Add decorators to display "unavailable" message when scraping is runn…

…ing.

paperoni/webapp/common.py

@@ -14,6 +14,7 @@
 
 from ..cli_helper import search
 from ..utils import keyword_decorator
+from .utils import redirect_index_if_scraping, redirect_page_if_scraping
 from . import filters
 
 here = Path(__file__).parent
@@ -620,11 +621,6 @@ def template(path, location=None, **kw):
     )
 
 
-def scraper_is_running():
-    status = os.popen("systemctl is-active paperoni-scraper.service").read().strip()
-    return status
-
-
 # TODO: This is a copy of grizzlaxy.index.Index to avoid updating grizzlaxy during
 # my time off -- OB
 class Index(LoneBear):
@@ -635,13 +631,11 @@ def __init__(self, template=here / "mila-template.html"):
         self.location = template.parent if isinstance(template, Path) else None
         self.template = template
 
+    @redirect_index_if_scraping
     async def run(self, request):
         scope = request.scope
         app = scope["app"]
         root_path = scope["root_path"]
-
-        print("GOTO", repr(root_path), scraper_is_running())
-
         content = render("/", app.map, restrict=root_path)
         if content is None:
             content = render(
@@ -675,4 +669,4 @@ async def app(page):
         page.print(target := H.div().autoid())
         return await fn(page, page[target])
 
-    return bear(app, template_params={"title": actual_title})
+    return bear(redirect_page_if_scraping(app), template_params={"title": actual_title})

paperoni/webapp/help.py

@@ -5,11 +5,13 @@
 from starbear import simplebear, template
 
 from .common import template
+from .utils import redirect_request_if_scraping
 
 here = Path(__file__).parent
 
 
 @simplebear
+@redirect_request_if_scraping
 async def help(request):
     """Help."""
     md = (here / "help.md").read_text()

paperoni/webapp/utils.py

@@ -1,6 +1,9 @@
+import os
 import logging
 import re
 from datetime import datetime
+import functools
+from hrepr import H
 
 
 # TODO: move this to starbear and starbear.utils.StarbearHandler
@@ -128,3 +131,67 @@ def paper_score(self, paper):
         ]
         total_score = sum(x for _, x in author_scores)
         return total_score, author_scores
+
+
+UNAVAILABLE_TITLE = "Server temporarily unavailable, please retry later"
+UNAVAILABLE_CONTENT = (
+    "Server is temporarily unavailable, please retry in few minutes."
+)
+
+
+def scraper_is_running() -> bool:
+    """Return True if Paperoni scraping service is running."""
+    status = (
+        os.popen("systemctl is-active paperoni-scraper.service").read().strip()
+    )
+    return status != "inactive"
+
+
+def redirect_index_if_scraping(method):
+    """Decorator to display temporarily unavailable page on Index.__call__() if scraping is running."""
+    from .common import template
+
+    @functools.wraps(method)
+    async def wrapper(self, *args, **kwargs):
+        if scraper_is_running():
+            return template(
+                self.template,
+                body=H.div(UNAVAILABLE_CONTENT, id="index"),
+                title=UNAVAILABLE_TITLE,
+            )
+        else:
+            return await method(self, *args, **kwargs)
+
+    return wrapper
+
+
+def redirect_request_if_scraping(fn):
+    """Decorator to display temporarily unavailable page on run(request) if scraping is running."""
+    from .common import template, here
+
+    @functools.wraps(fn)
+    async def wrapper(request):
+        if scraper_is_running():
+            return template(
+                here / "mila-template.html",
+                title=UNAVAILABLE_TITLE,
+                body=H.div(UNAVAILABLE_CONTENT),
+            )
+        else:
+            return await fn(request)
+
+    return wrapper
+
+
+def redirect_page_if_scraping(fn):
+    """Decorator to display temporarily unavailable page on app(page, ...) if scraping is running."""
+
+    @functools.wraps(fn)
+    async def wrapper(page, *args, **kwargs):
+        if scraper_is_running():
+            page["head"].print(H.title(UNAVAILABLE_TITLE))
+            page.print(UNAVAILABLE_CONTENT)
+        else:
+            await fn(page, *args, **kwargs)
+
+    return wrapper