feat: add example sub-command

README.md

@@ -94,6 +94,13 @@ First, put the following TOML file in `~/.config/vin/vin.toml`.
 repo = "cli/cli"
 ```
 
+You can set this with the following command.
+
+```console
+mkdir -p ~/.config/vin
+vin example > ~/.config/vin/vin.toml
+```
+
 Yes, all you have to do is run the following command.
 
 ```console

app.go

@@ -14,25 +14,25 @@ import (
 // App represents an application.
 type App struct {
 	// Repo is the GitHub repository name in "owner/repo" format.
-	Repo string `toml:"repo"`
+	Repo string `toml:"repo,omitempty"`
 
 	// Tag is the tag on GitHub.
-	Tag string `toml:"tag"`
+	Tag string `toml:"tag,omitempty"`
 
 	// Keywords is a list of keywords for selecting suitable assets from multiple assets.
-	Keywords []string `toml:"keywords"`
+	Keywords []string `toml:"keywords,omitempty"`
 
 	// Name is the name of the executable file.
-	Name string `toml:"name"`
+	Name string `toml:"name,omitempty"`
 
 	// Hosts is a list of host names.
-	Hosts []string `toml:"hosts"`
+	Hosts []string `toml:"hosts,omitempty"`
 
 	// Priority is the priority of the application.
-	Priority int `toml:"priority"`
+	Priority int `toml:"priority,omitempty"`
 
 	// Command is the command to run after installation.
-	Command string `toml:"command"`
+	Command string `toml:"command,omitempty"`
 
 	release *github.RepositoryRelease
 }

cli/cli.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -12,6 +13,7 @@ import (
 	"github.com/AlecAivazis/survey/v2"
 	"github.com/fatih/color"
 	multierror "github.com/hashicorp/go-multierror"
+	"github.com/naoina/toml"
 	"github.com/skmatz/vin"
 	"github.com/vbauerster/mpb/v5"
 	"golang.org/x/sync/errgroup"
@@ -188,6 +190,21 @@ func (c *CLI) Clean() error {
 	return nil
 }
 
+// Example shows a config example.
+func (c *CLI) Example() error {
+	v := vin.Vin{
+		Apps: []vin.App{{
+			Repo: "cli/cli",
+		}},
+	}
+	var buf bytes.Buffer
+	if err := toml.NewEncoder(&buf).Encode(v); err != nil {
+		return err
+	}
+	fmt.Print(buf.String())
+	return nil
+}
+
 const tokenGenerateURL = "https://github.com/settings/tokens/new?description=Vin" //nolint:gosec
 
 // AskGitHubAccessToken prompts for the GitHub access token.

cmd/vin/cmd/cmd_example.go

@@ -0,0 +1,22 @@
+package cmd
+
+import (
+	"github.com/skmatz/vin/cli"
+	"github.com/spf13/cobra"
+)
+
+func runExample(cmd *cobra.Command, args []string) error {
+	c := cli.New()
+	return c.Example()
+}
+
+var exampleCmd = &cobra.Command{
+	Use:   "example",
+	Short: "Show a config example",
+	Long:  "Show a config example.",
+	RunE:  runExample,
+}
+
+func init() {
+	rootCmd.AddCommand(exampleCmd)
+}

go.mod

@@ -9,7 +9,10 @@ require (
 	github.com/google/go-github v17.0.0+incompatible
 	github.com/google/go-querystring v1.0.0 // indirect
 	github.com/hashicorp/go-multierror v1.0.0
+	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/mholt/archiver/v3 v3.5.0
+	github.com/naoina/go-stringutil v0.1.0 // indirect
+	github.com/naoina/toml v0.1.1
 	github.com/spf13/cobra v1.1.1
 	github.com/vbauerster/mpb/v5 v5.3.0
 	golang.org/x/oauth2 v0.0.0-20201109201403-9fd604954f58

go.sum

@@ -205,6 +205,8 @@ github.com/kr/pty v1.1.4 h1:5Myjjh3JY/NaAi4IsUbHADytDyl1VE1Y9PXDlL+P/VQ=
 github.com/kr/pty v1.1.4/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
+github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/magiconair/properties v1.8.1/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
@@ -233,6 +235,10 @@ github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
+github.com/naoina/go-stringutil v0.1.0 h1:rCUeRUHjBjGTSHl0VC00jUPLz8/F9dDzYI70Hzifhks=
+github.com/naoina/go-stringutil v0.1.0/go.mod h1:XJ2SJL9jCtBh+P9q5btrd/Ylo8XwT/h1USek5+NqSA0=
+github.com/naoina/toml v0.1.1 h1:PT/lllxVVN0gzzSqSlHEmP8MJB4MY2U7STGxiouV4X8=
+github.com/naoina/toml v0.1.1/go.mod h1:NBIhNtsFMo3G2szEBne+bO4gS192HuIYRqfvOWb4i1E=
 github.com/nwaples/rardecode v1.1.0 h1:vSxaY8vQhOcVr4mm5e8XllHWTiM4JF507A0Katqw7MQ=
 github.com/nwaples/rardecode v1.1.0/go.mod h1:5DzqNKiOdpKKBH87u8VlvAnPZMXcGRhxWkRpHbbfGS0=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=