session: load/create wrapper methods for SessionDB

mitmproxy/addons/session.py

@@ -0,0 +1,59 @@
+import os
+import sqlite3
+
+from mitmproxy.exceptions import SessionLoadException
+from mitmproxy.utils.data import pkg_data
+
+
+# Could be implemented using async libraries
+class SessionDB:
+    """
+    This class wraps connection to DB
+    for Sessions and handles creation,
+    retrieving and insertion in tables.
+    """
+
+    def __init__(self, db_path=None):
+        """
+        Connect to an already existing database,
+        or create a new one with optional path.
+        :param db_path:
+        """
+        if db_path is not None and os.path.isfile(db_path):
+            self._load_session(db_path)
+        else:
+            path = db_path or 'tmp.sqlite'
+            # in case tmp.sqlite already exists in FS
+            if os.path.isfile(path):
+                os.remove(path)
+            self.con = sqlite3.connect(path)
+            script_path = pkg_data.path("io/sql/session_create.sql")
+            qry = open(script_path, 'r').read()
+            with self.con:
+                self.con.executescript(qry)
+
+    def _load_session(self, path):
+        if not self.is_session_db(path):
+            raise SessionLoadException('Given path does not point to a valid Session')
+        self.con = sqlite3.connect(path)
+
+    @staticmethod
+    def is_session_db(path):
+        """
+        Check if database entered from user
+        is a valid Session SQLite DB.
+        :return: True if valid, False if invalid.
+        """
+        try:
+            c = sqlite3.connect(f'file:{path}?mode=rw', uri=True)
+            cursor = c.cursor()
+            cursor.execute("SELECT NAME FROM sqlite_master WHERE type='table';")
+            rows = cursor.fetchall()
+            tables = [('FLOW',), ('BODY',), ('META',), ('ANNOTATION',)]
+            if all(elem in rows for elem in tables):
+                c.close()
+                return True
+        except:
+            if c:
+                c.close()
+        return False