From b91c1ebf6e70da7c6aa57c123095a9322f9a164b Mon Sep 17 00:00:00 2001
From: Nick Dumas <nobodys@business.com>
Date: Mon, 1 May 2023 16:38:27 -0400
Subject: [PATCH] Implement a walkFunc that feeds filenames into a channel

now i can lazily process them, fan them out, whatever
---
 cmd/fsm_demo/main.go | 42 ++++++++++++++++++++++++++++++++++++------
 fsm/nodes.go         |  6 +++++-
 2 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/cmd/fsm_demo/main.go b/cmd/fsm_demo/main.go
index 552e422..21e7e23 100644
--- a/cmd/fsm_demo/main.go
+++ b/cmd/fsm_demo/main.go
@@ -3,6 +3,9 @@ package main
 import (
 	"context"
 	"flag"
+	"io/fs"
+	"os"
+	"strings"
 
 	"go.uber.org/zap"
 
@@ -24,12 +27,39 @@ func main() {
 
 	flag.Parse()
 
-	m := fsm.NewStateMachine(&fsm.NoteFound)
-	note := "bleep"
-	ctx := context.WithValue(context.Background(), "note", note)
-	_, err := m.Transition(ctx, "CopyPost")
-	if err != nil {
-		l.Fatal("could not transition from NoteFound to CopyPost", zap.Error(err))
+	fileNames := make(chan string)
+
+	walkFunc := func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if d.IsDir() {
+			return nil
+		}
+		fileNames <- path
+
+		return nil
+	}
+
+	go func() {
+		for fn := range fileNames {
+			if !strings.HasSuffix(fn, ".md") {
+				continue
+			}
+			m := fsm.NewStateMachine(&fsm.NoteFound)
+			ctx := context.WithValue(context.Background(), "note", fn)
+			_, err := m.Transition(ctx, "CopyPost")
+			if err != nil {
+				l.Fatal("could not transition from NoteFound to CopyPost", zap.Error(err))
+			}
+		}
+	}()
 
+	root := os.DirFS(source)
+	err := fs.WalkDir(root, ".", walkFunc)
+	if err != nil {
+		l.Fatal("error walking for files", zap.Error(err))
 	}
+
 }
diff --git a/fsm/nodes.go b/fsm/nodes.go
index 27e425d..4a12df5 100644
--- a/fsm/nodes.go
+++ b/fsm/nodes.go
@@ -34,7 +34,11 @@ var NoteFound = Node{
 		"CopyPost": &Transition{
 			Node: &CopyPost,
 			Action: func(ctx context.Context) error {
-				l = l.Named("NoteFound")
+				//TODO: Here's the place to do validation
+				// I had an idea about parsing frontmatter into go structs,
+				// and then writing them out to a NullWriter via protobuf encoding.
+				// this would do schema checking which is nice
+				l := l.Named("NoteFound")
 				note := ctx.Value("note").(string)
 				l.Info("creating post from note", zap.String("filename", note))
 				// scan for attachments here