From eb89b7669d66fd7c4cdf8434a1db1bb92fca1a3a Mon Sep 17 00:00:00 2001
From: Howon Lee <hlee.howon@gmail.com>
Date: Tue, 8 Jun 2021 10:38:00 -0700
Subject: [PATCH] Detect if file is blank or bad for SQLite DB connection
(#16372)
Previously just used JDBC. However, JDBC will merrily execute queries on empty file locations for SQLite, because it'll create a new SQLite file. This one checks that there exists a SQLite file already to be querying in the first place
---
.../sqlite/src/metabase/driver/sqlite.clj | 20 ++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/modules/drivers/sqlite/src/metabase/driver/sqlite.clj b/modules/drivers/sqlite/src/metabase/driver/sqlite.clj
index ec76491fb70..88d23de96ed 100644
--- a/modules/drivers/sqlite/src/metabase/driver/sqlite.clj
+++ b/modules/drivers/sqlite/src/metabase/driver/sqlite.clj
@@ -1,5 +1,6 @@
(ns metabase.driver.sqlite
- (:require [clojure.string :as str]
+ (:require [clojure.java.io :as io]
+ [clojure.string :as str]
[honeysql.core :as hsql]
[honeysql.format :as hformat]
[java-time :as t]
@@ -38,6 +39,23 @@
;; for now we'll just skip the foreign key stuff in the tests.
(defmethod driver/supports? [:sqlite :foreign-keys] [_ _] (not config/is-test?))
+;; Every SQLite3 file starts with "SQLite Format 3"
+;; or "** This file contains an SQLite
+;; There is also SQLite2 but last 2 version was 2005
+(defn- confirm-file-is-sqlite [filename]
+ (with-open [reader (io/input-stream filename)]
+ (let [outarr (byte-array 50)]
+ (.read reader outarr)
+ (let [line (String. outarr)]
+ (or (str/includes? line "SQLite format 3")
+ (str/includes? line "This file contains an SQLite"))))))
+
+(defmethod driver/can-connect? :sqlite
+ [driver details]
+ (if (confirm-file-is-sqlite (:db details))
+ (sql-jdbc.conn/can-connect? driver details)
+ false ))
+
(defmethod driver/db-start-of-week :sqlite
[_]
:sunday)
--
GitLab