Added splitstring cli

Author: rsdoiel

cmds/splitstring/splitstring.go

@@ -0,0 +1,168 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"strings"
+
+	// Caltech Library Packages
+	"github.com/caltechlibrary/cli"
+	"github.com/caltechlibrary/datatools"
+)
+
+var (
+	usage = `USAGE: %s [OPTIONS] [STRING_TO_SPLIT]`
+
+	description = `
+%s splits a string based on a delimiting string provided. The default
+delimiter is a space. You can specify a delimiting string via 
+the -d or --delimiter option.  %s will split the string provided
+as a command line argument but can read split string(s) recieved on
+stdin in with the -i or --input option. By default the split
+strings are render as a JSON array but with the option -nl or
+--newline you can render each split string one per line.
+`
+
+	examples = `
+EXAMPLES
+
+Splitting a string that is double pipe delimited rendering
+one sub string per line.
+
+    %s -nl -d '||' "one||two||three"
+
+This should yield
+
+    one
+	two
+	three
+
+Splitting a string that is double pipe delimited rendering JSON
+
+    %s -d '||' "one||two||three"
+
+This should yield
+
+   ["one","two","three"]
+
+`
+
+	// Standard Options
+	showHelp     bool
+	showLicense  bool
+	showVersion  bool
+	showExamples bool
+	inputFName   string
+	outputFName  string
+
+	// App Options
+	delimiter string
+	newLine   bool
+)
+
+func init() {
+	// Standard options
+	flag.BoolVar(&showHelp, "h", false, "display help")
+	flag.BoolVar(&showHelp, "help", false, "display help")
+	flag.BoolVar(&showLicense, "l", false, "display license")
+	flag.BoolVar(&showLicense, "license", false, "display license")
+	flag.BoolVar(&showVersion, "v", false, "display version")
+	flag.BoolVar(&showVersion, "version", false, "display version")
+	flag.BoolVar(&showExamples, "example", false, "display example(s)")
+	flag.StringVar(&inputFName, "i", "", "input filename")
+	flag.StringVar(&inputFName, "input", "", "input filename")
+	flag.StringVar(&outputFName, "o", "", "output filename")
+	flag.StringVar(&outputFName, "output", "", "output filename")
+
+	// Application specific options
+	flag.StringVar(&delimiter, "d", " ", "set the delimiting string value")
+	flag.StringVar(&delimiter, "delimiter", " ", "set the delimiting string value")
+	flag.BoolVar(&newLine, "nl", false, "output as one substring per line rather than JSON")
+	flag.BoolVar(&newLine, "newline", false, "output as one substring per line rather than JSON")
+}
+
+func main() {
+	appName := path.Base(os.Args[0])
+	flag.Parse()
+	args := flag.Args()
+
+	cfg := cli.New(appName, "", datatools.Version)
+	cfg.UsageText = fmt.Sprintf(usage, appName)
+	cfg.DescriptionText = fmt.Sprintf(description, appName)
+	cfg.OptionText = "OPTIONS"
+	cfg.ExampleText = fmt.Sprintf(examples, appName, appName)
+
+	if showHelp == true {
+		if len(args) > 0 {
+			fmt.Println(cfg.Help(args...))
+		} else {
+			fmt.Println(cfg.Usage())
+		}
+		os.Exit(0)
+	}
+
+	if showExamples == true {
+		if len(args) > 0 {
+			fmt.Println(cfg.Example(args...))
+		} else {
+			fmt.Println(cfg.ExampleText)
+		}
+		os.Exit(0)
+	}
+
+	if showLicense == true {
+		fmt.Println(cfg.License())
+		os.Exit(0)
+	}
+
+	if showVersion == true {
+		fmt.Println(cfg.Version())
+		os.Exit(0)
+	}
+
+	in, err := cli.Open(inputFName, os.Stdin)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s\n", err)
+		os.Exit(1)
+	}
+	defer cli.CloseFile(inputFName, in)
+
+	out, err := cli.Create(outputFName, os.Stdout)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "%s\n", err)
+		os.Exit(1)
+	}
+	defer cli.CloseFile(outputFName, out)
+
+	if inputFName != "" {
+		src, err := ioutil.ReadAll(in)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Can't read file, %s", err)
+			os.Exit(1)
+		}
+		args = strings.Split(string(src), "\n")
+	}
+
+	results := []string{}
+	for _, s := range args {
+		parts := strings.Split(s, delimiter)
+		for _, p := range parts {
+			results = append(results, p)
+		}
+	}
+
+	if newLine == true {
+		fmt.Fprintf(out, "%s\n", strings.Join(results, "\n"))
+	} else {
+		src, err := json.Marshal(results)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Can't marshal %+v", err)
+			os.Exit(1)
+		}
+		fmt.Fprintf(out, "%s\n", src)
+	}
+}