Refactor API

ftl

@@ -1,9 +1,11 @@
 #!/usr/bin/env sh
 set -x -e -u
 
-ssh $1 mkdir -p /root/go/src/github.com/ftlops/ftl
+ssh $1 rm -rf /root/go/src/github.com/ftlops/ftl/
+ssh $1 mkdir -p /root/go/src/github.com/ftlops/ftl/{log,ops}
 scp *.go $1:/root/go/src/github.com/ftlops/ftl/
-
+scp log/*.go $1:/root/go/src/github.com/ftlops/ftl/log
+scp ops/*.go $1:/root/go/src/github.com/ftlops/ftl/ops
 
 date=$(date +%s)
 dst=/var/log/ftl/$date/plans

ftl.go

@@ -1,7 +1,38 @@
 package ftl
 
-var DefaultOps = Ops{&LogLog{}}
+import (
+	"fmt"
+
+	"github.com/ftlops/ftl/log"
+	"github.com/ftlops/ftl/ops"
+)
+
+func init() {
+	ops.Logger = &log.DefaultLogger
+}
+
+type State int
+
+const (
+	StateUnchanged State = iota
+	StateChanged
+)
+
+func (s State) String() string {
+	switch s {
+	case StateUnchanged:
+		return "unchanged"
+	case StateChanged:
+		return "changed"
+	default:
+		return fmt.Sprintf("unknown (%d)", s)
+	}
+}
+
+type StepFunc func() State
 
 func Step(name string, f StepFunc) {
-	DefaultOps.Step(name, f)
+	log.BeginStep(name)
+	state := f()
+	log.EndStep(state.String())
 }

log/log.go

@@ -0,0 +1,92 @@
+package log
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"runtime/debug"
+	"strings"
+)
+
+var DefaultLogger = Logger{}
+
+func BeginStep(name string)  { DefaultLogger.BeginStep(name) }
+func EndStep(result string)  { DefaultLogger.EndStep(result) }
+func Fatal(v ...interface{}) { DefaultLogger.Fatal(v...) }
+func Error(v ...interface{}) { DefaultLogger.Error(v...) }
+func Info(v ...interface{})  { DefaultLogger.Info(v...) }
+func Debug(v ...interface{}) { DefaultLogger.Debug(v...) }
+func Trace(v ...interface{}) { DefaultLogger.Trace(v...) }
+
+type Logger struct {
+	stack   []string
+	lastFul string
+}
+
+func (l *Logger) BeginStep(name string) {
+	l.stack = append(l.stack, name)
+
+	l.printf("(((", []interface{}{})
+}
+
+func (l *Logger) EndStep(result string) {
+	l.printf(")))", []interface{}{"->", result})
+	l.stack = l.stack[:len(l.stack)-1]
+}
+
+func (l *Logger) Fatal(v ...interface{}) {
+	l.printf("FTL", v)
+	debug.PrintStack()
+	os.Exit(1)
+}
+
+func (l *Logger) Error(v ...interface{}) {
+	l.printf("ERR", v)
+}
+
+func (l *Logger) Info(v ...interface{}) {
+	l.printf("INF", v)
+}
+
+func (l *Logger) Debug(v ...interface{}) {
+	l.printf("DBG", v)
+}
+
+func (l *Logger) Trace(v ...interface{}) {
+	l.printf("TRC", v)
+}
+
+func (l *Logger) printf(lvl string, v []interface{}) {
+	full := l.fmtStack()
+	if l.lastFul != full {
+		log.Println(l.fmt(lvl, full, v)...)
+		l.lastFul = full
+	} else {
+		shortStack := "["
+		prefix := "... > "
+		basename := l.stack[len(l.stack)-1]
+		padLeft := len(full) - len(basename) - len(prefix) - 2
+		for i := 0; i < padLeft; i++ {
+			shortStack += " "
+		}
+		if padLeft > 0 {
+			shortStack += prefix
+		}
+		shortStack += basename + "]"
+		log.Println(l.fmt(lvl, shortStack, v)...)
+	}
+}
+
+func (l *Logger) fmt(lvl, stack string, v []interface{}) []interface{} {
+	var vs []interface{}
+	vs = append(vs, lvl)
+	vs = append(vs, stack)
+	for _, x := range v {
+		vs = append(vs, x)
+	}
+	return vs
+}
+
+func (l *Logger) fmtStack() string {
+	return fmt.Sprintf("[%s]", strings.Join(l.stack, " > "))
+}