feat: add timestamp to post follow [ UNICT-DMI#136 ]

.github/CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   - The python package name will be `telegram-spotted-dmi-bot` (hence `pip install telegram-spotted-dmi-bot`)
   - The name of the main module will be `spotted` (hence `import spotted`)
 - the project will be versioned, starting from 2.0.0. So you will need a tag with a new version to publish the new python package
+- Timestamp to the user_follow table to keep track of when a user started following a post
 
 ### Fixed
 

src/spotted/config/db/post_db_init.sql

@@ -64,5 +64,7 @@ CREATE TABLE IF NOT EXISTS user_follow
 (
   user_id BIGINT NOT NULL,
   message_id BIGINT NOT NULL,
-  private_message_id BIGINT NOT NULL
-);
+  private_message_id BIGINT NOT NULL,
+  follow_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+  PRIMARY KEY (user_id, message_id)
+);

src/spotted/data/user.py

@@ -18,11 +18,13 @@ class User:
         user_id: id of the user
         private_message_id: id of the private message sent by the user to the bot. Only used for following
         ban_date: datetime of when the user was banned. Only used for banned users
+        follow_date: datetime of when the user started following a post. Only used for following users
     """
 
     user_id: int
     private_message_id: int | None = None
     ban_date: datetime | None = None
+    follow_date: datetime | None = None
 
     @property
     def is_pending(self) -> bool:
@@ -67,10 +69,10 @@ def following_users(cls, message_id: int) -> "list[User]":
             in the user's conversation with the bot
         """
         return [
-            cls(user_id=row["user_id"], private_message_id=row["private_message_id"])
+            cls(user_id=row["user_id"], private_message_id=row["private_message_id"], follow_date=row["follow_date"])
             for row in DbManager.select_from(
                 table_name="user_follow",
-                select="user_id, private_message_id",
+                select="user_id, private_message_id, follow_date",
                 where="message_id = %s",
                 where_args=(message_id,),
             )