"
+func (t *Template) IsTable() bool {
+	return t.isTable
+}

vendor/github.com/containers/common/pkg/report/validate.go

@@ -0,0 +1,13 @@
+package report
+
+import "regexp"
+
+var jsonRegex = regexp.MustCompile(`^\s*(json|{{\s*json\s*(\.)?\s*}})\s*$`)
+
+// JSONFormat test CLI --format string to be a JSON request
+// if report.IsJSON(cmd.Flag("format").Value.String()) {
+//   ... process JSON and output
+// }
+func IsJSON(s string) bool {
+	return jsonRegex.MatchString(s)
+}

vendor/github.com/containers/common/pkg/report/writer.go

@@ -0,0 +1,27 @@
+package report
+
+import (
+	"io"
+	"text/tabwriter"
+)
+
+// Writer aliases tabwriter.Writer to provide Podman defaults
+type Writer struct {
+	*tabwriter.Writer
+}
+
+// NewWriter initializes a new report.Writer with given values
+func NewWriter(output io.Writer, minwidth, tabwidth, padding int, padchar byte, flags uint) (*Writer, error) {
+	t := tabwriter.NewWriter(output, minwidth, tabwidth, padding, padchar, flags)
+	return &Writer{t}, nil
+}
+
+// NewWriterDefault initializes a new report.Writer with Podman defaults
+func NewWriterDefault(output io.Writer) (*Writer, error) {
+	return NewWriter(output, 12, 2, 2, ' ', 0)
+}
+
+// Flush any output left in buffers
+func (w *Writer) Flush() error {
+	return w.Writer.Flush()
+}

vendor/modules.txt

@@ -38,6 +38,8 @@ github.com/containerd/containerd/errdefs
 github.com/containers/common/pkg/auth
 github.com/containers/common/pkg/capabilities
 github.com/containers/common/pkg/completion
+github.com/containers/common/pkg/report
+github.com/containers/common/pkg/report/camelcase
 github.com/containers/common/pkg/retry
 # github.com/containers/image/v5 v5.8.0
 github.com/containers/image/v5/copy