block: try to unify the mirror block modules

app/terraform/block_mirror.py

@@ -0,0 +1,79 @@
+from datetime import datetime, timedelta
+import logging
+from abc import abstractmethod
+from fnmatch import fnmatch
+from typing import Tuple, List
+
+from app.extensions import db
+from app.models.activity import Activity
+from app.models.mirrors import Proxy
+from app.terraform import BaseAutomation
+
+
+class BlockMirrorAutomation(BaseAutomation):
+
+    patterns: List[str]
+
+    def __init__(self):
+        """
+        Constructor method.
+        """
+        self.patterns = list()
+        super().__init__()
+
+    def automate(self, full: bool = False) -> Tuple[bool, str]:
+        self.fetch()
+        self.parse()
+        rotated = list()
+        for pattern in self.patterns:
+            for proxy in active_proxies():
+                if proxy.url is None:
+                    # Not ready yet
+                    continue
+                if fnmatch(proxy.url, pattern):
+                    logging.debug("Found %s blocked", proxy.url)
+                    if not proxy.origin.auto_rotation:
+                        logging.debug("Proxy auto-rotation forbidden for origin")
+                        continue
+                    if proxy.added > datetime.utcnow() - timedelta(hours=3):
+                        logging.debug("Not rotating a proxy less than 3 hours old")
+                        continue
+                    if proxy.deprecate(reason=self.short_name):
+                        logging.info("Rotated %s", proxy.url)
+                        rotated.append((proxy.url, proxy.origin.domain_name))
+                    else:
+                        logging.debug("Not rotating a proxy that is already deprecated")
+        if rotated:
+            activity = Activity(
+                activity_type="block",
+                text=(f"[{self.short_name}] ♻ Rotated {len(rotated)} proxies️️: \n" +
+                      "\n".join([f"* {proxy_domain} ({origin_domain})" for proxy_domain, origin_domain in rotated]))
+            )
+            db.session.add(activity)
+            db.session.commit()
+            activity.notify()
+        return True, ""
+
+    @abstractmethod
+    def fetch(self):
+        """
+        Fetch the blocklist data. It is the responsibility of the automation task
+        to persist this within the object for the parse step.
+
+        :return: None
+        """
+
+    @abstractmethod
+    def parse(self):
+        """
+        Parse the blocklist data.
+
+        :return: None
+        """
+
+
+def active_proxies() -> List[Proxy]:
+    return Proxy.query.filter(
+        Proxy.deprecated.is_(None),
+        Proxy.destroyed.is_(None)
+    ).all()