simplify the user authentication example and make it easier to adapt to different databases

Author: lovasoa

CHANGELOG.md

@@ -8,7 +8,7 @@
    - The *submit* button can now be customized, and can be removed completely, which is useful to create multiple submit buttons that submit the form to different targets.
  - Support non-string values in markdown fields. `NULL` values are now displayed as empty strings, numeric values are displayed as strings, booleans as `true` or `false`, and arrays as lines of text. This avoids the need to cast values to strings in SQL queries.
  - Revert a change introduced in v0.15.0:
-    - Re-add the systematic `CAST(? AS TEXT)` around variables, which helps the database know which type it is dealing with in advance. This fixes a regression in 0.15 where some SQLite websites were broken because of missing affinity information. In SQLite `SELECT '1' = 1` returns `false` but `SELECT CAST('1' AS TEXT) = 1` returns `true`.
+    - Re-add the systematic `CAST(? AS TEXT)` around variables, which helps the database know which type it is dealing with in advance. This fixes a regression in 0.15 where some SQLite websites were broken because of missing affinity information. In SQLite `SELECT '1' = 1` returns `false` but `SELECT CAST('1' AS TEXT) = 1` returns `true`. This also fixes error messages like `could not determine data type of parameter $1` in PostgreSQL.
  - Fix a bug where [cookie](https://sql.ophir.dev/documentation.sql?component=cookie#component) removal set the cookie value to the empty string instead of removing the cookie completely.
  - Support form submission using the [button](https://sql.ophir.dev/documentation.sql?component=button#component) component using its new `form` property. This allows you to create a form with multiple submit buttons that submit the form to different targets.
 

examples/user-authentication/create_user.sql

@@ -1,21 +1,10 @@
-WITH inserted_user AS (
-    INSERT INTO user_info (username, password_hash)
-    VALUES (:username, sqlpage.hash_password(:password))
-    ON CONFLICT (username) DO NOTHING
-    RETURNING username
-)
-SELECT 'hero' AS component,
-    'Welcome' AS title,
-    'Welcome, ' || username || '! Your user account was successfully created. You can now log in.' AS description,
-    'https://upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Community_wp20.png/974px-Community_wp20.png' AS image,
-    'signin.sql' AS link,
-    'Log in' AS link_text
-FROM inserted_user
-UNION ALL
-SELECT 'hero' AS component,
-    'Sorry' AS title,
-    'Sorry, this user name is already taken.' AS description_md,
-    'https://upload.wikimedia.org/wikipedia/commons/thumb/f/f0/Sad_face_of_a_Wayuu_Woman.jpg/640px-Sad_face_of_a_Wayuu_Woman.jpg' AS image,
-    'signup.sql' AS link,
-    'Try again' AS link_text
-WHERE NOT EXISTS (SELECT 1 FROM inserted_user);
+INSERT INTO user_info (username, password_hash)
+VALUES (:username, sqlpage.hash_password(:password))
+ON CONFLICT (username) DO NOTHING
+RETURNING 
+    'redirect' AS component,
+    'create_user_welcome_message.sql?username=' || :username AS link;
+
+-- If we are still here, it means that the user was not created
+-- because the username was already taken.
+SELECT 'redirect' AS component, 'create_user_welcome_message.sql?error&username=' || :username AS link;

examples/user-authentication/create_user_welcome_message.sql

@@ -0,0 +1,15 @@
+SELECT 'hero' AS component,
+    'Welcome' AS title,
+    'Welcome, ' || $username || '! Your user account was successfully created. You can now log in.' AS description,
+    'https://upload.wikimedia.org/wikipedia/commons/thumb/e/e1/Community_wp20.png/974px-Community_wp20.png' AS image,
+    'signin.sql' AS link,
+    'Log in' AS link_text
+WHERE $error IS NULL;
+
+SELECT 'hero' AS component,
+    'Sorry' AS title,
+    'Sorry, the user name "' || $username || '" is already taken.' AS description,
+    'https://upload.wikimedia.org/wikipedia/commons/thumb/f/f0/Sad_face_of_a_Wayuu_Woman.jpg/640px-Sad_face_of_a_Wayuu_Woman.jpg' AS image,
+    'signup.sql' AS link,
+    'Try again' AS link_text
+WHERE $error IS NOT NULL;

examples/user-authentication/docker-compose.yml

@@ -1,10 +1,11 @@
 services:
   web:
-    image: lovasoa/sqlpage
+    image: lovasoa/sqlpage:main # main is cutting edge, use lovasoa/sqlpage:latest for the latest stable version
     ports:
       - "8080:8080"
     volumes:
       - .:/var/www
+      - ./sqlpage:/etc/sqlpage
     depends_on:
       - db
     environment: