Create new submodule history

Dedupe unit test passes.

cmd/rqlite/history/file.go

@@ -0,0 +1,59 @@
+package history
+
+import (
+	"io"
+	"os"
+)
+
+type HiddenWriter struct {
+	path string
+	file *os.File
+}
+
+func NewHiddenWriter(path string) *HiddenWriter {
+	return &HiddenWriter{
+		path: "." + path,
+	}
+}
+
+func (h *HiddenWriter) Open() error {
+	var err error
+	h.file, err = os.OpenFile(h.path, os.O_CREATE|os.O_WRONLY, 0644)
+	return err
+}
+
+func (h *HiddenWriter) Write(p []byte) (n int, err error) {
+	return h.file.Write(p)
+}
+
+func (h *HiddenWriter) Close() error {
+	return h.file.Close()
+}
+
+func Reader() io.ReadCloser {
+	file := os.Getenv("RQLITE_HISTFILE")
+	if file == "" {
+		file = "rqlite_history"
+	}
+
+	// Call OS-specific function actually
+	f, err := os.Open(file)
+	if err != nil {
+		return nil
+	}
+	return f
+}
+
+func Writer() io.WriteCloser {
+	file := os.Getenv("RQLITE_HISTFILE")
+	if file == "" {
+		file = "rqlite_history"
+	}
+
+	// Call OS-specific function actually
+	f, err := os.OpenFile(file, os.O_RDWR|os.O_CREATE, 0755)
+	if err != nil {
+		return nil
+	}
+	return f
+}

cmd/rqlite/history/history.go

@@ -0,0 +1,88 @@
+package history
+
+import (
+	"bufio"
+	"io"
+	"os"
+	"strconv"
+)
+
+const MaxHistSize = 100
+
+func Dedupe(s []string) []string {
+	if s == nil {
+		return nil
+	}
+
+	o := make([]string, 0, len(s))
+	for si := 0; si < len(s); si++ {
+		if si == 0 || s[si] != o[len(o)-1] {
+			o = append(o, s[si])
+		}
+	}
+	return o
+}
+
+func FileSize() int {
+	maxSize := MaxHistSize
+	maxSizeStr := os.Getenv("RQLITE_HISTFILESIZE")
+	if maxSizeStr != "" {
+		sz, err := strconv.Atoi(maxSizeStr)
+		if err == nil && maxSize > 0 {
+			maxSize = sz
+		}
+	}
+	return maxSize
+}
+
+func Read(r io.Reader) ([]string, error) {
+	if r == nil {
+		return nil, nil
+	}
+
+	var cmds []string
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		cmds = append(cmds, scanner.Text())
+	}
+
+	return cmds, scanner.Err()
+}
+
+func Write(j []string, maxSz int, w io.Writer) error {
+	if len(j) == 0 {
+		return nil
+	}
+
+	if w == nil {
+		return nil
+	}
+
+	// Cut start off slice is bigger, but before or after dupes?
+	if len(j) > maxSz {
+		j = j[len(j)-maxSz:]
+	}
+
+	i := 0
+	var k []string
+	for {
+		k = append(k, j[i])
+
+		for {
+			if i < len(j)-1 && j[i] == j[i+1] {
+				i++
+				continue
+			} else if i == len(j) {
+
+			}
+		}
+	}
+
+	for i := 0; i < len(k)-1; i++ {
+		if _, err := w.Write([]byte(k[i] + "\n")); err != nil {
+			return err
+		}
+	}
+	_, err := w.Write([]byte(k[len(k)-1]))
+	return err
+}

cmd/rqlite/history/history_test.go

@@ -0,0 +1,57 @@
+package history
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_Dedupe(t *testing.T) {
+	for i, tt := range []struct {
+		orig []string
+		exp  []string
+	}{
+		{
+			orig: nil,
+			exp:  nil,
+		},
+		{
+			orig: []string{"foo"},
+			exp:  []string{"foo"},
+		},
+		{
+			orig: []string{"foo", "bar"},
+			exp:  []string{"foo", "bar"},
+		},
+		{
+			orig: []string{"foo", "bar", "foo"},
+			exp:  []string{"foo", "bar", "foo"},
+		},
+		{
+			orig: []string{"foo", "foo", "foo"},
+			exp:  []string{"foo"},
+		},
+		{
+			orig: []string{"foo", "bar", "foo", "foo"},
+			exp:  []string{"foo", "bar", "foo"},
+		},
+		{
+			orig: []string{"foo", "foo", "bar", "foo", "foo"},
+			exp:  []string{"foo", "bar", "foo"},
+		},
+		{
+			orig: []string{"foo", "foo", "bar", "foo", "foo", "qux"},
+			exp:  []string{"foo", "bar", "foo", "qux"},
+		},
+		{
+			orig: []string{"foo", "foo", "bar", "bar", "foo", "foo", "qux"},
+			exp:  []string{"foo", "bar", "foo", "qux"},
+		},
+	} {
+		got := Dedupe(tt.orig)
+		if !reflect.DeepEqual(tt.exp, got) {
+			t.Fatalf("test %d failed, exp %s, got %s", i, tt.exp, got)
+		}
+
+	}
+	return
+}