From ca58aac41387e562c4fcf93ac6663b6735b0bcf4 Mon Sep 17 00:00:00 2001
From: Ben Kurtovic <ben.kurtovic@gmail.com>
Date: Sat, 16 Feb 2019 13:11:03 -0500
Subject: [PATCH] Add sqlite3 backend to replace mysql

---
 README.md           |  1 +
 copyvios/checker.py | 10 ++++------
 copyvios/misc.py    | 32 +++++++++++++++++++++++++++-----
 3 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/README.md b/README.md
index f4dd625..010cd72 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,7 @@ Dependencies
 * [oursql](http://packages.python.org/oursql/) >= 0.9.3.1
 * [requests](http://python-requests.org/) >= 2.9.1
 * [SQLAlchemy](http://sqlalchemy.org/) >= 0.9.6
+* [apsw](https://github.com/rogerbinns/apsw) >= 3.26.0
 * [uglifycss](https://github.com/fmarcia/UglifyCSS/)
 * [uglifyjs](https://github.com/mishoo/UglifyJS/) >= 1.3.3
 
diff --git a/copyvios/checker.py b/copyvios/checker.py
index 962a37a..ad66d21 100644
--- a/copyvios/checker.py
+++ b/copyvios/checker.py
@@ -9,7 +9,7 @@ from earwigbot.wiki.copyvios.markov import EMPTY, MarkovChain
 from earwigbot.wiki.copyvios.parsers import ArticleTextParser
 from earwigbot.wiki.copyvios.result import CopyvioSource, CopyvioCheckResult
 
-from .misc import Query, get_db
+from .misc import Query, get_db, get_cursor
 from .sites import get_site
 from .turnitin import search_turnitin
 
@@ -119,7 +119,7 @@ def _get_page_by_revid(site, revid):
         page_data["revisions"][0]["*"]  # Only need to check that these exist
         page_data["revisions"][0]["timestamp"]
     except KeyError:
-        return
+        return None
     page = site.get_page(title)
 
     # EarwigBot doesn't understand old revisions of pages, so we use a somewhat
@@ -140,7 +140,7 @@ def _get_cached_results(page, conn, mode, noskip):
                 WHERE cdata_cache_id = ?"""
     cache_id = buffer(sha256(mode + page.get().encode("utf8")).digest())
 
-    with conn.cursor() as cursor:
+    with get_cursor(conn) as cursor:
         cursor.execute(query1)
         cursor.execute(query2, (cache_id,))
         results = cursor.fetchall()
@@ -202,10 +202,8 @@ def _cache_result(page, result, conn, mode):
     data = [(cache_id, source.url[:1024], source.confidence, source.skipped,
              source.excluded)
             for source in result.sources]
-    with conn.cursor() as cursor:
-        cursor.execute("START TRANSACTION")
+    with get_cursor(conn) as cursor:
         cursor.execute(query1, (cache_id,))
         cursor.execute(query2, (cache_id, result.queries, result.time,
                                 result.possible_miss))
         cursor.executemany(query3, data)
-        cursor.execute("COMMIT")
diff --git a/copyvios/misc.py b/copyvios/misc.py
index 9c4d824..36c9ce1 100644
--- a/copyvios/misc.py
+++ b/copyvios/misc.py
@@ -1,7 +1,8 @@
 # -*- coding: utf-8  -*-
 
+from contextlib import contextmanager
 import datetime
-from os.path import expanduser
+from os.path import expanduser, join
 
 from flask import g, request
 import oursql
@@ -41,15 +42,36 @@ class _AppCache(object):
 
 cache = _AppCache()
 
-def get_db():
-    if not g._db:
-        args = cache.bot.config.wiki["_copyviosSQL"]
+def _connect_to_db(engine, args):
+    if engine == "mysql":
         args["read_default_file"] = expanduser("~/.my.cnf")
         args["autoping"] = True
         args["autoreconnect"] = True
-        g._db = oursql.connect(**args)
+        return oursql.connect(**args)
+    if engine == "sqlite":
+        import apsw
+        dbpath = join(cache.bot.config.root_dir, "copyvios.db")
+        return apsw.Connection(dbpath)
+    raise ValueError("Unknown engine: %s" % engine)
+
+def get_db():
+    if not g._db:
+        args = cache.bot.config.wiki["_copyviosSQL"].copy()
+        g._engine = engine = args.pop("engine", "mysql").lower()
+        g._db = _connect_to_db(engine, args)
     return g._db
 
+@contextmanager
+def get_cursor(conn):
+    if g._engine == "mysql":
+        with conn.cursor() as cursor:
+            yield cursor
+    elif g._engine == "sqlite":
+        with conn:
+            yield conn.cursor()
+    else:
+        raise ValueError("Unknown engine: %s" % g._engine)
+
 def get_notice():
     try:
         with open(expanduser("~/copyvios_notice.html")) as fp: