Derive blog post pubdate from git instead of metadata

Makefile

@@ -1,23 +1,26 @@
 .PHONY: *
 
-build:
-	./build.py out/ --draft
+help: ## display this help
+	@awk 'BEGIN{FS = ":.*##"; printf "\033[1m\nUsage\n \033[1;92m make\033[0;36m <target>\033[0m\n"} /^[a-zA-Z0-9_-]+:.*?##/ { printf "  \033[36m%-15s\033[0m %s\n", $$1, $$2 } ' $(MAKEFILE_LIST)
+
+build: ## compile src/ into out/ with pagefind
+	./build.py out/
 	pagefind --site out/
 
-clean:
+clean: ## delete out/ and src/
 	test -e out && rm -rf out || true
 	test -e srv && rm -rf srv || true
 
-watch:
+watch: ## rebuild on changes
 	while inotifywait -r -e modify -e move -e create -e delete build.py Makefile src/; do make build; done
 
-serve:
+serve: ## serve out/
 	python -m http.server --directory out/
 
-pubdate:
+pubdate: ## Replace "pubdate: now" with the current date
 	sed -i "s/pubdate: now/pubdate: $$(date -Isec)/" src/blog/**/*.md
 
-upload:
+upload: ## build to srv/ and upload to www.alogoulogoi.com
 	test -e srv && rm -rf srv || true
 	./build.py srv/
 	pagefind --site srv/

build.py

@@ -6,16 +6,26 @@ import copy
 import os
 import pathlib
 import shutil
+import subprocess
 
 import bs4
 from feedgen.feed import FeedGenerator
 import markdown
 
 
+def get_pubdate(src_path):
+    pubdate = subprocess.run(
+        ["git", "log", "--diff-filter=A", "--format=%aI", "--", src_path],
+        capture_output=True,
+        text=True,
+        check=True,
+    )
+    return datetime.fromisoformat(pubdate.stdout.strip())
+
+
 def main():
     parser = argparse.ArgumentParser()
     parser.add_argument("out", help="output directory")
-    parser.add_argument("--draft", action="store_true", help="include draft pages")
     args = parser.parse_args()
 
     src = pathlib.Path("src")
@@ -124,11 +134,8 @@ def main():
                         page.header.append(aside)
 
                 # RSS metadata
-                if "pubdate" in meta and meta["pubdate"][0] == "draft" and not args.draft:
-                    continue
-
-                if "feed" in meta and "pubdate" in meta and meta["pubdate"][0] != "draft":
-                    pubdate = datetime.fromisoformat(meta["pubdate"][0])
+                if "feed" in meta:
+                    pubdate = get_pubdate(path.as_posix())
                     link = f"https://www.alogoulogoi.com/{dest.relative_to(out).as_posix()}"
                     for feed in meta["feed"]:
                         if feed not in feeds:

flake.nix

@@ -23,12 +23,7 @@
           pkgs.pagefind
         ];
         shellHook = ''
-          echo "make build - compile src/ into out/ with pagefind"
-          echo "make clean - delete out/ and srv/"
-          echo "make watch - rebuild on changes"
-          echo "make serve - serve out/"
-          echo "make pubdate - replace 'now' with the current date"
-          echo "make upload - build to srv/ and upload to alogoulogoi"
+          make help
         '';
       };
     };

src/blog/2023/blog-start.md

@@ -1,6 +1,5 @@
 ---
 title: The traditional first software engineer blog post
-pubdate: 2023-09-28T15:39:59-07:00
 feed: blog
 ---
 

src/blog/2023/shlvl.md

@@ -1,6 +1,5 @@
 ---
 title: SHLVL PS1
-pubdate: 2023-12-18T09:53:17-08:00
 feed: blog
 ---
 

src/blog/2023/zfs-nas-backup.md

@@ -1,6 +1,5 @@
 ---
 title: Backing up my ZFS NAS to an external drive
-pubdate: 2023-09-29T16:23:49-07:00
 feed: blog
 ---
 

src/blog/2024/bookmarks.md

@@ -1,6 +1,5 @@
 ---
 title: Archiving bookmarks
-pubdate: 2024-05-27T21:06:37-07:00
 feed: blog
 ---