Initial import

cache.py

@@ -0,0 +1,86 @@
+from hashlib import sha1
+import logging
+import sqlite3
+
+try:
+    SQLITE_PATH = getattr(settings, SQLITE_DB_PATH, 'cache.sqlite3')
+except:
+    SQLITE_PATH = 'cache.sqlite3'
+
+class DbCacheHandler:
+    """
+    Database backed cache handler for Entity's eveapi module
+    """
+
+    def __init__(self, conn=SQLITE_PATH):
+        self._conn_url = conn
+
+    @property
+    def log(self):
+        if not hasattr(self, '_log'):
+            self._log = logging.getLogger(self.__class__.__name__)
+        return self._log
+
+    @property
+    def conn(self):
+        if not hasattr(self, '_conn') or not self._conn:
+            self._conn = sqlite3.connect(self._conn_url)
+            self.setup()
+        return self._conn
+
+    @property
+    def cursor(self):
+        if not hasattr(self, '_cursor') or not self._cursor:
+            self._cursor = self.conn.cursor()
+        return self._cursor
+
+    def setup(self):
+        if not hasattr(self, '_setupchecked'):
+            self.cursor.execute('CREATE TABLE IF NOT EXISTS api_cache(docid TEXT PRIMARY KEY, xml TEXT, cacheduntil TEXT)')
+            self._setupchecked = True
+
+    def disconnect(self):
+        if hasattr(self, '_cursor'):
+            self._cursor.close()
+            self._cursor = None
+        if hasattr(self, '_conn'):
+            self._conn.close()
+            self._conn = None
+
+    @staticmethod
+    def _gen_docid(host, path, params):
+        return sha1("%s%s?%s" % (host, path, params)).hexdigest()
+
+    def retrieve(self, host, path, params):
+        docid = self._gen_docid(host, path, params)
+        self.log.debug("Retrieving document: %s" % docid)
+        try:
+            self.cursor.execute("SELECT xml FROM api_cache WHERE docid = ? and datetime(cacheduntil, 'unixepoch') >= current_timestamp", (docid,))
+            res = self.cursor.fetchone()
+            self.disconnect()
+        except sqlite3.Error as e:
+            self.log.error("Error retrieving document: %s", e.args[0])
+        else:
+            if res:
+                self.log.debug("Found %s documents for ID %s" % (len(res), docid))
+                return res[0]
+        return None
+
+    def store(self, host, path, params, doc, obj):
+        docid = self._gen_docid(host, path, params)
+        self.log.debug("Storing document: %s (%s)" % (docid, path))
+        try:
+            self.cursor.execute('REPLACE INTO api_cache (docid, xml, cacheduntil) VALUES (?, ?, ?)', (docid, doc, obj.cachedUntil))
+            self.conn.commit()
+            self.disconnect()
+        except sqlite3.Error as e:
+            self.log.error("Error storing document: %s", e.args[0])
+
+    def purge_stale(self):
+        self.log.info("Purging stale cached documents")
+        try:
+            self.cursor.execute("DELETE FROM api_cache WHERE datetime(cacheduntil, 'unixepoch') >= current_timestamp")
+            self.conn.commit()
+            self.disconnect()
+        except sqlite3.Error as e:
+            self.log.error("Error purging document cache: %s", e.args[0])