From d2733ccf017cd37b60792a1ae8586e8eaa375992 Mon Sep 17 00:00:00 2001
From: Greg Burri <greg.burri@gmail.com>
Date: Tue, 6 May 2025 16:24:45 +0200
Subject: [PATCH] Add some CHECK constraints for data validation.

---
 backend/sql/version_1.sql | 85 ++++++++++++++++++++++-----------------
 1 file changed, 48 insertions(+), 37 deletions(-)

diff --git a/backend/sql/version_1.sql b/backend/sql/version_1.sql
index 61d72a5..0e44445 100644
--- a/backend/sql/version_1.sql
+++ b/backend/sql/version_1.sql
@@ -30,23 +30,19 @@ CREATE TABLE [User] (
     -- Password can only be reset during a certain duration after this time.
     [password_reset_datetime] TEXT,
 
-    [is_admin] INTEGER NOT NULL DEFAULT FALSE
+    [is_admin] INTEGER NOT NULL DEFAULT FALSE,
+
+    CHECK (
+        length([email]) <= 255 AND
+        length([name]) <= 255 AND
+        length([password]) <= 255 AND
+        [first_day_of_the_week] >= 0 AND [first_day_of_the_week] <= 6
+    )
 ) STRICT;
 
 CREATE INDEX [validation_token_index] ON [User]([validation_token]);
 CREATE UNIQUE INDEX [User_email_index] ON [User]([email]);
 
-CREATE TRIGGER [User_trigger_update_first_day_of_the_week]
-BEFORE UPDATE OF [first_day_of_the_week]
-ON [User]
-BEGIN
-    SELECT
-        CASE
-            WHEN NEW.[first_day_of_the_week] < 0 OR NEW.[first_day_of_the_week] > 6 THEN
-                RAISE (ABORT, 'Invalid [first_day_of_the_week] value')
-        END;
-END;
-
 CREATE TABLE [UserLoginToken] (
     [id] INTEGER PRIMARY KEY,
     [user_id] INTEGER NOT NULL,
@@ -56,9 +52,14 @@ CREATE TABLE [UserLoginToken] (
     -- Can be stored in a cookie to be able to authenticate without a password.
     [token] TEXT NOT NULL,
 
-    [ip] TEXT, -- Can be ipv4 or ipv6
+    [ip] TEXT, -- Can be ipv4 or ipv6.
     [user_agent] TEXT,
 
+    CHECK (
+        length([ip]) <= 255 AND
+        length([user_agent]) <= 255
+    ),
+
     FOREIGN KEY([user_id]) REFERENCES [User]([id]) ON DELETE CASCADE
 ) STRICT;
 
@@ -78,31 +79,15 @@ CREATE TABLE [Recipe] (
     [is_public] INTEGER NOT NULL DEFAULT FALSE,
     [creation_datetime] TEXT NOT NULL,
 
+    CHECK (
+        length([title]) <= 255 AND
+        length([description]) <= 65535 AND
+        [difficulty] >= 0 AND [difficulty] <= 3
+    ),
+
     FOREIGN KEY([user_id]) REFERENCES [User]([id]) ON DELETE SET NULL
 ) STRICT;
 
-CREATE TRIGGER [Recipe_trigger_update_difficulty]
-BEFORE UPDATE OF [difficulty]
-ON [Recipe]
-BEGIN
-    SELECT
-        CASE
-            WHEN NEW.[difficulty] < 0 OR NEW.[difficulty] > 3 THEN
-                RAISE (ABORT, 'Invalid [difficulty] value')
-        END;
-END;
-
-CREATE TRIGGER [Recipe_trigger_insert_difficulty]
-BEFORE INSERT
-ON [Recipe]
-BEGIN
-    SELECT
-        CASE
-            WHEN NEW.[difficulty] < 0 OR NEW.[difficulty] > 3 THEN
-                RAISE (ABORT, 'Invalid [difficulty] value')
-        END;
-END;
-
 CREATE TABLE [Image] (
     [Id] INTEGER PRIMARY KEY,
     [recipe_id] INTEGER NOT NULL,
@@ -110,6 +95,11 @@ CREATE TABLE [Image] (
     [description] TEXT NOT NULL DEFAULT '',
     [image] BLOB NOT NULL,
 
+    CHECK (
+        length([name]) <= 255 AND
+        length([description]) <= 255
+    ),
+
     FOREIGN KEY([recipe_id]) REFERENCES [Recipe]([id]) ON DELETE CASCADE
 ) STRICT;
 
@@ -127,8 +117,11 @@ CREATE TABLE [RecipeTag] (
 
 CREATE TABLE [Tag] (
     [id] INTEGER PRIMARY KEY,
-    [name] TEXT NOT NULL
-     -- https://en.wikipedia.org/wiki/List_of_ISO_639_language_codes
+    [name] TEXT NOT NULL,
+
+    CHECK (
+        length([name]) <= 31
+    )
 ) STRICT;
 
 CREATE UNIQUE INDEX [Tag_name_lang_index] ON [Tag]([name]);
@@ -142,6 +135,11 @@ CREATE TABLE [Group] (
     [name] TEXT NOT NULL DEFAULT '',
     [comment] TEXT NOT NULL DEFAULT '',
 
+    CHECK (
+        length([name]) <= 255 AND
+        length([comment]) <= 65535
+    ),
+
     FOREIGN KEY([recipe_id]) REFERENCES [Recipe]([id]) ON DELETE CASCADE
 ) STRICT;
 
@@ -155,6 +153,10 @@ CREATE TABLE [Step] (
 
     [action] TEXT NOT NULL DEFAULT '',
 
+    CHECK (
+        length([action]) <= 255
+    ),
+
     FOREIGN KEY(group_id) REFERENCES [Group](id) ON DELETE CASCADE
 ) STRICT;
 
@@ -172,6 +174,11 @@ CREATE TABLE [Ingredient] (
 
     [comment] TEXT NOT NULL DEFAULT '',
 
+    CHECK (
+        length([name]) <= 255 AND
+        length([comment]) <= 65535
+    ),
+
     FOREIGN KEY([step_id]) REFERENCES [Step]([id]) ON DELETE CASCADE
 ) STRICT;
 
@@ -210,6 +217,10 @@ CREATE TABLE [ShoppingEntry] (
     [quantity_unit] TEXT NOT NULL DEFAULT '',
     [servings] INTEGER,
 
+    CHECK (
+        length([name]) <= 255
+    ),
+
     FOREIGN KEY([user_id]) REFERENCES [User]([id]) ON DELETE CASCADE,
     FOREIGN KEY([ingredient_id]) REFERENCES [Ingredient]([id]) ON DELETE SET NULL,
     FOREIGN KEY([recipe_scheduled_id]) REFERENCES [RecipeScheduled]([id]) ON DELETE SET NULL