mox!

rfc/errata.go

@@ -0,0 +1,59 @@
+//go:build errata
+
+package main
+
+// Convert eid html file, e.g. https://www.rfc-editor.org/errata/eid3192 to text with leading blank line for references.
+// See Makefile, run with "go run errata.go < eid.html >eid.txt"
+// I could not find a source for the text version of errata.
+
+import (
+	"bufio"
+	"fmt"
+	"log"
+	"os"
+
+	"golang.org/x/net/html"
+)
+
+func xcheckf(err error, format string, args ...any) {
+	if err != nil {
+		log.Fatalf("%s: %s", fmt.Sprintf(format, args...), err)
+	}
+}
+
+func main() {
+	log.SetFlags(0)
+	doc, err := html.Parse(os.Stdin)
+	xcheckf(err, "parsing html")
+	out := bufio.NewWriter(os.Stdout)
+	_, err = out.WriteString("\n") // First line for references.
+	xcheckf(err, "write")
+
+	// We will visit the html nodes. We skip <form>'s. We turn on text
+	// output when we encounter an h3, and we stop again when we see a div
+	// or form. This works at the moment, but may break in the future.
+	output := false
+	var walk func(*html.Node)
+	walk = func(n *html.Node) {
+		if n.Type == html.ElementNode {
+			if n.Data == "form" {
+				return
+			}
+			if !output && n.Data == "h3" {
+				output = true
+			} else if output && (n.Data == "div" || n.Data == "form") {
+				output = false
+			}
+		}
+		if output && n.Type == html.TextNode {
+			_, err := out.WriteString(n.Data)
+			xcheckf(err, "write")
+		}
+		for c := n.FirstChild; c != nil; c = c.NextSibling {
+			walk(c)
+		}
+	}
+	walk(doc)
+	err = out.Flush()
+	xcheckf(err, "flush")
+}