sort new to old

ref #163

.github/workflows/validate.yml

@@ -18,4 +18,4 @@ jobs:
           go-version: "1.21"
 
       - name: Run validator
-        run: make validate
+        run: make -C gobooks validate

CONTRIBUTING.md

@@ -7,12 +7,13 @@ Add books with this format :
 ```
 ### DATE - [BOOK NAME](BOOK URL)
 
-<img src="BOOK COVER IMAGE ADDRESS" width="120px"/>
+<img src="gobooks/covers/COVER_FILENAME" width="120px"/>
 
 BOOK DESCRIPTION
 
 ```
 
+* Place cover images in `gobooks/covers/` with a slug filename (e.g. `book-name.jpg`).
 * If book is free, add it after free books of that category and also add `*Free*` after book url.
 * Add other books in ascending date order (newest last). Books without date go at the end of the list in that category.
 * To keep track of the huge table of contents you can use a plugin like [Markdown VSCode plugin](https://marketplace.visualstudio.com/items?itemName=yzhang.markdown-all-in-one)

Makefile

@@ -1,3 +0,0 @@
-.PHONY: validate
-validate:
-	cd validator && go run . ../README.md

gobooks/Makefile

@@ -0,0 +1,3 @@
+.PHONY: validate
+validate:
+	cd validator && go run . ../../README.md

gobooks/validator/main.go

@@ -4,7 +4,7 @@
 // book metadata (*Last published*, *Authors*), cover images exist, covers linked.
 //
 // Usage: go run . [path/to/README.md]
-//        go run .              # uses README.md in parent dir (../README.md)
+//        go run .              # uses README.md at repo root (../../README.md)
 package main
 
 import (
@@ -16,7 +16,7 @@ import (
 )
 
 func main() {
-	readmePath := filepath.Join("..", "README.md")
+	readmePath := filepath.Join("..", "..", "README.md")
 	if len(os.Args) > 1 {
 		readmePath = os.Args[1]
 	}
@@ -236,14 +236,14 @@ func extractBookBlocks(lines []string) map[string]string {
 
 func extractCoverRefs(lines []string) []string {
 	var refs []string
-	r := regexp.MustCompile(`src="(covers/[^"]+)"`)
+	r := regexp.MustCompile(`src="(gobooks/covers/[^"]+)"`)
 	for _, line := range lines {
 		if match := r.FindStringSubmatch(line); match != nil {
 			refs = append(refs, match[1])
 		}
 	}
-	// Also check cover/ path
-	r2 := regexp.MustCompile(`src="(cover/[^"]+)"`)
+	// Also check gobooks/cover/ path (typo)
+	r2 := regexp.MustCompile(`src="(gobooks/cover/[^"]+)"`)
 	for _, line := range lines {
 		if match := r2.FindStringSubmatch(line); match != nil {
 			refs = append(refs, match[1])
@@ -254,7 +254,7 @@ func extractCoverRefs(lines []string) []string {
 
 func findUnlinkedCovers(lines []string) []string {
 	var unlinked []string
-	r := regexp.MustCompile(`<img\s+src="(covers/[^"]+)"`)
+	r := regexp.MustCompile(`<img\s+src="(gobooks/covers/[^"]+)"`)
 	for _, line := range lines {
 		// Skip if img is inside <a href> or markdown link [<img...>](url)
 		if (strings.Contains(line, "<a href=") || strings.Contains(line, "](http")) && strings.Contains(line, "<img") {