feat(format): add format functionality

Refs: close #2

cmd/format.go

@@ -0,0 +1,124 @@
+/*
+Copyright (c) 2021 amplia-iiot
+
+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.
+*/
+package cmd
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/amplia-iiot/yutil/internal/io"
+	"github.com/amplia-iiot/yutil/pkg/format"
+	"github.com/spf13/cobra"
+)
+
+type FormatOptions struct {
+	outputFile string
+	inPlace    bool
+	suffix     string
+}
+
+var formatOptions FormatOptions
+
+// formatCmd represents the format command
+var formatCmd = &cobra.Command{
+	Use:   "format [FILE...]",
+	Short: "Format a yaml file",
+	Long: `Format a yaml file ordering its keys alphabetically and
+cleaning it.
+
+For example:
+
+yutil format file.yml
+yutil format file.yml -o file.formatted.yml
+cat file.yml | yutil format > file.formatted.yml
+echo "this is not a yaml" | yutil --no-input format file.yml > file.formatted.yml
+`,
+	Args: func(cmd *cobra.Command, args []string) error {
+		if inPlaceEnabled(cmd) {
+			if canAccessStdin() {
+				return errors.New("stdin not compatible with in place format")
+			}
+			if formatOptions.outputFile != "" {
+				return errors.New("output option not compatible with in place format")
+			}
+		} else {
+			if canAccessStdin() && len(args) != 0 {
+				return errors.New("only one yaml can be formatted to output, stdin is active")
+			} else if !canAccessStdin() && len(args) == 0 {
+				if stdinBlocked() {
+					return errors.New("requires one file to be formatted, stdin is blocked")
+				} else {
+					return errors.New("requires one file to be formatted")
+				}
+			} else if !canAccessStdin() && len(args) != 1 {
+				return errors.New("only one file can be formatted to output")
+			}
+		}
+		for _, file := range args {
+			if !io.Exists(file) {
+				return fmt.Errorf("file %s does not exist", file)
+			}
+		}
+		return nil
+	},
+	Run: func(cmd *cobra.Command, args []string) {
+		var err error
+		if inPlaceEnabled(cmd) {
+			if formatOptions.suffix == "" {
+				err = format.FormatFilesInPlace(args)
+			} else {
+				err = format.FormatFilesInPlaceB(args, formatOptions.suffix)
+			}
+		} else {
+			var formatted string
+			if canAccessStdin() {
+				formatted, err = format.FormatStdin()
+			} else {
+				formatted, err = format.FormatFile(args[0])
+			}
+			if err != nil {
+				panic(err)
+			}
+			if len(formatOptions.outputFile) > 0 {
+				err = io.WriteToFile(formatOptions.outputFile, formatted)
+			} else {
+				err = io.WriteToStdout(formatted)
+			}
+		}
+		if err != nil {
+			panic(err)
+		}
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(formatCmd)
+
+	formatCmd.Flags().StringVarP(&formatOptions.outputFile, "output", "o", "", "format yaml to output file instead of stdout (not compatible in place format)")
+	formatCmd.Flags().BoolVarP(&formatOptions.inPlace, "in-place", "i", false, "format yaml files in place (makes backup if suffix is supplied)")
+	formatCmd.Flags().StringVarP(&formatOptions.suffix, "suffix", "s", "", "format yaml files in place making a backup with the given suffix (-i is not necessary if suffix is passed)")
+}
+
+// Whether in place format is enabled
+func inPlaceEnabled(cmd *cobra.Command) bool {
+	return formatOptions.inPlace || cmd.Flags().Changed("suffix")
+}

cmd/root.go

@@ -150,3 +150,8 @@ func canAccessStdin() bool {
 	noInput, err := rootCmd.Flags().GetBool("no-input")
 	return err == nil && io.ReceivedStdin() && !noInput
 }
+
+func stdinBlocked() bool {
+	noInput, err := rootCmd.Flags().GetBool("no-input")
+	return err == nil && noInput
+}

internal/io/writer.go

@@ -23,6 +23,8 @@ package io
 
 import (
 	"bufio"
+	"fmt"
+	"io"
 	"os"
 )
 
@@ -48,3 +50,25 @@ func Write(file *os.File, content string) error {
 	writer.Flush()
 	return nil
 }
+
+func Copy(src, dst string) error {
+	srcStat, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	if !srcStat.Mode().IsRegular() {
+		return fmt.Errorf("%s is not a regular file", src)
+	}
+	srcFile, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer srcFile.Close()
+	destination, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+	defer destination.Close()
+	_, err = io.Copy(destination, srcFile)
+	return err
+}

pkg/format/content.go

@@ -0,0 +1,43 @@
+/*
+Copyright (c) 2021 amplia-iiot
+
+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.
+*/
+package format
+
+import (
+	"github.com/amplia-iiot/yutil/internal/io"
+	"github.com/amplia-iiot/yutil/internal/yaml"
+)
+
+func FormatContent(content string) (string, error) {
+	contentData, err := yaml.Parse(content)
+	if err != nil {
+		return "", err
+	}
+	return yaml.Compose(contentData)
+}
+
+func FormatStdin() (string, error) {
+	content, err := io.ReadStdin()
+	if err != nil {
+		return "", err
+	}
+	return FormatContent(content)
+}