bring in khatru and eventstore.

eventstore/cmd/eventstore/helpers.go

@@ -0,0 +1,134 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/urfave/cli/v3"
+)
+
+const (
+	LINE_PROCESSING_ERROR = iota
+)
+
+func detect(dir string) (string, error) {
+	mayBeMMM := false
+	if n := strings.Index(dir, "/"); n > 0 {
+		mayBeMMM = true
+		dir = filepath.Dir(dir)
+	}
+
+	f, err := os.Stat(dir)
+	if err != nil {
+		return "", err
+	}
+	if !f.IsDir() {
+		f, err := os.Open(dir)
+		if err != nil {
+			return "", err
+		}
+		buf := make([]byte, 15)
+		f.Read(buf)
+		if string(buf) == "SQLite format 3" {
+			return "sqlite", nil
+		}
+
+		return "", fmt.Errorf("unknown db format")
+	}
+
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return "", err
+	}
+
+	if mayBeMMM {
+		for _, entry := range entries {
+			if entry.Name() == "mmmm" {
+				if entries, err := os.ReadDir(filepath.Join(dir, "mmmm")); err == nil {
+					for _, e := range entries {
+						if strings.HasSuffix(e.Name(), ".mdb") {
+							return "mmm", nil
+						}
+					}
+				}
+			}
+		}
+	}
+	for _, entry := range entries {
+		if strings.HasSuffix(entry.Name(), ".mdb") {
+			return "lmdb", nil
+		}
+		if strings.HasSuffix(entry.Name(), ".vlog") {
+			return "badger", nil
+		}
+	}
+
+	return "", fmt.Errorf("undetected")
+}
+
+func getStdin() string {
+	stat, _ := os.Stdin.Stat()
+	if (stat.Mode() & os.ModeCharDevice) == 0 {
+		read := bytes.NewBuffer(make([]byte, 0, 1000))
+		_, err := io.Copy(read, os.Stdin)
+		if err == nil {
+			return read.String()
+		}
+	}
+	return ""
+}
+
+func isPiped() bool {
+	stat, _ := os.Stdin.Stat()
+	return stat.Mode()&os.ModeCharDevice == 0
+}
+
+func getStdinLinesOrFirstArgument(c *cli.Command) chan string {
+	// try the first argument
+	target := c.Args().First()
+	if target != "" {
+		single := make(chan string, 1)
+		single <- target
+		close(single)
+		return single
+	}
+
+	// try the stdin
+	multi := make(chan string)
+	writeStdinLinesOrNothing(multi)
+	return multi
+}
+
+func getStdinLinesOrBlank() chan string {
+	multi := make(chan string)
+	if hasStdinLines := writeStdinLinesOrNothing(multi); !hasStdinLines {
+		single := make(chan string, 1)
+		single <- ""
+		close(single)
+		return single
+	} else {
+		return multi
+	}
+}
+
+func writeStdinLinesOrNothing(ch chan string) (hasStdinLines bool) {
+	if isPiped() {
+		// piped
+		go func() {
+			scanner := bufio.NewScanner(os.Stdin)
+			for scanner.Scan() {
+				ch <- strings.TrimSpace(scanner.Text())
+			}
+			close(ch)
+		}()
+		return true
+	} else {
+		// not piped
+		return false
+	}
+}